My Biggest Regret Building a Net Zero Home

[@UndecidedMF]

Would you want to build new or go with a retrofit? The first 100 people to use code UNDECIDED at the link below will get 20% off of Incogni: incogni.com/undecided. If you liked this video, check out: Exploring Passive House Design - 90% Energy Savings! kzbin.info/www/bejne/qZbGc2aIZdh8j7c

[@cp37373]

But will you be going over the actual cost of these items and how much the process and consultation stuff cost?

[@michaelmayhem350]

I strongly strongly strongly urge you to make friends with some IT people especially ones with Linux and home network experience. Have them help you select "smart" home products that can be run exclusively from a closed home network. This is both for your security & to prevent you from being at another companies mercy. If Alexa controls your doors windows & AWS haS an outage, you're now locked out of your home in the rain. (AWS averages 3 to 4 outages a year) Or even worse when companies go bankrupt or simply turn off the check-in server products require to function because they want to push your towards new products or just don't pay to pay to runs the servers anymore. Well now you can't control your shades or lights until you redo your home set up completely.

[@AlecMuller]

FWIW, I'm very interested in cold-climate retrofits. Our ~1200 square foot house is 35 years old and in the same climate as you, Matt. It's not horrible in terms of insulation and draftiness, but we still burned 3 cords of wood last winter. We hope to re-side, add exterior insulation (e.g. taped 2" rigid foam), improve the air tightness, and add an ERV. There seems to be a lot more content on new construction than for retrofits (especially retrofits extending beyond the original 2x6 studs).

[@stygiansage2661]

For me I would want to build new, but that is so I can get everything I want in the layout. But for any of that I would need the funds.

[@wjm1319]

I'm building new. Plans are with architect/engineer for a self-designed multi-generational triplex built with ICF w/ a cement roof. I'm not necessarily trying for Passive certification, but I'm incorporating a lot of the practices.

[@jopo7996]

I tried designing an efficient home with my wife, but it always turned out to be a passive aggressive house.

[@MarcBaise]

Lol

[@davejack8973]

BAAHAHAHAHHA welcome to MARRIED LIFE!

[@UndecidedMF]

😂

[@williamarmstrong7199]

You are lucky.. no "passive" from my 'better half" lol the "change" was not for the better.

[@SiisKolkytEuroo]

@@UndecidedMF please fix the subtitles, they have differences to what is actually being said in the video. As in completely different word choices in many places

[@2nd-place]

A family member built one of these. When we went to visit them, they showed us the paperwork that we will be inheriting it! They have no kids or spouse. I was taken aback. It is a very nice home and they had an architect design some really nice features. I feel so lucky and blessed. My wife and I could never afford to build a home like this. This property will be amazing for us in our retirement since it’s net zero and we don’t have a lot of savings, it even has a deep well so no water bill. It’s in an absolutely beautiful scenic location as well. Moral of the story is always be nice to your relatives and maintain relationships with them. Being the nice guy finally paid off! I can at least know that we’ll be warm with a roof over our heads when we’re old! It’s like a burden was lifted.

[@tealkerberus748]

I hope this comes true for you. I'm seeing a lot of stories of older people thinking they were going to leave their beautiful home to a loved younger relative, only to have the entire value of that asset stripped away from them by exorbitant nursing home fees and end-of-life care. I'm in my forties and already planning how to make sure that doesn't happen to my legacy for my kids, but it's a bit awkward for the younger generation to raise the topic with their elders if the elders haven't mentioned it first!

[@eklectiktoni]

Timing is so tricky since we can't accurately predict the future. But I think the old adage about planting trees might apply: _The best time to plant a tree is 10 years ago, the next best time is now._ I think net zero builds are fascinating so I'm excited to see the progress of both houses.

[@lapaleves]

and the best kind of tree to plant 10 years ago is any fruit...

[@fanfeck2844]

When’s the best time to buy technology? Tomorrow

[@Tigerhearty]

net zero builds are a lie. just like solar panels environmental costs is just out of this world too

[@ZeroEnergyBuildingLLC]

Getting a passive, LEED, net-zero, or any third party certification adds cost to any project. As a business guy, I didn't understand the justification of added costs telling you that your house is efficient at first; but soon realized that it is a MUST if you want any chance of re-cooping the additional costs of anything energy efficiency in the sale of the house. Certification is the only way to transfer the additional costs into value.

[@JesseArt]

My dad built a passively solar heated home utilizing greenhouses when we lived in New Hampshire. I'm not sure it would earn those shiny certifications today, but it was incredibly well insulated and did have excellent airflow. In winter even, as long as the sun was out, we often didn't even need to light the wood stove. We could just open the sliding doors to the up and downstairs greenhouses (porch/balcony rooms) and let the hot air in. With the glass south facing and the sun low enough in the sky for both direct and indirect radiant heat, it worked great. And the roof's overhang was long enough that it provided ample shade in the summertime, so we were never overwhelmed with heat in summer either. I remember getting my parents in trouble when I was little at school because I didn't understand at the time how it all worked and I told my teacher that we didn't have any heat at home other than the wood stove we sometimes lit downstairs. Ultimately, we lost that house when I was in grade school due to bankruptcy, but I always loved the simplicity of the design and the effectiveness of it. If I could ever afford to build my own, I would absolutely build something similar with a Net Zero goal. Personally, I love the idea of partially underground builds that maintain reasonable temperatures year round.

[@alxvicmom]

Any chance you remember the address, Im curious to see what it looked like? I visited troglodytes homes in France in Middleschool and yes they stay at reasonable temperature all year round. They were pretty cool.

[@CBDguitar]

Sounds like it was a neat house to live in!

[@mirola73]

Your dad was clearly smart way before it caught on everywhere else.

[@wellsleger7916]

Hey Matt, I built an icf home and a 40k off grid solar system with batteries. Would love to talk and share a couple ideas with ya!!

[@3crowsfarm16]

Big project! We built our efficient home 10 years ago in the BC Rockies. It is strawbale timberframe with annualized geo solar heat and dhw. Summer solar heat is moved into geothermal lines, my subsoil is currently 73f making winter heating more efficient. We were able to use a lot of local and salvaged building materials. What we saved in purchases we spent on increased labour, but more of our money stayed local this way. Just installed the PV system last year and our 8kw system is covering %80 of hydro bill.

[@jamesmansion2572]

I'm jealous! Almost no timber framing available in Portugal. Concrete frame and infill or lightweight steel premade in China, which I'm not so keen on at the moment. Also its 'encouraged' to build a basement, for local planning reasons.

[@pierredentremont2999]

@The Glorious White Male straw bale houses in BC Are a thing and legal.

[@matthewprather7386]

@The Glorious White Male it pays to do your homework, as always! Check with the building inspector and check local codes before doing any work. Measure twice, cut once, as they say!

[@jordanlarson6488]

This is amazing. I would love to see a video tour and hear a more in depth discussion/presentation of your home!

[@jordanabendroth6458]

How does solar make your water bill cheaper?

[@Lew114]

Congratulations on getting your new project started. I’m excited to see it unfold. We should all keep in mind that energy efficiency isn’t all or nothing. Going full on NetZero might not be a good choice for some of us, but that doesn’t mean we can’t benefit from implementing a subset of the features of a net zero home. Adding insulation, installing a more efficient heating and cooling system, or maybe even adding few solar panels can make a big difference even if we fall well short of net zero.

[@geradkavanagh8240]

Every little bit counts. Just installing new light bulbs and flourescent lights dropped our power usage 15%.

[@mennol3885]

True, a low hanging fruits approach. Also overbuilding on solar energy to charge your electric vehicle at home might be more effective than hunting those last percents. And keep in mind that personal energy use is not the biggest polluter. All the stuff you buy has to be produced and transported. If it is expensive, it is probably not environmentally friendly.

[@Lew114]

@@mennol3885 That’s a great point about the stuff we buy. I tend to forget about that.

[@cabanis]

Not just the savings in energy cost, passive house design brings an additional level of comfort. No more cold floors or even a need for heated floors when you focus on thermal bridging.

[@UndecidedMF]

I'm really excited about that.

[@michaelfried3123]

when my floors get cold, I do something old fashioned, its called putting shoes on, they cost me $20 a year to replace, problem solved.

[@mauriceharting5877]

Net-zero residential homes are expensive due to extra design, testing and material cost requirements. But the biggest issue with net-zero homes is indoor air pollution due to the air tightness with the cleaning chemicals and detergents we use daily. HEPA filters do not remove gases only small particulate matter. The extra cost of net-zero homes (at least 10% higher overall costs) and less actual usable floor space is also a problem. Most of the heat loss in any home (net-zero or not) is through windows and doors with the best ones only giving us a R factor of 8 (triple glazed e panes) and most half that (double glazed e panes). So the cost of a residential home at a cost of $ 1,000,000 would cost at least $ 1,100.000 for net-zero and probably more with certification, etc.

