Building Energy Efficiency | This Old House

Richard Trethewey checks out an Idea House in development and learns about energy efficiency building techniques.
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Richard Trethewey goes to Devens, MA to visit a new house with advance building techniques. He meets builder Dan Gainsboro who says the entire heating season will only cost $1000 or less for this new house-considerably lower than what our homeowners were paying to heat their house. He shows Richard how the houses in the development are built using 2x6 walls with insulated panel sheathing for a water and air-tight shield. Walls are insulated on the inside and the window openings are wrapped with flashing tape and even the headers are insulated. They used triple glazed windows throughout. The finished Idea House is a lovely small scale home with an open floor plan. The light fixtures use LEDs and the appliances are all Energy Star rated. In the well-insulated basement, there’s no mechanical room because mini-split heat pumps are used to heat and cool the entire house. And finally, Dan shows Richard the solar panels on the south facing roof of the garage. On a sunny day, the panels generate enough electricity to power the house for a family of four.
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This Old House is America’s first and most trusted home improvement show. Each season, we renovate two different historic homes-one step at a time-featuring quality craftsmanship and the latest in modern technology. We demystify home improvement and provide ideas and information so, whether you are doing it yourself or hiring out contractors, you’ll know the right way to do things or the questions to ask. Our experts including general contractor Tom Silva, plumbing and heating expert Richard Trethewey, landscape contractor Jenn Nawada, master carpenter Norm Abram, and host Kevin O’Connor give you the tools you need to protect and preserve your greatest investment-your home.
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Building Energy Efficiency | This Old House
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[@antimatters6283]

This was an interesting but brisk run through. I would love to see a more detailed look at each area, such as the basement insulation and setup, how they handle drainage or water protection in the basement.

[@PaulHenreid]

Structural Insulated Panels, air source heat pump, solar panels, triple pane windows, and mechanical heat recovery - great video!

[@JJ-zg1hh]

Great house. It seems to me that the technology on display here is what will 'win the day' in the long term. Air source heat pump, solar pv, advanced insulation and heat recovery mechanical ventilation. Big capital expenditure but costs peanuts to run.

[@ozzy2753]

I just bought that r sheathing . 70 sheets for 5,500. We’re doing a whole roof for an old a-frame and then cedar shingles over it

[@dougsmith9028]

Oswaldo Rabanal what do you want? A cookie.

[@ozzy2753]

@@dougsmith9028 that would be nice actually. Thank you. However, if someone wanted to know how much the r-sheathing cost. I was just sharing information for the community.

[@augustreil]

@@ozzy2753, Thanks !

[@StariusPrime]

How thick was the foam on the sheets you got, and what was the R value?

[@ozzy2753]

@@StariusPrime the sheets have two inches of foam. R value of 12

[@michaelmcnew744]

Watched This old House show for many years.

[@bigroblee]

Thank you for sharing.

[@warnerrobins8542]

Wow, that is exciting.

[@gus473]

Bob Vila signed my toolbox! 👍🏼😎✌🏼

[@donaldlee6760]

I really like the smart choices the builder did, reminds me of the Joe Lstiburek building philosophy. Only criticism is the bottom mounted vent hood on the induction stove.

[@andreycham4797]

Lstiburek is an educated dude . This one doesn't know what he is doing . He builds walls in Massachusetts like he is in Florida or Texas . He installs mini splits which is smart but what for he spend lots of money on basement

[@Natedoc808]

Downdraft range pulls warm air into the heat exchanger so you aren’t venting to outside the conditioned envelope. Standard good night as well be an open window in your roof.

[@aaronvallejo8220]

This is how we build our clean, highly insulated and renewably powered future.

[@Natedoc808]

Nothing renewable about synthetic materials and foam. Hemp Crete has better R value, so does straw bales.

[@kingssman2]

Looks amazing. For just 1,900 sq.ft, I wonder what a new construction like that would cost?

[@jimdevilbiss9125]

Really great use of technology. Except is the most developments one house is almost on top of the other.

[@bosse641]

Lovely home.

[@afrafathi9316]

This is amazing

[@williamreeder3660]

Brilliant !

