Hydronic Floor Heating System Review - 2 Winters Later

I've been living with a in slab hydronic floor heating system for two winters now. In this video, we look at how the system works, what I like and dislike about the system, as well as the difference between in slab hydronic floor heating and in screed hydronic floor heating.
Thank you to Scott from Mercury Heating for lending me the thermal imaging camera.
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[@charleyli9363]

Thanks for stopping by 😄, leave a comment and let me know what you thought about the video.

[@darroncrick9993]

Hi Charley, We are currently doing a build with inslab hydronics in Ballarat. We have approached it differently. We are using a solar powered reverse cycle system with a 500lt buffer tank to both heat and cool the slab. We want as much thermal mass as possible so we have insulated the entire slab from the ground on 75mm styrofoam. We have imported everything from China where the systems are in wide use and the total cost is about 1/4 of local suppliers. For such an inherently simple system it is appalling how expensive it is in Australia. It stops people from considering a super efficient green alternative. A properly insulated slab is a fantastic climate control asset and costs little more than a bog standard hunk of concrete.

[@lyubomirkopanov6595]

Its first time I hear about in slab system... in Europe we do it in screen only. The issue with uneven temperature in rooms is easily resolved by installing thermostats in every room which control each circuit individually by motor valve located where the manifold is. Indeed the water heating system is the best!

[@Tigerratcat]

@@darroncrick9993 could you say the name of this system. And would you say it’s a ridiculous idea to have reverse cycle hydronic in slab in qld?

[@darroncrick9993]

@@Tigerratcat we put our system together ourselves. If you look at my youtube videos you will see that our system is a combination of solar tubes, heat pump and buffer tank. Our experience is that the solar system is surprising successful, the buffer tank works but could be bigger, and the heat pump works perfectly. I don't think that the floor cooling would be effective in Qld. It is cheap to run and works well in cooler Ballarat but in Qld it would struggle to get enough "cool out" and you would end up with wet floors. The solar tubes with buffer tank would work perfect and I doubt you would need to boost the temp like we do. I think if you had half our tubes and 1,000lt buffer (instead our 500lt) you would not need to pay for any energy at all. You should be able to install everything for under $10,000. Then just put on some cheapy nat gas booster if required. I doubt you would need it. The feel of floor heating is great, we love it. The problem is that it is slow moving so if you get a warm day you need to open windows to get heat out. It is no problem because the heat is free so you are not losing anything. You will definitely need to cover the tubes in Spring and Summer to reduce the heat unless you have a different use for the heat like a pond or hot tub or something. We have ours running through a domestic hot water coil. Ours is far too small and not very effective. I would be happy to pass on our suppliers and any other thoughts so if you were interested just contact me direct at [e-mail]. Good luck with your project!

[@quintonsweeney8025]

I do this as a profession and love the video. if you find certain rooms cooler due to less piping surface area (bathrooms) try using balancing valves this can restrict flow on your larger areas and open up flow where you have less piping.

[@joshuasmith1215]

That makes too much sense.

[@randybettis76]

Hi Charley, the negatives you mentioned can be almost completely resolved by zoning. So many houses only have 1 or 2 thermostats. Unless your house is tiny this makes no sense. Adding more zones is easily done if the contractor does the proper preparation. One of the biggest mistakes I see is combining the master bath and master bedroom. Never have I wanted to sleep in a warm room and never have I wanted to shower in a cold room. These should always be separated at the very minimum. I can make an argument for every room being its own zone. Then you get people complaining about the added cost. On the whole the cost to add more zones is less than 5% of the total cost of the installation. In my opinion that is well worth the increase in comfort.

[@serviceroad4178]

That is just rubbish. Just heat the entire home equally and save unnecessary complexities and installation costs. If a room is inside the thermal envelope of the building zoning will not save anything energy use wise.

[@randybettis76]

@@serviceroad4178 Clearly you don't understand design and load variations. The people I design for are looking for the absolute best. not just an average system. If you want average just install forced air.

[@extraart1]

Getting ready to build my own house in two years. This is one of the best hydronic floor system videos I've been able to find. Thanks Charley

[@stephenvincent4706]

Great video Charley. Wonderful to see this system being reviewed from an Australian perspective. We are so far behind the rest of the world in things like this. Too many people think that Australian homes don’t need such systems which is why so much money is wasted on electric space heating.

[@Ramdodge582]

A poorly designed hydronic system is the reason for your discomfort with the room/floor temperature. Under slab insulation and perimeter insulation is code in my area.