[@gatgolf]

a couple of items I ran into when building an energy efficient house. in no particular order. 1. seal the juncture between the outside sheathing and the mudsill/foundation. 2. make sure the ZIP tape on the sheathing is properly rolled after application, the contractors don't like doing this. 3. insulate under and around your concrete slab, whether it is your main floor or your basement floor. 4. Seal the drywall to the walls around the the floor and headers and all outside openings. 5. Sprayfoam all basement walls and extend up into the rim joists. 6. Make sure to use all airtight can lighting and any other ceiling penetrations. 7. Seal your air ducts, we used a product/process called aero-seal. 6. Inspect frequently during construction at all phase and all times of day... you can catch and foam seal alot of small imperfections before they get covered up. I wasn't going for passive, just low utility bills and high comfort, so no self generation or storage. Did pretty good - 3900 ft^2 house and in worts of summer looking about $100 month total electric and in coldest winter months about $150. 21 SEER Daikin inverter and a Rheem heat pump water heater.

[@brandonwallace9399]

@Undecided with Matt Ferrell I have an open geothermal system installed in my home. I was going to use Water Furnace as well but found out it is the luxury brand of Geostar. Similar to Lexus and Toyota. However with Water Furnace the internal components to the units are exactly the same. I have confirmed this with multiple employees. The Water Furnace has a nicer exterior paint job/graphics but that is all you get for what you pay for between the two units. I have a Geostar unit and it has been great. Support for it has been difficult in my area so I have had to learn how to maintain and troubleshoot it. I have made some modifications to my system so it is more efficient for heating. Just thought I would let you know you can save some money by going with Geostar.

[@_Phillter]

My wife and I just finished building a factory house where we are settling in Saitama, Japan, and are moving in at the end of Oct. We went with a 10kWh solar system (because getting more meant registering as an independent power station), and just got the air-tightness results back a month ago, getting 0.5 all 3 times. We went with the company Ichijou because of their solar roofing and home battery options, as well as their really strict adherence to foreign-company levels of energy and materials efficiency. Hope your new home ends up being amazing!

[@strongbrew9116]

Is the requirement to register an an independent power station if over 10kWh to discourage people from being completely independent from the grid? Is it very difficult/costly to register?

[@_Phillter]

@@strongbrew9116 I'm not sure to be honest. In the Bureaucratic nightmare that is 99% of Japanese paperwork, as soon as we heard that we would have to jump through some other hoop, we skipped any thoughts of going that route.

[@edam9461]

@@strongbrew9116 I believe its due to differences in the Fit (feed in tariff) and tax benefits/grants received. I'm currently building similarly in Yokohama and heard that as the explanation.

[@strongbrew9116]

@@_Phillter Thanks for the reply. I can imagine that it's a lot of paperwork.

[@strongbrew9116]

@@edam9461 That's interesting. Are you considering going above 10kWh?

[@peterverbogt3870]

Hello Matt, As we build our "passive" house back in 2016-2018 we know what it is to live in one. My question, how are you controlling humidity? As air tight houses react very different then old. In summer no need with humidity between 40-50% but in winter and spring it can easily drop to 20-30%. As we added a big humidifier most hvacs don't have a controlled function for this. Keep this in mind. Second is a net zero in kwh or dollars. As solar in the summer is becoming less and less profitable. Net zero kwh doesn't say that much anymore. With the small heatpump we have its using around 200kWh a week in the winter, no need to put a battery next to it. Good luck with the build its the best thing you can do during your lifetime! Greetings Peter

[@pondguru]

The term 'Net Zero' is pure nonsense since CO2 was produced during all the manufacturing processes of everything we use to set up 'Sustainable' houses. Unless we all stop breathing there will never be 'Net Zero'. However, having some sort of reduced home running costs, energy sovereignty and long term security in the event of a grid-down situation is always a great investment. Good one, man.

[@allenmgrayson]

Bought a 13 year old home North of Charlotte, NC. Lived in it for 5 years. Add a Water Furnace system (closed loop, 9 feet down) and our energy bill dropped between 32 & 36 %. My experience with Water Furnace equipment was excellent. Enjoy your channel good luck with your new house.

[@edwardbarton1680]

When planning your "smart home" with IoT, you should make sure to keep the IoT devices separate from your main network. IoT has a lot of advantages, but they also come with a lot of security issues. I use a VLAN for my IoT devices (VLAN 107, obviously).

[@inferno7181]

In general, avoid IoT as much as physically possible

[@drobinson4y]

What about 107 is obvious?

[@MallocArray]

@@drobinson4y I was wondering the same thing

[@vRxUniQueZ]

@@drobinson4y 107 looks like IOT

[@nasonguy]

My IoT vlan is 666.

[@necrojoe]

I also live in California and we dis a major remodel. Our home was built in 1959, and the only insulation was a thin layer in the ceiling. When we remodeled, we put insulation in every wall we opened, and added better insulation in the ceiling. The improvement has been HUGE! On hot summer days, our oldish home stays relatively cooler all day, especially if we "bank" coolness by opening windows at night, like a "reverse thermal battery". So glad we did it, even in California. So worth it.

[@doingtimeforsixty9]

Hey Matt, love you taking the time to review all of these awesome standards with everyone! I've been nose deep in all the topics you've touched on in this video, I've done new builds and am in the process of rehabbing an older home. If you did want to brainstorm on some of these topics let me know! There's a lot more little tidbits which could help you be more passive in the long run. Side note, the Passive House Institute is not american its a German company who also has reps in the US. That's why the standards between the two are so different.

[@rick-em5cw]

Wow I am glad to see this post. We are attempting to build a passive net zero home. Your video was an excellent sounding board. We are not crazy in attempting this. We have had it with poorly insulated homes and air blowing heat/cooling. We are currently laying our slab and will begin vertical construction in about 4 weeks. We are using T-Studs in place of 2x6 lumber to provided the thermal break. Zip R-3 with 3 inches of close cell and finish it of with mineral wool. The roof has two layers of zip sheathing with 4 inches of Atlas Iso Poly sandwiched betwwen and 3 inches of close cell with the mineral wool for the attic ceiling. The house has R30 walls and a R40 roof. The slab is ground insulated with close cell, foam and vapor/termite barrier. Ground Source Heat pumps, loop field, 2 EVR's HEPA filters, geothermal heating and cooling through a warmboard radiant floor system, domestic hot water via GSHP. 20 KWH solar array, 54K battery backup. Span load centers and Unifi network and protect integrated into the house. No NATURAL GAS! In doing the net zero approach I have run into a couple of concerns wondering how you are handling? The property has 700 amps-3 meters; 400 amps for the home, 200 amps for the well, barn & vineyard and 100 amps EV charging. My first issue is the solar/battery setup. I was totally unaware of the limitation solar has with anything over 200 amps. I will have 2 span load centers on the back end of the 400 amp box. It is complicated in deciding what go into which breaker box and how much soar and battery goes to each box. Did you exceed 200 amps, how did you handle? Things like the induction cooktop vent, dryer vent and bathroom vents create makeup air issues. The bathroom fans went to one of the EVR's but the cooktop and dryer took some engineering and dampers to accomplish. Is there an easier way? Looking forward in following this post.

[@gamertd4093]

I just want to chime in as a career electrician. Unless things have changed in the last couple of years with engineering designs of electrical systems in modular homes, I’ve found in the vast majority of cases that if you want to add anything years after the installation of the home, that it makes the addition of whatever circuit a complete nightmare for your local worker. Nearly every time I’ve been called out to add lights or outlets of any variety into a modular home it’s always been a LOT more cutting the rock than anyone involved originally thinks about. I’ve always thought the idea was really cool, and considered buying one when my wife and I were looking for our first house, but that alone kept me from it. I’d be super super interested in learning differently from other people if someone’s willing to point to an up to date article for me tho!

[@andrewfischer8564]

this electrician agrees

[@bearcubdaycare]

I wonder if the design should be different to allow future wiring. Built in extra conduits throughout, perhaps? Sorry for the non expert speculation, but it sounds like it should be feasible for them to design better for future unpredictable wiring needs.

[@Jynirac]

We are looking to build a modular this spring. Is this issue just because of lack of access panels? I was just hoping you could elaborate on the issues. Maybe I could have them addressed in advanced. Thanks.

[@kevinc-727]

In a modular home, even adding a WiFi where it should go for coverage can be impossible if Cat6 wiring not added during build, and forget moving a WiFi to improve coverage

[@gamertd4093]

@@bearcubdaycare the problem is specifically that each modular section is designed to be its own single ecosystem. Meaning that most of the time there is design constraints involved with putting further conduits in corner studs just for future wiring. That and the added cost of having an engineer design that.

[@scifithoughts3611]

We’ve put a lot of money on our house the last twelve months too: new roof, solar, half of the windows replaced with energy efficient ones, radiant barrier in the attic, and a swimming pool. So yeah, we are broke now but happy. We probably should have done some of that work later, but when you do that, many things cost more later. And while the price of solar keeps going down, your not getting advantage of creating your own power. Overall, my advice to everyone is get solar when you get a new roof (or shortly there after). The windows made a huge difference in energy loss (we only had single pane windows). But I’ll need to wait before I can afford to replace the rest of the windows. Cool project Matt and Two Bit Davinci! I look forward to watching your videos. It’s nice to seeing some of my favorite KZbin personalities working together!

[@BerenElendilAPGaming]

Matt, your sustainable home design videos have shown me something fundamentally important as a current architecture student: how relatively simple, near-term (reaching full adoption during my time working) and sensible a lot of these solutions are. My professors all make such a big deal about these kinds of advancements, but -- while they are, admittedly -- I think they also neglect to mention how much basic sense they make in favor making them seem big and important.