[@leozmaxwelljilliumz3360]

That house is probably 400 to 500k. Super efficient but very expensive to build. I do like what they did but I'm curious about the insulated header load strength

[@bruceclark7198]

Don't forget, the owner will save thousands every winter!

[@Natedoc808]

The insulated header doesn’t make much sense seeing as there is a Thermal break via the ZipR foam insulated backing. Wood has a decent R value of R 1.25/in of thickness so a 6x header has an R value of 6.875 plus the foam insulated backing pulse the sheathing. Silly to cough up structural strength and add the cost

[@deerhunter7482]

Probably closer to a million.

[@scotteric8711]

The methods and style of HVAC units have been in Europe for almost 50 years.

[@jblyon2]

I'd still want a gas furnace and water heater there (or a gas water heater with a heat loop off it). The electric rates are sky high, especially in the winter, and only get higher every year. I don't care how efficient it is, if you're paying 22-24 cents/kWh running a heat pump is going to be expensive.

[@augustreil]

Would the solar panels help with that ?

[@jblyon2]

@@augustreil They would, but output from solar in New England during the winter is way less than the rated output. That array might put out half as much power as the heat pump draws on the average day.

[@brettlaplante6180]

@@jblyon2 is net metering in effect in New England area?

[@jblyon2]

@@brettlaplante6180 Yes, but there's a million hoops and a mile of red tape to get through with the utility. That 5kW array might put out 2.5kW on the average winter day, and that heat pump should be drawing 5kW while running. Add in the water heater, dryer, stove, and other electric use and it's not going to keep up, even on average. What sucks is most solar incentive programs only cover your average usage based on the peak output potential of the array, so around here you're left with something that can barely meet half your needs for half the year.

[@emmett3067]

Electricity costs in many parts of the world are double 22-24 cents /kWh.

[@BryceFromNowhere0547]

That's nice

[@Marcel_Germann]

Yes, it is nice ;-) kzbin.info/www/bejne/aYikgKuBhNKFb5I

[@saulgoodman2018]

Spend $50,000, to save maybe $2,000 a year. Which would take 25 to break even. Which by then, you will need to spend like 25k on a new HVAC system.

[@knockitofff]

zero chance that those ductless units last that long

[@michaeld2613]

Nailed it.

[@GreenAppelPie]

Great use of space, but yeah it looked a bit cramped.

[@803mastiff9]

Light and Tight.

[@saulgoodman2018]

That's what she said.

[@loueckert4970]

What did all of this COST and how long to PAY BACK the savings? Is this construction worth the cost? Great video, thanks!

[@Chrisisreal978]

Solar panel arrays of this size in Massachusetts have an estimated payback period of 6-7 years. The rest of the house is maybe 10-15 years to recoup the cost compared to minimum code. Net savings over 50 years could be $70,000+ based on their $1 v. $3k annual heating cost. Supposedly building comfort is pretty high in these net-zero houses too.

[@marcob1729]

@@Chrisisreal978 how can anyone think of net savings over 50 years? I'll be in a nursing home by then. Only 37% of Americans live in a home for more than 10 years. You're better off thinking of retained value, which is complicated. As another commenter said, all these things are awesome until you're the one stuck replacing it

[@michaeld2613]

You likely won’t stay in one place long enough to recoup that sort of outlay.

[@FreekHoekstra]

@@michaeld2613 it also adds to the sale price so it’s not money down the drain even if you move. Plus don’t forget about the increased comfort. In general building air tight with great insulation it only adds about 2 to 3% of the total home construction cost as per BCIT‘s research. Solar panels and the more efficient heating and cooling system add a bit more, but by building more efficient you can actually downsize your heat pump/AC unit quite significantly which then ends up saving you money again. Ultimately 2 to 3% extra is where it tends to roughly stay which is not bad for the additional comfort that you get and the additional savings you get every month. And again if you do sell you will get that money back when you sell.