[@ThiruSiva]

Excellent video explaining all benefits of hydronic. If you can just include a monthly bill for heating your water will sum it up nicely.

[@calmeilles]

The small room problem, and to an extent some of the other cold spot issues, suggest loops that are too long and possibly relying on a single thermostat for a whole house. Make the loops shorter, per room even. Add a thermostat control per room too and you have the required control to have warm bathrooms without overheating everywhere else.

[@Ernescme]

So, as others already commented, the problems you listed can be solved with properly designing the heating system - under-slab heat insulation, uniform slab thickness, consistent depth of piping in the slab, loop length an flow adjustment, zoning etc. Good that you basically pointed potential mistakes when building such heating system.

[@serviceroad4178]

Lots of talk in the comments about zoning etc but that isn’t going to save running costs in any way. As long as every heated room is inside the thermal envelope of the building it will make little difference regarding heating costs. Foam waffle pod systems are used often nowadays and is built in floor insulation. Even that doesn’t really matter because the majority of the floor area is inside the thermal envelope. Edge beam insulation is cheap and an easy thing to install. You should lower your boiler supply temperature to 40c. It will run longer but will save you money. And also will create more condensing time of your Immergas boiler. You want your boiler to condense as much as possible. It’s much more efficient. Your boiler was running too hot from the plume it was producing. You can also increase the manifold flow rates to the cooler areas and reduce flow rates to the warmer areas. Great video. Lots of uneducated comments got me going. Regards, Shannon. GV Hydronic Heating (Vic).

[@riffswamp]

Super informative! One of the best discussions I've found on hydronic floor heating pros and cons + areas of potential improvement! Thanks for sharing!!

[@charleyli9363]

Cheers Jon, learning together 😎 thanks for watching.

[@capitol699]

I stumbled upon your video by accident. I have to say you did a first rate job. I work for a builder of eco-friendly homes in Virginia (US). I am now going to talk to my partner, (the concrete guy) about the screed idea. Thanks again for your information.

[@charleyli9363]

Hey Joe! Thanks for watching. I think the screed is definitely the way to go from a building science and life cycle cost perspective. It is significantly more expensive as an upfront cost, but should be a good value proposition for many projects.

[@tabitharoyer9629]

Hey Joe K, do you mind if I ask what builder you work for? :) I'm also in VA and looking into hydronic floor heating.

[@capitol699]

@@tabitharoyer9629 SK eco builders. What part of the state are you in? Are you building from scratch?

[@tabitharoyer9629]

@@capitol699 Thanks for sharing! I'm in Hampton Roads. No, unfortunately not building from scratch, so I guess maybe it doesn't really help to ask for the name of a complete home builder... I just thought it was nice to hear of a builder in our state using this kind of heating! Trying to figure out where to start in looking for the parts, etc.!

[@capitol699]

@@tabitharoyer9629 email me at [e-mail]. I can send you some companies that offer kits and parts. Pretty straightforward stuff. You will need a plumber and an electrician unless you posses those skills.

[@kh2226]

Hi Charley, Thanks for this very informative video. Very clear and easy to understand. It's hard to find information for alternatives to the dreaded air conditioner. I'd love to consider in-screed heating for our duplex which is now around 20 years old. It has a concrete slab. Two storey with insulated roof cavity. I'd only put the hydronic heating on the ground floor living areas. The upper floor is fully carpeted and fine in winter. In the bathrooms I wear slippers until the shower is hot so don't need it there. I hate air conditioning, plus I'm very hard of hearing with tinnitus so any small background noise adding to other background noise makes hearing over tinnitus more difficult. I only use air conditioning in my car when I have a passenger because it makes me feel suffocated. So adding an air conditioner to my home would pretty much mean constant misery for me and divorce thereafter. Questions I have are regarding technical matters not mentioned. It would be great if you could follow this video up with one regarding the space the manifold and any other components take up. I can't really tell the size of yours in the close up (I'm assuming mine would be smaller for smaller size duplex). If the booster is electric how much room would that take up, assuming it's separate to the fuse box (I'd consider installing solar PV eventually) and any other outside components such as the pipe expelling steam (this duplex has very little space outside for these things, eg nowhere to put even a slimline water tank). Our single garage but is crammed full of partner's tools and toys. Also, whether the outside components are noisy. I'd be interested to know whether your system is still working fine 3 years down the track and how much maintenance is needed. Also, I'd like some idea of how much depth is needed for the screed + insulation + hydronic pipes. Our ceiling is a lower 00s style of around 2.3m height. I need to consider whether it would feel suffocating if anything more than around 10cm was added to the floor height. This may be outside your experience. Perhaps someone else might know. I find it very difficult to get proper technical information from professionals at any time, particularly not being able to hear them, and without partner's support makes it even more difficult. Again, excellent video. Thank you.