[@jimba6486]

Other than Thomas Sowell. I've never heard of a professor disapprove of any technological advancement because cost is irrelevant to them.

[@angrydragonslayer]

​@@jimba6486 my profs were terrifying in that way They were totally fine with turning off life support devices if it meant slightly decreasing fossil fuel usage Luckily for humanity, most building method innovations are win-win and only regulation causes any real issues

[@suchdevelopments]

Thanks!

[@keyem4504]

I built an apartment house in passive house standard some years ago with a PHI certified architect. The experience was great. We hit the budget spot on and the best thing really was the quality control and the quality of the used materials. And my tenants probably love me for it right now. 😏

[@bwilkerson]

I am in the middle of building what should be a net zero home. I used the free government tool BEOPT to model the energy needs and optimize the various options. Using this software has helped me chose cost effective options. In my case the numbers did not justify an HRV, but then I don’t have the allergy problems. Hopefully the energy model will come in close to reality. Sheetrock is now primed so we are getting close. One choice I am really happy with is a Sol-Ark 15k inverter with a built in whole house transfer switch along with battery and generator interface all in one box.

[@mrdog4849]

Very timely Matt. Been watching your channel for a few years now, and while we independently arrived at the idea of a passive house, it's always interesting to hear about other people's journeys. We have designs, planning approval and pricing for our passive house. We were originally going with prefabbed PH panels (from an Australian company called Carbonlite), but opted for directly engaging a certified builder. Then came Covid. The difference between the price estimate when we started (late 2019) and the pricing from the builder (mid 2022) was initially over double (long story), which after design compromises and engineering changes became 1.5 x the original price. Project duration doubled from 9 months to 18 months due to materials and trade availability, and this directly impacted the total project cost (keeping the project alive, providing updates, insurance, etc., etc.). Then came interest rate rises. So we have decided to put our build on hold for now, and buy a house to live in for now and keep or sell later. Then we heard that Carbonlite was building locally (after being told previously that they didn't build in our area) so have contacted them for a quote. When asked about budget we suggested 1.2 x our original price estimate and they "sounds more than reasonable", so now we are scratching our heads about whether to un-pause sooner rather than later. Time will tell.

[@johnravensbergen3324]

I designed and built a passive solar home based on the design in James Kachadorian's book "the passive solar house". If you haven't read it, I would recommend it. We have been in the home for 20 yrs. Biggest surprise "win" is a bright warm(26C+ by choice) house in the winter to compensate for the short cold days due to large south facing windows. We are not net zero, but 75% of the heating comes via the sun. Also tend to keep the house much warmer than we otherwise would. Biggest surprise "loss" - will not recover our initial capital investment with energy saving, as I didn't anticipate that staying connected to power and gas even if you use little is a significant cost (Canada). Would do it again! Love our home - good luck with your project.

[@simplethings3730]

I'm happy to join you in your fiendish plot to save the planet. When Texas lost power in 2021, I had 600 watts of off grid solar. Since then I've added another 300 watts and switched to 10 KWh's of lithium batteries. Since I'm poor I have to do this a piece at a time but eventually I will be self sufficient. The first solar panel I bought was around 1989. It was 50 watts and cost over $300 at the time. I still use it to keep the tractor battery topped up and it still puts out close to 50 watts.

[@absalomdraconis]

Keep an eye out on sodium-ion batteries (should be cheaper but heavier than lithium for a given capacity, if they reach the market), salt-cycle air conditioning, and of course I'd recommend a solar water heater system as a _preheater_ to your normal system. Greetings from Oklahoma.

[@62Deepblue]

Matt, love you channel!! I built a home 12 years ago, Gold Coast, Australia. Achieved an energy rating of 8.5 out of 10 and a reward for sustainability. Looking at upgrading solar to a 13.5 of 15 KW system with the option add battery. The home is designed and positioned to take advantage of passive heating during the window (even though with a subtropical climate it never really gets exceptionally cold). Like yourself I have found with solar you need to do a lot of your own research. The information out there is kind of random. No one seems to have a complete overall, holistic understanding of how all the parts of the puzzle integrate together. A very useful way to look at projects is to use sustainable systems thinking. Essentially to start you draw a mind map showing all the parts and subparts involved in the build, including all the stakeholders both internal and externally. You then draw in the different areas, using arrows, which interact with each other, sometime it is two way. When you step back and look at the system ,as a whole in a holistic way, you will see some very surprising outcomes and potentially a chance to avoid potential conflicts and pitfalls. And one last thing, in recent times research is showing the connection with our gut and out health. Basically imbalances show up as health issues!! Looked into during Covid!! Look forward to seeing and hearing more!!

[@davebryer6133]

We are doing the same thing as your friend is by doing a deep energy retrofit. It is the wrong time as prices of just the batteies and the SPAN pannel jumped about 7K in just a couple of weeks. But just to get from planning to the start of work took nearly 3 years, so it was time to do it. Looking forward to my project is finished and forward to your upcoming videos.

[@brianhaygood183]

I've had a Waterfurnace for almost 9 years now. They've done great with a couple of warranty items, and the system has run very well overall. When the AC is running, the heat you are removing from the house is used to heat the water in the water heater. When the heater is running, a small amount of the system's capacity can be used to create hot water at about the same price overall as a natural gas heater. I have a natural gas water heater, so in Winter it is a wash, but saves some in the Summer, in theory. Since I live in Texas, the AC is running most of the year, so that's a win. Most homes don't need an ERV because their air changes happen accidentally though leaky construction. However, having a super low ACH means you don't get fresh air leaking in. The benefits to the low ACH are huge. Instead of moist unfiltered air sneaking in, you've blocked that and are brining in air on purpose through air filters and to the AC system where its humidity can be controlled. Allergy sufferers will clearly be expected to benefit from this. Leaked in moist air is often to blame for rot and mold build up. Obviously not good things. Finally, instead of leaking in and equilibrating with the room air, then heading back to the HVAC system at room temperature, the outdoor air will come in at outdoor air temps. This larger difference from the HVAC supply temp makes for more efficient heat exchange. All very good stuff, and surprisingly not absurdly expensive.

[@binomial]

You should definitely consider aerobarrier as part of the air tightness requirement. They pressurize a house with air born sealant which fills in cracks upto 0.75 inch wide. Matt Risinger has a demo of the improvements to air tightness and it's very impressive. If I recall his new build personal house went from ~1 AHC 50 to under 0.2 AHC 50 after using aerobarrier.

[@D-B-Cooper]

Whatever happened to off gassing?

[@skysoldier31]

@@D-B-Cooper One of the principles of Net Zero homes is the fact that it is going to ve scealed and controlled. This means you choose materials that can coexist with you with the least amount of offgassing as practically possible. Any offgassing is taken out in the controlled environment of the home as recycled air.

[@NickRoman]

Well, Matt did say that he could get fresh air with his system (and it would somehow retain the heat (during winter I presume)).

[@OG_lemur]

@@NickRoman from some diagrams i've seen, exhaust air can be used to preheat fresh air prior to hitting HVAC by overlapping the extraction system with the intake. How well this works idk? But this supposedly reduces the heat loss of cycling fresh air in.

[@benhook1013]

@@OG_lemur Idk why he was cagey about the system to transfer the exhaust heat to the intake air, its called a heat exchanger and its a pretty common tech that hes covered in other videos Im pretty sure.

[@Eric-xp1kl]

Hi Matt, my wife and I built a new house 4 years ago. We wanted to build in a specific neighborhood and thus had to use the development builder. This builder was willing to work with us to build a very strong home as we are 1/4 mile from the ocean, but also very energy efficient. We ended up encapsulating the entire envelope from slab to rafters with CC spray foam, we did lots of sealing, used quality impact windows, etc, and put on 9.4 KW of LG solar. We have ~2,700 sq. ft but heat/cool more on a scale of a 4,000 sq. ft home. All this being said, we are Net Zero on electricity on an annual basis, and only use a small amount of NG for cooktop cooking and hot water. I also looked at Water Furance but 4 yrs. ago, the cost in our area was astronomical vs an American Standard 18 SEER. I guess I am curious why your solar has to be so large if your building is so efficient. Blower door test...we ended up at 1.0 which I think is fantastic for what is really a modified standard build. I have a friend who builds hurricane homes, highly efficient (mostly a concrete home), and gets blower door tests in the 0.4 -0.5 range. Best of luck with your build.

[@Orchardman53]

Matt, My house was built once 215 years ago, it is a monster to heat with single glazing and solid stone walls, but now we we're starting to upgrade the insulation. However one question that comes to mind is how many times your home will be rebuilt in 215 years and what is the carbon load arising from the rebuilds?

[@ooooneeee]

Great question. It should last long it at least be much easier to refurbish than current old houses

[@Tailspin80]

When it was built people would not have expected to heat it, other than huddling round an open fireplace then loading the coals into a bed warming pan before they went to bed.

[@sandypatience]

@@Tailspin80 Absolutely right. We're now all very used to central heating where the entire internal atmosphere is warmed through convection heating from radiators. Our ancestors sat in front of the fire and experienced direct radiant heating instead- hence 'wingback' chairs to cut down colder air flowing down your neck from behind. Most older forms of construction follows on from that including little insulation and very leaky doors and windows. Here in England a very well known clerical diarist in the 19th Century complains about ice on his bath at the bottom of his bed and how the shards scratched his skin when he got in. And then he goes off to his church in Hereford and delivers his Christmas Day address.