[@genkiferal7178]

@@FreekHoekstra and probably adds to your property tax bill as well, then - if locals know you built in a special way - and the local inspector probably tells the assessor when they meet in the break room

[@tomnelson7697]

Great for new homes but what do I do with my foundation that dates back to 1920? I want to pull away the soil to seal coat the foundation or check if it's already been done. I also want to depressurize the house with a home energy audit but my walls need to be insulated as well. I have a long list but finances are tight.

[@rupe53]

Tom ... if you are willing to do most of the work yourself and stay long enough in one place you can make a serious dent in the repairs over say the next 10 years. I figure it ran me a bit over $20k to do it that way.... one room at a time. Started with a 1910 home that was fairly drafty at 65 degrees all winter and now it's 5 zones of heat at 70 degrees for half the cost annually. The main difference is the comfort level without the drafts. Oh, add in another $5k because each room got updated with insulation, electric, and the top 2 floors didn't actually have heat in the 1910 build. (heat rose from the first floor) It wasn't in the budget originally but I left room for AC which was added in recent years... another $3,500 in parts that I installed myself. Yes, I refinanced along the way but I wound up with a new home inside the old shell.

[@marcob1729]

@@rupe53 I have a concrete block house built in 1979, and it needs some serious upgrading. The problem is that I paid for 5 year old stucco and roofing that were both done poorly. It's going to be interesting for sure

[@samash1704]

Almost said "livin large'.

[@Matt-dc8lp]

It's like a Matt Risinger for beginners show

[@maknotv]

Price of the house?

[@joshuajackett6371]

The build cost here would be massive.

[@keithmiller1982]

Where exactly in Devens is this? I spent about a year living in one of the barracks on McCarthur Ave near the Ft. Devens Museum.

[@keithmiller1982]

Found it.

[@marcob1729]

I grew up right outside Devens. When I moved back home for a bit, it was really surreal to go to the gym in the new "town"!

[@edwardlouie]

What about all the nail heads to secure the ZIP-R sheathing, how do you waterproof those nail heads?

[@toedplays]

Zip sells a liquid product to seal those. They are sell-and suggest-using their stretch tape for openings

[@matthewlewis5631]

My thoughts exactly. Zip stretch tape and liquid flashing. Why mix brands like that?

[@edwardlouie]

@@matthewlewis5631 I've seen the zip 2.0 videos where one goes back after the zip sheathing has been nailed to apply fluid applied flashing over every nail head. Taping every nail head doesnt seem that much faster. Tape or fluid applied, both just seems like a slow and labor intensive process. I was just wondering if there was a faster way.

[@Robert-ex2qp]

Does anyone here know when the first episode of This Old House was?

[@gus473]

Bob Vila just returned from World War I, as I recall. So around 1919.... ¯\(°_o)/¯

[@chaseweeks2708]

All that Zip R12, but couldn't spring for a bit of Zip Stretch Tape for the window sills? That 3M stuff isn't going to last long the way they had it cut.

[@scallywag1716]

Oh I love me an airtight box....

[@saulgoodman2018]

That's what she said.

[@augustreil]

@@saulgoodman2018, ''HE''

[@saulgoodman2018]

@@augustreil And she. There are women who loves boxes too.

[@augustreil]

@@saulgoodman2018, Ha, true.

[@RicardoJunqueira]

Isn't this episode a re-upload? I think I already saw this segment before.

[@TerminalSaint]

Definitely.

[@maureenburian2185]

Why are use fiberglass why didn’t you use rock wool It’s fireproof and it also lasts longer fiberglass just shrivels up and shrinks

[@rafflesmaos]

Hmm, isn't a multisplit in such an energy efficient house going to cycle a lot? Especially with very low per room heating/cooling demands? Would have thought that a ducted minisplit would have been better when the loads are very low.

[@Chrisisreal978]

Those newer units have inverters and run the pump motor at variable speeds to meet the load instead of just cycling on and off. It's more efficient and I think you get a more consistent temperature.

[@rafflesmaos]

@@Chrisisreal978 Well yes, they are variable unlike something like a single speed furnace, but I'm more referring to the minimum capacity of the outdoor compressor. For a cooling example, if one takes the MXZ-4C36NAHZ2, a 36k BTU unit, the minimum cooling possible seems to be 15.5k BTU. So say that only one indoor head is operating, I would think that it'd still cycle constantly. Wouldn't one need all of the indoor heads operating and have the combined load be more than the minimum ratings in order to avoid cycling?