[@mnorma12]

I’ve researched all these things for over a decade. Passive, modular, geothermal, HRVs, etc. It used to make sense to spend significant $$ on super efficiency, but now with crazy cheap solar, I’d recommend just getting electrifying everything and getting a big solar array. It’s definitely the cheapest way to go net zero.

[@encellon]

It's not quite as hard as it sounds -- at least here, outside of Boston. The key for us has been doing what we can as resources allow -- not every last thing right away. Attic insulation, better windows, and stopping air leaks went a long way. After that, for all of 100 watts, adding a ceiling-mounted attic fan to drag in nighttime air cools the house like a 100-ton brick and saves a bunch on AC (like 80-90%). The rest is still in the works... adding south-facing windows with roof awnings to allow winter heat while blocking the summer sunlight. Adding heat pumps to manage extremes of heating and cooling. Solar electric panels are coming online next week -- by far the most expensive step -- but worth the investment. With a net-metering installation and everything else we have planned, we are likely to push our utility bills to nearly zero. Solar hot water is strangely the hardest. It doesn't cost that much to heat hot water, so the investment takes 15 years to repay (about the life of most installations) and it also needs a backup heater - so the expense is hard to justify. The same investment return is true for gas stoves, driers, and hot tub heaters. Alternatives are expensive and the savings are minimal. Am I talking about net-zero? Not exactly since we are banking electricity with a uitility that will return it using fossil fuel and we will be burning a small amount of natural gas. But we are mostly reducing our carbon footprint while cutting our monthly expenses to nearly nothing.

[@tzehr2617]

When deciding on what smart components to add, keep in mind that they’ll all eventually fail and/or associated software will become unsupported, requiring eventual replacement (probably at an inopportune time). I was interested in electrical smart panels, but decided smart breakers placed in a normal electrical panel would make better sense. Much easier to replace/upgrade individual breakers than to replace an entire panel.

[@kaf2303]

You won’t regret it! I designed & built a super insulated/passive solar house in the late 80s in Vermont heated with solar & wood heat (1.5 cords ) it has saved a lot . Recently I have added 31kw of pv solar and sell enough excess power for my home & 5 neighbors. Best of luck with your home,

[@zale76]

We live in near passive house since 2012. We have Nilan VP18 unit, which is heat pump air-air with hot water tank of 180 liters (all in one). It also works as AC unit with 1 kW output and the heat is used to heat the water in summer months. Our consumption is 5 MWh (125 sqm, 3-5 persons). As mentioned in video, house was about 15% more expensive than conventional build at that time. Photovoltaics did not make economical sense in the past, but since Russian invation energy prices went crazy in Europe, so I'm considering to installing it, but legislation in Czech republic is very unfair for small energy producers.

[@88COR88]

I am financially conservative and NOT an early adopter so I'm very thankful for people like Matt that blaze a trail in the right direction while not knowing if their trail is the best one. When I hear about these projects my first thought is payback time frame. If you have to live in the house for 20+ years to get the benefit I don't see that as realistic. Most people move for a whole host of reasons in their lifetime. Most housing prices are based on comparative homes in your area so if you're a trailblazer your home will not see the increased value for awhile, if ever (see below). When I installed a full solar system 8 years ago it was because of the generous rebates my state offered. When I went to refinance my home a year or so later I found the installers claims that it would increase the value of my home was a lie. I confirmed with 3 appraisers that not enough home in my area had sold with solar systems to be able to evaluate the comparative value so they assign zero value to the system. The good news is recently I've seen some value being assigned to solar systems but still don't know how much. When you are on the cutting edge you have to hope you are selecting the technology the rest of the market will agree on. Think Betamax vs VHS tapes. Even if you pick the better standard if the market picks a different one, long term maintenance on your system become dramatically more expensive and may require an expensive replacement down the road. Few people will want to buy a home built to the "wrong" standard. Also, many of the standards you build to have not been time tested so we can only guess at the long term maintenance cost. For example pulling numbers out of the air: Say a standard home costs .5% of it's value a year to maintain. Since a net zero home is built to higher tolerances what if it costs 1.5% a year to maintain those tolerances after 5 years? It might be like maintaining a Honda verses a Porsche. As I see it, the long term value of these technologies is if we can raise the standard for new homes so they start off more efficient. The economies of scale brought along with constructing 100s of homes to these standards will bring down cost and make it a better long term investment. Early adopters like Matt will help give us the data needed to justify the increase in building standards.

[@arossnagl]

I mean geothermal, energy recovery, thermal bridging, high R value and air tightness are all age old technology. Most of it since at least the 70s and much of it required by code in varying amounts. The security, blinds, etc are consumable fun in my opinion. But if he had to sell earlier then he thought thats the stuff that might get him $$$$. Our realtor did tell us that younger buyers were looking for efficiency with gas bills up so high.

[@TheMalT75]

Good luck with your project. We invested almost 3 years ago in a 10kW photovoltaic solution with a 10kWh battery for our 4 person home. A couple of things I would have loved to have known before and you might not yet have them factored in: most appliances run on AC power and PV+battery is DC. So, your inverter(s) need(s) to be able to power whatever you want to run in parallel. While it is not difficult to get used to not being able to cook on your induction stove, have a dish washer and tumble dryer run at the same time, it sometimes can be an inconvenience. In our case, we produce hot water via electricity, which means even in the summer we need to draw power from the grid because 14kW water heaters are more then our 6kW inverter can handle. The second surprise is how inefficient PV is in the dark season and during bad weather. In summer, your battery will likely never run below 50% state-of-charge, while in winter it might only seldomly go above 50%. Your house battery should be considered a "backup" to power standby (or smart-home) systems through the night, but will likely not be enough to get you over a two-day stretch of overcast sky. I hope you can get a good deal on selling superfluous electricity to your grid electricity provider, because to be an insular power generator during the dark season, your PV solution will be massively over-designed during summer. While it is a nice goal to reduce emissions as much as possible, currently there is no "good" way to store electricity on a per-home basis for the half-a-year seasonal change in PV production. If you take the cost and capacity of your home battery and its expected charging cycle lifetime, you can calculate the cost of stored electricity per kWh. For us it was around the 24cent/kWh mark. Factoring in the ~85% round-trip efficiency of the battery and 8cent/kWh we get for selling produced electricity, using the battery is marginally more expensive that relying on the power grid. I would be surprised if you currently can beat the cost of whatever your provider charges per kWh! How that will evolve is anyones guess and while the cost of electricity is expected to rise, it might turn out that in a couple of years with carbon-free electricity provided, its cost could actually plummet...

[@davidlawrence2764]

This series is awesome for me. We just bought some land in Vermont with the idea of building a passive house using a prefab company. We have time as we live in Texas and aren’t moving for 5-6 years. Like you I have been researching passive houses and even trying to retrofit my current house. We have a large solar system with 3 batteries but the house is poorly insulated. Thanks for this series!

[@harrygoldhagen2732]

Vermont is a great place to build a home! Consider geothermal, it gets a little colder here than in Texas...

[@TheHorseshoePartyUK]

@@harrygoldhagen2732 Something I've had going round and round my mind for a year now, is the possibility of either bladeless or vertical-axis wind turbines, at home-scale. Especially over in the USA where you lot generally have much, more land available on average. I'm thinking of a design perhaps not much larger than 12 feet, if at all. We can get some amount of electricity from this, especially with more than one unit, in our own yards! Combine this with a good cheaper, if less sleek home battery than lithium tech, and other renewables and surely it's a winner? The silly TRIGGERED NIMBY types don't get to complain about it being an eyesore, even as they are a loud and vocal, small minority about regular wind turbines.

[@cyberslim7955]

Why build a passive house, when you can generate the energy on the roof? In Germany in the 80s passive houses where the hot thing before solar became so super cheap and sole to water heat pumps for heating and cooling became so efficient.

[@TwilightMysts]

I still hope to build an Earthship based home in the future. I won't be doing all of the recycling elements, but I want to use a lot of the energy efficiency elements... * The greenhouse front. * Earth-berming * Rain-water collection * Multi-stage water use system * Solar water heating * Photovoltaic power * Passive solar heating * Rocket mass heater as backup, possibly combined with in-floor radiant heating. * Buried cooling tubes * I would keep the glass bottle walls as they are really pretty. Some differences though * Rammed earth walls instead of packed tire walls * 12 inches of mycelium straw insulation in the walls * I want a heat recovery system, but not sure if it will be compatible with earthship cooling tubes and convection currents. * May put 6 inches of soil on the roof * Would like an alternative to the blackwater toilets (either composting or incinerating) Probably other changes, but that is what comes to mind so far.

[@aleenaprasannan2146]

I'm from South India with a very humid tropical climate and since we don't have extreme temperatures natural ventilation is still pretty much the main temperature control system. It's also pretty much a necessity to avoid fungus since we get a lot of rain. Almost all homes are brick and mortar. Air-conditioning is still used minimaly only for bedrooms and only during the height of summer. So the entire home being completely airtight, in our context would actually need more energy for need of Air-conditioning the whole house to ensure air circulation. I'm really curious if there is any data on energy expenditure of sure such naturally ventilated homes and what measure are there to retrofit them to be more passive, since maintaining existing building that are less energy consuming is more sustainable than building a brand new passive home

[@gracilism]

The answer is dedicated dehumidifier and an ERV (energy recovery ventilator). Making an airtight house with the proper mechanical systems gets expensive quickly.