[@brettlaplante6180]

@@rafflesmaos or allow a greater range between Tmin and Tmax internal to the house.

[@Chrisisreal978]

@@rafflesmaos Oh maybe you're right. I didn't realize that the minimum loads were so high. I guess it could cycle on and off if just one head unit is running. Not sure that's necessarily bad for the unit except maybe it won't pull out enough humidity during summer? Massachusetts isn't a particularly humid climate so it might not be that big of a deal in this specific case?

[@rafflesmaos]

@@Chrisisreal978 Yeah, I guess it would depend on how well the Manual J was calculated. It's both a small and energy efficient house, plus installers in particular tend to oversize units to be on the conservative side. As you've said this can get weird/complicated for humidity removal purposes too. Passive houses in particular (which this isn't but still might) suffer a lot from that, because in air tight construction one may also worry about indoor humidity not just one that is incoming from outdoors.. plus the latter should be mostly balanced with the ERV. Edit: Note that this humidity removal concern is not a /bad/ thing about airtight/passive houses, just something that needs to be kept in mind. It's still a very minor thing compared to the massive benefits that these types of constructions bring to the table.

[@rextundra2239]

So....Heat Pump moves heat into the house. Water heater moves heat from inside the house in to the water heater. Do they make a water heat pump that moves heat from out doors into the water heater?

[@augustreil]

I believe they do.

[@bnasty267]

They do make split heat pump water heaters, but the cost probably wouldn't be worth it. Those basic heat pump models are around $1000 and the cheapest I've seen the split water heaters are at least double that. You wouldn't save enough to pay it back over 10-15 years. Sure, you're stealing some heat from the mini splits to heat water, but it's still way more efficient than straight electric.

[@jimg8218]

Is it affordable housing

[@writingpanda]

Lol no, not at all.

[@rupe53]

Never quite understood the economy of a heat pump water heater. The air it steals the heat from is within the house so all winter you are using heated air that you already paid to heat, which is probably less efficient because of the double transfer. It also uses electricity rather than say propane or natural gas, which usually has a lower cost per BTU. Yeah, it might be cheaper to run than a full electric water heater but there's more ways to skin a cat than doing it all with a heat pump. This style of water heater will also pull KWs from your solar system, which might be used better elsewhere.

[@wzDH106]

Understood for basement, interior heat pump installations. But even so, manufacturers offer ducting options to avoid this issue, similar ducting to a well installed gas water heater. We have our heat pump tank in the garage, a welcome addition for humid summer days while also taking advantage of any garage waste heat generated from vehicle charging, chest freezer and our heat pump dryer. They mentioned a 5 kW solar system. I'm not sure if their model is schedule programmable to take advantage of solar generation, they will most likely tap into the grid when household demand rises at sunset. Either case, 5 kW during daylight is more than enough to cover the basics.

[@GreenAppelPie]

Even though my basement floor has partial 6” walls, the builders only used 4” insulation. Why you ask. Because by code that’s all they had to install.

[@FreekHoekstra]

Wow thats just sad xD

[@artfuldodger978]

That should be the standard for houses in this country.

[@kirill__kirill]

Влагонакопления не будет в минвате, если дом снаружи обшит слоем эппс? Странное решение у немцев в этом плане

[@shameemnoohumohammed9527]

Good but don’t ask about the cost

[@thewarwithin4776]

wonderful house, if you have the wallet ..

[@BobBob-we3wr]

I wonder what the upkeep would cost and I be concerned over a heat pump. I guess if it doesnt get too cold your fine. I imagine 5 F is in perfect conditions. I used to have a heat pump and it struggled when ever it was below or near freezing. Insulation probably helps.

[@maknotv]

On a 2 or 5 thousand dollars savings a year

[@marcob1729]

No one can tell me, how long are those tapes supposed to last? Zip tape, 3M, etc. I've never met a tape that didn't dry and crack with age.