[@aleenaprasannan2146]

@@gracilism I don't know much about EVR systems, but from what I've read it pre-cools and dehumidifies during summer and humidifies and pre-heats during cooler months. But we are in tropical climate and our cooler months are also wet monsoons and our warmer seasons are humid sweaty summers. So we need dehumidifying without cooling a heck lot more during cooler wetter monsoons, and controlled humidity with cooling during warmer weathers. Are there any ERV systems that work in that way?

[@Uagiant]

@@aleenaprasannan2146 ERV from what I understand is mainly used for the humidity and making the home "feel" closer to the temperature you want. So it would remove heat and moisture on the hot muggy summer days. The "steam" or water vapor has energy within it so removing that from the home will lower the total energy and heat in the air. It could be useful in your case, but a dehumidifier alone may do some of the work, yet less efficiently. I don't know that much ERV though as I just started learning about them.

[@mediacenter3592]

the solutions I've seen in Indonesia that have a similar climate to yourself aren't to try and fight the environment by creating a hermetically sealed, air conditioned bunker for your whole home. You're already on the right track by prioritizing air conditioning for a bedroom or small living area only. It is much easier and more efficient to create small dwellings (or rooms) on a property that are air tight and heavily insulated. Then, using a solar array, you can power air conditioning and air treatment to those heavily insulated and sealed areas. The rest of your home should stay passively cooled and those small treated areas are your oasis' from the heat and humidity. This makes obtaining these comfortable spaces possible without trying to fight mould and humidity throughout your entire home and also make it more economical since you're only doing so for a small space.

[@marthamryglod291]

I've been in home building for my whole life. The way that your homes are built can be optimized, but work well with the primary method of passive cooling. Improvement can be found by continuing to use passive cooling, while decreasing the impact of solar gain in the structure. When air conditioning is used, it won't have to work as hard to cool from ambient temperature. Improvement in air sealing in bedrooms with windows and doors closed will help cool the room faster with less energy. The room should still be able to ventilate well when the door and windows are open. Our family property in the Mediterranean climate of coastal California was built using passive methods in 1890. In summer, the house was comfortable except on the hottest of days.

[@pismomann]

Added 3 inches RF on exterior Added 1 1/2 inches RF interior ( exterior walls & ceiling) Added 2 inches of RF under my 24 gauge steel roof. 3 inches of RF added to crawl space. On Vancouver Island

[@docw6055]

Thanks Matt for giving us this update. I was going back and forth with Ricky about his project earlier in the year, and have been waiting for you to let us know more about your plans. I’ve followed Ted Benson for over forty years (my wife and I almost took one of his timber frame workshops way back when), and I think it’s great you’re able to work with Uniity. I’d actually love to be able to come see your place as you progress through the build; I think we’re pretty close to you. Anyway, I’m looking forward to seeing how this all comes together.

[@jhnsbrgr3100]

we have just finished year one living in our netzero home here in Vermont. Same idea behind it -- lower running costs, warmer during the winter, all electrical, nearly-passivehaus. So far it has been great. I think we will need to add some more solar panels as our electric use (running computers in our home office have mostly added the additional cost) down the road but overall it has been very cheap to operate and live in. We timed things about as well as possible with buying the property in 2018, completing design during the pandemic and locking in material pricing right before the pandemic hit. We have a Zehnder ComfoAir ERV and two heat pumps (one upstairs and one down) and a few ambient floors. We have a fireplace, dryer vent and range hood which took passivehaus out of the picture for us but it works much better for how we live and have no regrets on those choices. Last year, the house kept its heat even when it was down to -30F over night a few nights.

[@sctexan5392]

I'm doing the same thing, just much earlier in the process. We're likely a couple of years away from ground breaking. Currently gathering information (so this series will help), searching for the perfect lot, and researching what technology we want and can afford.

[@primozstanonik]

Just do it. Dont be afraid of anything. Me and my wife build (finished) our house a few years ago. I used natural maerials. Rethink before you start and you will still try to change some thing when you finish ;). I recomend Heat pump 8KW max. (underfloar heating 22drg.C max.) + photovoltaic pannels on the roof(10 panels = 10KW). Build a small chimney in case you want frestanding fireplace at old age ;). I live in Alps so we have cold winters but I wouldn change enithing. Most important is qualiti made facade (minimum 15 cm thick), 3layer windovs and insulation on the roof.

[@ab-tf5fl]

For those that can't even afford a down payment on a house, there is a simpler, cheaper option available that also greatly reduces energy consumption. Simply living in a multi-family building and sharing walls with neighbors provides a huge energy efficiency benefit, even without the passive house design. On mildly cool days, you can even shut off your heater entirely and just collect free heat from your neighbors through the walls.

[@piraterubberduck6056]

This is actually a really good point. If you have a party wall you reduce the area losing heat significantly.

[@jonathanburr9798]

This is a huge point - just to expand on why is it: you house has to deal will all exterior surfaces - that's what the insulation handles. If you are a duplex - one side of your house is suddenly not outside - so you don't have to manage that and your efficiency is one side of all 6 less - 16.7% better. In an appartment setting, the worst efficient corner units have 3 exposed of 6 sides - so 50% better, up to 1 of 6 for 83% better. Just by living in an apartment that could be extremely large and be the same floor area of a single family home - you can reduce heating/cooling energy use by 83% - that's massive.

[@circuitdotlt]

It's called an apartment, not a house...

[@necrojoe]

I mean...by "collecting heat" through the wall means your neighbor is having to pay more for their heater to run harder to keep up with the energy loss through the wall.

[@randomcow505]

thats not free chief, thats making them pay to heat your home its gotta come from somewhere and if you turn yours off, your gonna be sinking the heat from them, so they have to have theres on more

[@valerimacdonald5146]

We are in the process of designing our Passive House and are undecided about whether to go modular or on-site stick built. The modular manufacturer is over 1300 miles away, so while modular can reduce the size of the "worry box" in the build, if there are problems, it will be difficult to help us on site. We too will not be trying to meet (Canadian) Passive House certification standards. That seems to be a lot of hoop jumping for questionable benefits. The good news is you can now get windows and doors from North American manufacturers that qualify for Passive House. Again, that gives me some comfort if there are any issues with the windows or doors. I think this is a sign that Passive House is trending.

[@jamesdorsey7145]

Good luck with your build! We just finished our home a few months ago and, though we weren’t aiming for net zero, we did have air quality as a serious priority. Both my son and I have allergies, and we live in East Bay, CA. Preparing for all of the dust and smoke that comes with living in here was very important. We ended up going with a heat pump system (that has filters for Hospital level air scrubbing) and an erv for days that don’t require heat or cooling with a filter for pollen. I’m totally jealous of your geothermal set up, btw. I really wanted to do that here but the cost of soil removal + permits were not in the budget. We insulated with rock wool, wrapped the house in Henry blue skin and have a stucco exterior (most homes here do). We didn’t condition the attic 😕. Still, whenever it’s super dusty and smoky my son and I can stay inside an breathe easy. It’s been an amazing change. I look forward to seeing your project unfold, and thank you for the information that led us to making some of the decisions we made for construction!

[@seldoon_nemar]

Matt, there's a company called Aero Barrier that can help with that ACH score. They have a system where while doing a blower door test, they set up sprayers and aerosolize a 2 part product that when it's mixed by air movement will creat an epoxy caulk (I'm not the expert, just a fan of it), so while the air is being forced out cracks from the blower door, it's sealing them. they claim to be able to take a house down to 0.1ACH even if they start with a 2 or 3. mind you, you're paying for the amount of time the system is running so starting tighter and is obviously better and it's instant data. they just run the blower door to get a before score, do the process, then get an after score. all in one day

[@ssoffshore5111]

Very exciting Matt! I'm looking forward to watching both builds on both channels... You guys are lucky to get to double dip using YT! 😄 I just resided the house this summer and took the opportunity to add 1.5" of GPS (R 7.5) to the exterior. I already have noticed a little difference over the summer, but looking forward to seeing how much of a difference it makes this winter (located in CT). Solar is next up, SA 15k and around 15kW worth of panels on hand, I just need the time to get it all installed! This 1935 house will never compare to your build, but trying to do it on a budget and maximize the bang for the buck (while also keeping resale in mind)!

[@berthaduniverse]

We're in southern California, at about 2000', and we use open windows and a whole house fan through the night (in the summer) and almost no heat in the winter. We have installed attic insulation up to R60 to keep the heat load down, and have a large solar array so our electricity is essentially free. Working to create a net-zero (on an existing) home here would be wasteful and cost prohibitive. One nice feature of a net-zero is a much quieter home, but it can almost be too quiet. So I would say, air exchange is often a very good thing, and in the deserts SW, the more passive it is the better.

[@extendedp1]

I would like to build a Passive home someday, but your cost estimate was misleading. The Passive house isn’t 16% more expensive it is almost 100% more expensive, $84 a SqFt vs $159 SqFt. Your video title is also pretty “clickbaity”, and you didn’t give very much information about your passive house build, or even a passive house in general, considering the length of this video.

[@trumanhw]

I search for another commenter who paid attn (by searching: _159_ ). This guy called paying just under double ... 16% 🤣 (as you noted). Basically, you reduce cost the most by first insulating, then, maybe triple pane insulated windows (research) Get a thermal camera to look for the areas to work on... Search for a service to test how 'leaky' your home is (how much air cycles through it). All of which should be done BEFORE solar BS, bc it's a 1x cost that makes everything more efficient.

[@ShortVersion1]

We've been going the Ricky route for the past couple years. Instead of targeting the Enerphit specific criteria, we're slowly aiming for net-zero (not water). After some insulation, windows, ASHP, batteries, and solar... we're at 28 kwh/(m2a) for all of our energy including natgas and EV charging. Enerphit says our zone should be 25 kwh/(m2a) for just heating demand. IDK about air tightness in air-change/hour, but it's getting better all the time. Just ordered some IR panels to play with, and further down the line will switch out dryer and water heater for heat-pump versions. That should let us seal their vent holes, and hopefully reduce net-energy to ~12 kwh/(m2a). All that being said, I'm super stoked to see how low you get the new build's consumption. My parents are currently building in the Southeast, and getting contractors to build airtight, and supply houses to carry cutting-edge products has been an uphill battle. Cheers Matt!

[@482jpsquared]

My wife and I built a certified Net-Zero home in Massachusetts. It was also built in a factory. We have no regrets with that choice. Let me know if you would like to discuss our experience. All the best with your project, Matt!

[@davebeetle5262]

Who was your builder? Thinking of the same in VT.

[@482jpsquared]

@@davebeetle5262 I was the GC. We ordered modules from Preferred Building Systems in Claremont, NH. They have all kinds of options to achieve net-zero and even passive standards.

[@tennesseetexan1957]

What I would like to know is what was the price per sq ft ? All of this is great in principle, but how long does it take to pay for itself with the extra cost? If it takes more than 10 years then to me, it’s not worth it. Good insulation, zip systems and good windows are doable. Also, with my home, I faced the house south with lots of windows to make use of the sun to help heat the house with the low winter sun.

[@482jpsquared]

@@tennesseetexan1957 The price per SF is different across geographical markets. That said, our solar grid (about $40K) Tesla batteries (about $20K installed) will pay for themselves over 5-7 years. That is based on 2020 fuel prices and includes all the up-front incentives and clean energy credits in MA. We just shaved off about a year with rising fuel prices. It really is a no-brainer in most, if not all, cases IF you are able to come up with the $ up front. After the up-front investment recovery, we have literally free energy. All of our heating, cooling, electricity and car charging comes from our solar grid. Right now we pay nothing monthly for any of those and we see a check for about $250/mo from our utility company for the excess we generate. I estimate we would have paid about $800/mo for gas (heating), electricity (AC) and general electricity use (including car charging). That's about $10K/year. Hence the 5-7 year pay-off. The house itself is hard to factor into all of this, again due to different markets. The extra insulation wasn't a big deal, as the house was built in a factory. We used high efficiency windows (some three-paned) and Mitsubishi HyperHeat heat pumps. Those elements added maybe 20K in costs but we would have done those even if we weren't shooting for net-zero.

[@tennesseetexan1957]

@@482jpsquared sounds like a great deal in a place like yours where fuel & electricity are very expensive. Just remember you are paying for it until you break even. It’s not “ no cost”. Where I live gas & electricity are relatively cheap in comparison to your area so it’s not cost effective here. Decent houses can be built here for $100 per sq ft. But kudos to you for being able to do it where you are.

[@robertnystrom289]

I also live in central MA. I built mine back in 1991, starting with Mass Electric's (now Nat'l Grid) Energy crafted home. I took their building course (free, several weeks or a month's time) and they gave me the software to model the house (I'm an EE, so no issues with- gasp- DOS at the time). Due to contractor problems (they just didn't get it), it was a 3 year slog. Been through about 28 years of living with ERVs and HRV's. I've got lots of tips there! Foot thick double staggered 2x4 R35 walls; plastic vapor barrier behind the 'inside' 2x4 wall to make it more plumbing and electrical friendly- no sealed electrical boxes back then! This was a workaround so they wouldn't cut the vapor barrier. House is 3600 sq ft and about 50,000 cubic feet (yes, 50,000- I was into HIGH ceilings back then- 13 to 19'). Blower door test passed with flying colors. House was extremely quiet and efficient; very comfortable. Issues now, but I would do it again with one or two caveats. You can't just check your brain at the door- the house ventilation requires at least modest management, like if you want to open windows, don't open the window in the room with the exhaust duct(s)- you short circuit the whole air flow thing! Several stories on how to find the SMALLEST oil burner possible (no other options back then)- that was a REAL problem and a humorous story (involves heaters from RV's), along with the occupancy permit inspection- it failed because I didn't have enough baseboard heaters. He didn't want to hear about calculations or computer modeling (talk about an alien term back then). To pass, I put in fake baseboard. Lots of home brew 'smart home' electronics- I had home brew 'computers' on RS-485 links running through the house controlling everything (circa 1993!). Standby power was massive on my early designs (car batteries got me an hour or two). Lightning blew up my system twice- 1997 or so and around early 2000's. Revamped everything! Four split A/C's. LOTS of hard earned tips there, too! Do NOT do multi heads on one unit- bad idea. Do ONE condenser for EACH evaporator. I'll give you one hint on the ERV/HRV- make SURE you have spare everything- fans, control boards, etc. The house rapidly becomes unlivable if that thing quits! My original was a VanEE from Canada; parts were long and hard to come by. Where you locate the intake vent is absolutely critical, both for how 'fresh' the intake air is and how quickly you completely plug up the ventilator when you cut the grass! I have gone to an OUTDOOR intake filter- avoids condensation problems inside, and keeps crap (mold!) out of the intake duct. The filter has to be large- 20" x 20" x 4" to handle the 200 to 250 cfm flow and get decent filtering. Hint: have a kill switch! If someone is treating the lawn, you better be on that fast! And even faster when the dog gets sprayed by a skunk right outside the intake...

[@Anamnesia]

A former manager (in Australia) had built an off-plan Six-Star energy rated home. He’s the kind of guy who reads all the regulations from start to finish & is a stickler for detail... During construction he would attend the worksite & constantly hound the Builder on ALL the details the builder was “doing wrong” to code. Like having an apprentice fill wall cavities with off cuts of insulation, where the code for Six-Star energy homes requires a Tradesman certified in fitting insulation to cut out from an entire insulation sheet to snugly fit the wall cavity without gaps! The builder was so incensed that my boss wasn’t letting them get away with corner cutting, that they put locks on ALL the entry points during construction! But my boss still managed to get in to document/photograph every last construction issue.

[@janklamer]

PUR foam is your friend ;-) sometimes in retrofit you just cannot jack isolation snugly fit between beams etc. PUR foam is not as good as PIR, but it seals great.

[@IndigoIndustrial]

This is why I dislike 'tradies' who give trades people a bad name. In my new build place I found offcuts of wood and metal scrap behind panelling. There is also the way that they sit down anywhere for their lunch and proceed to engage in conversation any woman walking by.

[@Tom-ku8bu]

That would be the worst customer to have. If he knows it better so why doesn't teachs he the apprentice how to do it wright? Since it seems that he has time for it. Putting in isolation isn't that hard and I'm sure a good apprentice can learn it in less than a half hour. People who don't put their knowledge to practice always know it better even when they don't even try to do it better themselves to see where the shoe doesn't fit. Theory and practice are often two different shoes

[@Anamnesia]

​@@Tom-ku8bu Well, the building code for a Six-Star energy rated home states; the insulation *_MUST_* be installed by a licensed tradesman, using continuous (read: un-broken/uncut) sheets of insulation. The fact that the apprentice (non-certified) was installing cut insulation, and stuffing the cavities with offcuts... Well, you have to ask yourself, "Why are they charging the client *_extra_* for the Six-Star energy rating price, when it's not certified to that level?" 👀🤔🤷‍♂🤦‍♂

[@IndigoIndustrial]

@@Anamnesia If money changes hands, services must be rendered.

[@steverichmond7142]

I live in Scotland which is cold and damp. I have built 81 houses which are all airtight very cheaply. A good trick is to build 'shoe boxes' with cold roofs and use the roof decoratively. I use HRVS. Solar doesn't work because of cloud cover so I have built 6 detached houses with a shared wind turbine and where appropriate I have used ground source heat pumps for hot water. If not I heat water with instant water heaters. My son is French and he has built over 100 houses in the South where heat is the problem. We always use SIPs.

[@michaelholster5432]

Matt, am anxious to see your actual results. I am an Energy Engineer and finally have the chance to build my own energy efficient home, which is now under construction. Please include your energy utilization index in your results video.

[@dalenbickenbach9533]

Start watching the Global Passive House Accelerator.