[@4TwentyFour20]

its not exposed to sunlight so it should last quite a long time

[@jakesarms8996]

You'll have to be wealthy in Illinois to build that. The property taxes cancel out anything you save. I'd rather give the money to the utility company than the State.

[@Wasabi9111]

My 1950s house is so drafty and freezing. No one can seem to be able to identify the source(s) of cold air. It’s so bad that I’m planning to sell the house and move other a better insulated house. When buying a house, how can one determine whether it’s well insulation?

[@tonycraft380]

Blower test

[@palillo2006]

During the winter rent a FLIR camera to see where the draft is coming from.

[@rupe53]

wasabi9111 ... you probably can't tell if it's well insulated unless you are willing to crawl around and do half of a building inspection. OTOH, you can look at general construction, stick your head into the attic and look around, try some doors / windows for fit & sashes rattling. Also check the feel of how doors open and close. If these small things are shabby then the house is likely drafty, which is the other half of energy efficiency.... but usually easy / cheap to fix compared to reinsulating the whole place.

[@shawnd567]

$1000 for the heating season is impressive? I'm near St. Paul MN and my cost for the heating season is under $500 for 2200 sq ft.

[@hmbpnz]

Yeah I don't get it. Our house is a 1920s poorly insulated home in Chicago and we don't spend NEARLY $1,000 all winter!

[@desaltzman8762]

What energy is used for heating? Gas, electric, oil....

[@rupe53]

@@desaltzman8762 ... heat pumps here are all electric.

[@shawnd567]

@@desaltzman8762 Natural gas. My estimated cost with heat pumps would probably bring me near that $1000 seasonal cost but it's not a "passive" home. R20 walls, R60 attic. R25+ basement walls. It's well insulated but no thermal break for the studs. I would have expected a truly properpassive home, similar sized, in a warmer climate to use far less energy than I do.

[@wantapgt]

I love a good tight box

[@cbryantbear6498]

They never say a cost for a house like that...

[@rupe53]

cbryantbear ... in other episodes they discuss the costs indirectly by saying it raises things by 20 - 50 bucks per square ft over conventional minimum code. IOW, on a 2k sq ft home that's $40 - $100k more up front.... but there are still tax breaks on certain energy star appliances and solar installations. In most cases you save in the long run after 10+ years.

[@danielq.4371]

@@rupe53 good to know. Thanks for the info.

[@genkiferal7178]

@@rupe53 My understanding is that appliances can also be factored into your property tax assessment

[@rupe53]

@@genkiferal7178 .... yes, most permanently installed appliances will be factored into assessed value of the house... and therefore into taxes. This is one of the major reasons people add above ground pools or hot tubs instead of sinking them into the ground. The adjoining slab or deck is "structure" so taxed, but the pool or hot tub is free standing, so exempt. OTOH, I don't think I have ever seen one of these qualifying for an energy star rating.

[@genkiferal7178]

@@rupe53 I've seen some Japanese kitchens with kitchen furniture on locking wheels that fits under permanent, fixed countertops. For tax reasons, things like that and armoires might be a good idea - though they waste a bit more space - maybe as much as 25% wasted space, I think, compared to built-ins. They don't look quite as good, either.

[@adrianmcnally6006]

Hope this is affordable so more people can jump on it, the earth needs it!

[@scottwebber652]

R the insulated headers code / strong enough ? Seems u lost structure keeping them apart.

[@rupe53]

Scott ... it's still a pair of 2-bys but with a thermal break. How much do you really need?

[@BigLazyMexican]

Question is longevity and will this work in southern climates as well?

[@MariuszChr]

Under 1000 per season for heating is low? Where it was? Alaska? Seems high. And whole thing probably costs over 1M in average neighborhood

[@xBRVTALx]

Why would you spend the money on zip sheathing and then cut corners (literally and figuratively) by not using their stretch tape at the window sills? Instead they use some 3M tape and cut it at the corners, potentially rendering the zip waterproofing less effective.

[@mrlibowski493]

Felt like I was supposed to not giggle every time he said tight box.....