[@hersenskim]

"energy engineer"... Sounds like one of those new made-up engineers like "software engineer" or the "sanitation engineer" that cleans the toilets

[@chrism6880]

I bought a home that was built in 1975. While I'm not going to obsess over full net-zero, i am working hard to retrofit it to be as efficient as possible. First, replacing the old gas appliances with heat pump electric. Next, I'll be encapsulating the crawl space and upgrading the insulation throughout the house. Eventually, ill add a smart breaker panel, battery backups, and solar

[@aaronbailey625]

Hi Matt, big fan of your channel! I love the sustainability and energy efficiency content you're sharing with us. One question - have you ever engaged with the broader perspective of extending sustainable and low energy housing on a societal scale? I'm also a big fan of channels like NotJustBikes and Climate Town, and I'd be interested in hearing your perspective on the intersection of energy efficient housing units and greater city/town design. There are still a lot of questions and concerns I have when considering housing sustainability like the overall cost and accessibility of upgrading buildings and providing energy storage with lithium batteries en masse. I'd love to see a video or videos touching these topics!

[@bcoldwell1]

I studied passive house designs for about a year, and considered Enerphit when I started my whole-house renovation 8 months ago. I agree....you spend a lot of time and money trying to squeeze out the last 10-15%, and that puts it out of reach for many people. In the end, as a thought experiment, I decided to target a 50% carbon reduction strategy by doing things that were in reach of most owners and contractors: ZipR before re-siding, to reduce thermal bridging and gain air tightness. New doors and windows, paying close attention to air sealing. Rooftop solar, and electric appliances (HP water heater, induction cook top). In the end, I chose to stay with super high efficiency nat gas heat, due to our cold MN winters, coupled with an HRV for fresh air and energy recovery. We'll see if I can hit my modest target......

[@luispenalozaambriz3254]

Hey Matt! When you are measuring your home’s carbon emissions are you also accounting for the emissions produce from the building material ?

[@GregEva]

I think you are thinking of Carbon Footprint... where Matt was talking about Carbon Emissions

[@charlessmith9134]

Hi Matt, I really have enjoyed your videos! Just a word of caution concerning geothermal. I strongly recommend that you thoroughly research hvac contractors doing geothermal. I have read of many horror stories of poor engineering of the loop system. I have had geothermal for 27 years and had a lot of trouble with both units. My main unit finally died and needed to be replaced. There were no geothermal dealers within 150 miles of where I live, so I chose to go with a variable speed Bosch system heat pump. Look online for geothermal forums for more info and by all means get a 10 year warranty!

[@adamsterdam9049]

I have been following Linus from LTT on his journey of adding tech to his new house, im excited to see your smart home videos

[@UndecidedMF]

👍

[@dougriedweg9002]

We built our version of energy saving home seven years ago . Icf walls , concrete floors with radiant floor heat , ground source heat pump. Really happy. Lastly we added 14 kw ground mounted solar. I did most the work.

[@jasemo388]

Are you still doing videos on energy storage? I'd love to see your take on the current status of flywheel energy storage. Their common use has been in short duration, hi-load industrial applications (such as UPS's and Physics labs) where standard mains power is insufficient. However recently newer more domestically suitable options have appeared. Particularly interesting are vacuum-sealed magnetic-bearing models which advertise impressive round-trip and mechanical efficiencies and indefinite working lifespans. However it's difficult for a layman to dispense with marketing bumf and get an apples to apples comparison with other storage technologies. Be great if you could take a look. :)

[@kennethwilson2385]

I built my home with insulated Concrete floor 4" all , Walls, Rockwool outside, 2" spray foam R19, Ceiling R 165, 1280 Sq Ft home Full Basement. Tin Roof. GO-thermal - Heat pump Solal panels Grid Tie. We have an electric bill of 0 to $36.00 even at 90%+ days. Winters 1 or two months it might get to 85.00 and that is 10 below range. Yes it cost more but worth it in the long run. As the cost goes up that makes this even more affordable.

[@crschoen123]

I would love to see a life cycle analysis of the carbon impact of new construction vs. renovation. The foundation/basement, material production, and material transportation components are probably the biggest constituents. I wonder if the retrofit approach actually saves more carbon compared to clearing a new plot.

[@ooooneeee]

Retrofitting probably has less emissions and if an old building was demolished to make room for the next, many tons of waste less too. I want him to calculate all the emissions and resources of building it into his net zero equation.

[@TheLosamatic]

@@ooooneeee compared to the carbon footprint of the original, you are including that right?

[@JoelCook]

@@ooooneeee that would be interesting information but constriction wouldn't go into a net zero calculation. Net zero is about annual energy usage vs energy production not carbon footprint.

[@crschoen123]

@@TheLosamatic I'm not sure that's relevant to the decision of building or renovating. You can't change the past. I would just be curious what would have the lower impact long term. My question would be: is demolishing a house/forest and building a new home that's more efficient produce more or less carbon than renovating

[@ooooneeee]

@@JoelCook idk I'm just used to lifecycle assessments of products and there the resources needed and emissions created to build them are usually included and are often quite substantial.

[@Frank-Y]

I bought a net zero house two years ago. With the energy prices here in Europe, I’m so happy with this house. Our energy bill is 5 euro a month. (5 dollar)

[@AndrewKuntzman]

I think both your plans will be fun. I have been to Ricky’s house and I can’t wait to see the future progress. He’s motivated me to do more at my house in colorado as well. Both of you guys have great plans

[@ASkippingRock]

My wife and I live in a kit house from Finland built in the late 1940’s. With new insulation, zip R sheathing, siding, windows, attic insulation, and electric heat pump the temperature control is incredible. Most of this happened in 2019 and 2020 so costs were lower. One big downside to retrofitting is the difficulty and expense of properly insulating the basement. Insulating the basement properly would require excavating all the way around the house to the footing. If we had purchased a modular we would have spent about the same amount of money but everything would have been new, the house bigger and the foundation would have been insulated with footing drains.

[@dixieflatline1189]

Great video & good luck with the build. An interesting comparison between your factory build and your friends home is the “embedded carbon” cost (assuming that the existing house only counts the embedded carbon cost for the retrofit, not the original frame & structure).

[@kdkd693]

We’re finishing building our new passively heated house here in W Australia. North facing windows with good design of eaves limits summer sun ingress and encourages winter sun to warm the heat sink flooring. As we have a much solar insolation as Phoenix AZ, and hot summers, cooling is key. Like you, I have bought a huge PV array (of 60 x 440 watt panels (cheap here), and 2x10kW Fronius 3 phase inverters to allow 22kW charging of my ordered Cybertruck. Similar to you, a 19kWh battery will get us through the night (BYD modular HVM). Everything in the house is electric, many heat pumps including a big one to heat the outdoor plunge pool in winter, a hot water heat pump and induction cooking. I strongly considered off grid to avoid the 11.5k connection infrastructure fee, but the extra cost of another 2 batteries (or 3 powerwalls) didn’t work economically. So will have grid to top up if needing extra charging power. Total solar system installed cost will be $38k AUD

[@jeffreymills2738]

Hey Matt - I’m starting to plan a retrofit on my 1920’s bungalow on a decent piece of land and wanting to get geo-thermal and get as close to net-zero as possible. I’d love a list of the components and companies you went with. I trust your opinion and it would be a big help.

[@terrencesicilia8972]

Hey Matt... Thank you for all of the great content in your videos... Just wanted to confirm your comments that this IS probably the worst time in my 50+ yr building career to construct a new home; we are going through a process of "Chasing the Numbers"... AND I am doing so for a friend to whom I have suggested that he adopt many of your ideas in his new 3,450 sq. ft. home over a finished 1,400 sq. ft. basement in North GA... Keep up the great work; Blessings...

[@JayJay-dp8ky]

I built my new home last year (2021). After consulting with Huey, I've decided to power it completely off love. It's a curious thing, sometimes it makes me weep and sometimes it makes me sing. Turned all the local hawks into doves though.

[@calholli]

I don't get it

[@michaelfried3123]

get back on your meds.

[@brianzmek7272]

@@calholli The Power of Love [Huey Lewis and the News] kzbin.info/www/bejne/Y3-woZtvaZinqdk

[@JayJay-dp8ky]

@@calholli When I first got it, it made me sad, Second time it just made me mad but now I'm glad I've got the power that makes the world go round.

[@MikeYoungeasytravel]

As a solar owner, I would highly recommend going with a smaller solar system and a bigger battery system. I had an 8 panel system (2.4K) installed in February 2022 and I have generated more power than I consumed each month, so far. My system costs (including installation) was €5,200. I see too many people, especially in the USA, purchase much bigger systems than they actually require.

[@davidreem7716]

I love the efficiency you can get with passive houses, but Ive always wondered, does that prevent you from having windows that open? I assume not, but that has been a little unclear to me. There is just something about having windows open in spring/early summer.

[@UndecidedMF]

You can absolutely have windows that open (I will). It's up to you when to open them or not. Ideally, you want to keep them closed most of the time though (depends on the temp/humidity difference between inside/outside).

[@retireorbust]

I would really like to have the European windows that open like a door or tilt

[@jonathanburr9798]

It actually really encourages opening the windows when it make sense it. The question is why you are opening windows? If its comfortable outside, then of course, go ahead and open windows. If it's below 0 outside - why would you open then window - same if it's during a heat wave. They account for the summer cool nights as a reccommended method for opening the windows to cool off and not rely of an AC or heat pump for cooling. They mainly have the active ventilation because you should WANT fresh air - and reasonable way to do that efficiently is with active and constant ventilation using a heat exchanger (HRV or ERV).

[@ccconsulting]

@@retireorbust Wait what, US dont have tilt windows by now? Thought the sliding window was an old movie thing :D

[@FreekHoekstra]

@@ccconsulting sadly no xD

[@williamgrissom9022]

Way back in the 1970's energy-crisis while in engineering school, I pondered ways to retrofit the many concrete-block homes in Florida for efficiency. They have the mass of concrete going for them, if it can be enclosed by insulation. That would allow storing daytime sunlight to stay warm on winter nights, but in much of Florida a well-insulated house hardly needs heating the interior since body heat and utilities give enough heat. In summer, one might run the AC only at night when more efficient (rejecting heat to cooler outside air) to chill the home interior and make it thru the day without AC. But, dehumidification is a bigger AC need in the east. Using thermal storage works better on the West Coast where day to night temperature swings are larger. I retrofit my Atlanta wood-frame house, built in 1929. I had cellulose blown in the exterior wall cavities, which gave R-19 as I recall. When I later tore out the inner plaster-lathe wall in a bathroom, I found the cellulose was packed in very tight to stand on its own. I insulated the ceiling with R-30 fiberglass, a whole-house fan to pull in cool night air in Spring and Fall, and put storm windows over the original wood casement windows. Later replaced the gas floor furnaces with an outdoor packaged gas heat-AC unit, with ducts run in the crawlspace. Utility bills were quite low after all that.

[@kaupaxup]

Can't wait to see the progress on both these homes. Sounds like both your homes are on the southern side of things though - Ever looked into linking up with any other tubers further north where the winter cold is more of a factor than the summer sun? Not everywhere has access to good geothermal and there are lots of places people live where those coldest months don't get much sun to make use of. My wife and I have been collecting ideas for our dream home, but we won't have to worry about summer cooling at all so much as heating and are equally interested in being able to grow a lot of our fresh food inside.

[@StormGod29]

I've also spent years researching and thinking about this problem. Check into seasonal thermal energy storage and specifically Drake Landing in Canada. You store heat collected during the summer in the ground beneath the house and use it all winter long. Likewise with "cold" collected and stored during the winter. The challenge is sizing everything correctly a priori but if you nail it, you can heat and cool all year long for virtually no energy at all. A solar panel can easily manage the pumps needed! Imagine heating and cooling a house for

[@nickns732]

Pretty sure at least his current house is in New England somewhere. He’s talked about cleaning snow off his solar panels in previous videos.

[@kaupaxup]

@@nickns732 New England is not very far north and doesn't deal with much cold of the kind we deal with at higher latitudes. Trying to reach net zero or heat without fuels in minus 30-40 is a whole other beast than a few degrees below freezing.

[@kaupaxup]

@@StormGod29 Thanks Chris, will do!

[@jonathanburr9798]

The biggest impact is getting the low emission parts down - which is what passive house is really good at. Once that's there - the heating system is usually small enough that there are a lot of other approaches that being to make sense. It's common for passive house even in canada for single family homes to go all electric - mostly because you can't find furnaces small enough and the cost between the gas and electricity on such a small amount of heat needed is not a huge concern. Passive house actually has more problems in warmer climates - it's harder to control for overheating from the windows and sun than it is to design some heating into the mix.

[@peterjones6640]

Interesting Matt. I am in the U.K. and started pre Covid on outline plans for a Passive House equivalent standard ( although unlikely to go for accreditation). However Covid and other issues have put the project back considerably. As the new house will be my wife and I retirement home we did not consider retrofitting our current house ( also downsizing) which was built in approx 1850. Our current house was fully refurbished when we bought it some 30 Years ago and I did then put in internal insulation, new efficient condensing boilers, heat reflective glass in the windows, if I was doing it again now I would go much further. So we are going for a new build most likely to be ICF with all the elements you have described ( MVHR, ground source heat pump, PV and batteries) like you the objective will be at least net zero( on running).

[@UndecidedMF]

Sorry that covid set back your plans. Hope you're able to get it going again.

[@tab9920]

Looking forward to more videos on your build. Have been following what Bensonwood has been doing for years. Their custom builds were way out my price range until Unity Homes came along. Love the Zum home plan and hope to build one in the future. Can't wait to see your thoughts on buildinv a home with Unity. Love the channel!

[@87vortex87]

I bought a house from the 1930'ies and did floor, wall and roof insulation. Changed all the windows to HR++ glass, put in underfloor heating, solar panels, and installed home assistant with a whole fleet of smart devices to save energy. Last project, for now, will be to install PVT panels to get rid of the gas heating entirely. That will also be the most expensive project. After that we can buy electric cars and also cut down on the gasoline expenses.

[@danbrophy3785]

I’m excited for you. Unity Homes in near me and has been on my radar for a few years. I have friends that work for Unity and Benson. I’m sure you will be happy with the build. I’m looking forward to your discussions on Unity.

[@stunningsalman]

In Pakistan and Iran, desert coolers are very popular. We have dry weather in the months of April, May and June until the mid of July. These desert coolers are much more efficient than air conditioners, but with a lot less energy consumption. I have 10KW solar panels already installed and will increase them next summer and these panels provide excellent shade for these desert coolers. So if you have hot and dry weather then do try this out.

[@richardgreen7225]

It will be interesting to see/hear a review after a year in the new house ... and then yearly ... as the climate evolves.

[@eliinthewolverinestate6729]

Air tight houses can have moisture problems. It is the number one issue we see in passive houses is moisture issues. Erv needs to suck from problem areas like kitchen, bathrooms, and basements. Also rim joist pockets need breathable insulation. Especially with icf walls and no where for the moisture from the masonry to go. Masonry loves to wick moisture. And how does it dry out in an icf wall? Besides at rim joist pocket. Then thermal breaks around windows. This stops cold and moisture going into wood around windows. It's why you should use mineral wool or spray foam in bays next to windows or doors.

[@shmiggit3]

Hi Matt, I think its great you are going net zero, and that maybe the smart home aspect is required to achieve it, although smart homes means lots of sensors and electronics, which isn't necessarily net positive because of their material requirements. I'd love it if you also share & account for the build into your Net Zero estimates, not just operations - How long does it take for smart blinds / batteries / module hourse / etc. to pay for itself (in terms of CO2 eq.)! Have fun with your project!

[@gracilism]

Solar/ batteries typically need to be replaced before they pay for themselves. ROI for building very efficient homes is pretty terrible. The selling point is they can be extremely comfortable.

[@ZylkaLeftridge]

me and my fiance are also in the design phase of building our dream home. we have the land and are in the same boat as you with when to build and where to put the extra money today that will make sense in the long run! we both agree we want a passive house as we will be deep in the country and may have harsh winters. we learned that building with as few corners as possible gives you the best exterior envelope. if you have any say, try to remove small outcoves and make walls long and flat. easier to seal. also depending on your lot try to design windows and overhangs so you get winter sun that enters the house while summer sun is blocked. In Canada and USA its south facing windows. you can calculate your required angel using your cities latitude :)

[@mikec4204]

I love the idea of a net zero house, but I do t know if an airtight house should be the ideal. After adding extra insulation and getting tighter windows, I notice every article that says how the chemicals that slowly leach out of the things in our house can cause health problems long term.

[@StormGod29]

The house itself is extremely air tight but there is a HRV that does change the air an appropriate number of times per hour. The difference is the HRV can exchange inside air for outside air without losing heat even if there is a temperature differential between inside and outside. No one is building a plastic bag full of VOCs!

[@mikec4204]

@@StormGod29 sounds pretty good!

[@michaelcook9414]

A lot of people harp on about the extra costs, long payback period, green credentials, etc. But the best thing about these types of houses is the instant you step inside one you realise you were missing something you never had - comfort, filtered fresh air, health improvements, less noise pollution, more control, energy independence, even peace of mind... all from day one.

[@OweEyeSea]

Sounds like a fun project. A lot of what I have read on Net Zero homes hyper focus on the energy usage the first year, and ignore the energy that went into the build or remodel, as well as energy for maintenance and replacements over the next 30 years. Some energy efficient systems take more energy to manufacture and may have a shorter life. So I'm wondering if you did a comparison of the entire energy cost for a new build vs retrofit of an existing home. That would make a great video.

[@zack9912000]

i work on these hvac systems daily, and the total cost of ownership of the equipment, repairs and down time is substantially more then any savings of a basic 96% gas furance and 16 seer AC. Its marketing bs on savings in the first 5 years only.

[@UndecidedMF]

I'll be trying to answer some of those questions in future videos.

[@MG-qo5ge]

I've just finished a nearly passive house the air supply system with recuperator but I have also added air heat recovery system ( special buried ductwork) if the temp is -5'C outside the room supply air comes in at 18 to 20 'C with no heat input and a bonus very little dusting to do (as I do the housework a bonus for me)

[@tomsummers1137]

After building / retrofitting a couple homes here in Southern California, reaching or getting close to net zero energy-wise, and then retiring, I’ve decided to go tiny-home and play with boats and other EV modes of mobility. What a trip! Next project? Perhaps a modular net-zero home build halfway around the world, where my son and his family live.

[@Tailspin80]

Sounds like all your CO2 savings will be undone by long haul flight emissions.