[@vladimirkozyan8658]

I still don’t see the shear power of the zip r sheathing. That foam doesn’t provide shear and having nails going through. It just provides place where nails would bend at strong winds. Best to shear the wall with regular osb and then use zip r... it just my thought

[@youredoingitwrong1361]

Plumbers happy with the solar, it's gotta be good

[@parkerk7018]

Why do they have Richard cause he’s no cawhpentah WHERES ole Tommy boo M.I.A

[@EmailgroupieESLEducation]

Wow if my dad were alive he would be screaming. He built the addition to our family house with all these products. They were new age 15 years ago. Great video

[@EmailgroupieESLEducation]

And in the basement we had the aluminum sheeting and the new owners didnt want it. Lmaooo dumb asses. They will pay rediculous amounts in heating. 5 car garage with basement.

[@johnsavage8873]

Go 3d and some energy and money! Stick built is obsolete because less people can afford it!

[@julianreverse]

Why the fck are they insulating the basement from the inside? 🤦🏽‍♂️

[@haroldmccarthy8382]

I like the impregnates part!😏

[@loganperry1346]

That sistem is basically minimum code requirements in Ontario Canada

[@jennyshomo8932]

I live in an old log home that has no log exposed. It has 4 bedrooms and is a two story house I can heat with no more then 3 tons of hard coal a year wichcosys me about $650.00 Next year I will be using a different coal that will cost me no more then $450.00 to heat our home in Pennsylvania for a winter. It could be even less. But because of these Climate change fanatics they probably will be taking my heating source from me.

[@saulgoodman2018]

Because the project house was using an old inefficient system, with no insulation.

[@Mihogan]

What was Richard talking about, $1k being 1/3 of a winter month?? My house is an old 70's home with little insulation, and we keep it at 74 in the winter with freaking OIL, and I pay $1700 for the winter!

[@Mihogan]

and that's with a 70's boiler, original... not sure why this apparently efficient modern home costs around what I am paying on mine!

[@nelsonsilva7572]

He must have a huge house

[@knockitofff]

LOL state of the art and you go with ductless crap???

[@casperunnerup]

Too bad they did used that 3M tape that they had to cut instead of stretch tape. That's most likely going to leak..

[@tommilaine2693]

A small rip in that airtight barrier and you probably have a house full of mold in 10 years...a house needs to breathe.

[@GrahamDIY]

Why are you guys still building houses from trees? Bricks, 100mm insulation filled cavity and thermal blocks on the inside. Lovely and toasty. And solid. And Mr Wolf won’t blow down the piggy house when he huffs and puffs 🙃

[@OutNAboutWithBrad]

Because Americans love cheap and few are able to see long term benefits. It's the disposable society.

[@4TwentyFour20]

wood is easly to source and in earthquake country stone/brick houses fall apart

[@GrahamDIY]

@@4TwentyFour20 the whole of America is not “earthquake country” and they still build homes from brick even in California. They just have more strict building requirements. In frontier times using wood was the obvious choice. Hell, we did it here (🇬🇧) for centuries. But then we began manufacturing bricks en mass Anyway, my comment was tongue in cheek. I really like a New England wooden house. I’d just make sure it was well insulated 👍

[@4TwentyFour20]

@@GrahamDIY all good dude cheers from the usa 👍🍻

[@GrahamDIY]

@@4TwentyFour20 I love the USA. Amazing country 🥰

[@mvboynton]

How in the world is it costing you $3,000 to heat that old house for one month and $1,000 for a while year isn't anything special. House built in 70's, 80's and 90's (3,000 SQ FT) in Montana only cost about $100 a month to heat in the winter months, ......and Contractors haven't used 2x4 outside walls in a long, long time

[@AlphaLibre9]

It'll save you $2,000 but it'll cost you 2 times more for the house.

[@OutNAboutWithBrad]

What car do you drive? ..........You know you could have bought a cheaper car. A high performance house is more than just what it saves on your heating and cooling bill.

[@jacobb6313]

This have could have been an hour long video to explain the reason and why they are better, but they missed the opportunity to show how bad old techniques are.