[@neckofthewoods24]

Your complaints are just because of how it was done, not the system itself. Tubes could have been laid differently and insulation could have been used. That’d fix the 2 main issues.

[@cmss29]

@charleyli9363 In my area of the US, underfloor 2" 4'x8' foam insulation board (Owens Corning Foamular 2" is what I used) is required under the rebar mat and pex tubing. I believe this is the standard in most areas of the United States (Maybe Austrailia too?). Also, I another perimeter foam insulation is required at the exterior edges of building. I think this is a major positive in reducing heat loss, which you did address in your video. My point is it does now seem to be a building code requirement which is good for the homeowners pocketbook and for the environment.

[@benburgs5423]

Great work on a detailed review post install and usage, have you seen the electric ones used in tile glue? Cheap but gather would be expensive to run...more for renovation that new build

[@charleyli9363]

Hey mate, yes I have used that system too. Very cost effective for bathrooms, and very comfortable. Only need it to run for a couple hours morning and night for most peoples. It’s also very easy to install and doesn’t require complex integration with other trades and what not. It is less efficient than gas hydronic though and the thermal mass of a 10mm tile doesn’t hold much heat!

[@yolo_burrito]

You could also change the boiler out in the future with an air or ground source heat pump.

[@joshuastull725]

You may want to include the radiant heat transfer from an infloor system, as opposed to convection like you describe. Heat loss from the body is highest through radiation and matching that with this type of system is the reason why it is so comfortable. And that wasn't as cringey as you may have thought:)

[@serviceroad4178]

Congratulations. Probably the most educated connect so far. 👍🏼

[@raviandsandhyaprakash7744]

How do these systems stack up now with new builds in Vic not allowed to have gas connections? Do electric heat pumps pose any problems? 50deg C would be close to their max temp output I'm guessing.

[@johannbeckham]

Which engineered wood that's available here in Australia can work well if hydronic floor heating? I love the idea of hydronic floor heating but I don't like the look of a polished concrete?

[@johnzach2057]

Insulate insulate insulate. Get to passive house standards and then a small 12000 btu mini split is more than enough for most houses in warm climates.

[@quengo3284]

Can you tell us about the hydronic heating system maintenance in details please.

[@co2588]

Not sure we'll be able to have gas boilers any more. The gov is banning gas... Anyhow, we're country,Vic, we only have bottled gas... so back to solar i think. Great video, very informative. Thank you

[@eklectiktoni]

Just for clarification, your house is only heated with the radiant flooring, correct? I've heard some sources say that you may need a backup heating system, but maybe that's only in really cold climates?

[@kathyadkins3136]

Most ppl insulate under the pippin to keep the heat above and not below the ground.

[@ZylkaLeftridge]

How did you finish the concrete floors? I'm in the early stages of design and have planned to install hydro heated concrete floors, but debating on covering with tile or just polished or epoxy coated? Any advice?

[@tommysanfilippo3165]

I’m doing mine next week and it’s going to be acid stained.

[@chrischan001]

Hi Charley, awesome video on hydronic floor heating. I am engaging an architect to draft the plan for a house I hope to build next year. Just want to know how much you pay for gas in the winter season and what is the floor size that you are heating?

[@arji66]

following. I was coping 400 dollar a month gas bills in winter with hydronic panel system, 4 bedroom house.

[@chrischan001]

@@arji66 Thanks. According to the Facebook group My Efficient Electric Home with 30,000 members, if you decide to go hydronics, heat pump is a much more efficient technology. Go check it out! facebook.com/groups/MyEfficientElectricHome

[@gabriellegb6922]

Love this video, so informative! I'll be building an in-slab hydronic heating system, but will be insulating the sides and bottom of the 4" slab. I'll try to think about zoning and layout through smaller rooms! One question I have is what did you use to finish your concrete? I love the look of your floors and I'm looking for a good sealer!

[@charleyli9363]

Hi Gabrielle, thanks! Concrete is a nil exposure burnished finish polished to 400 grit and sealed with a penetrable sealer. Nil exposure is tricky because the slab needs to be poured really well with no significant undulations over short distances. With higher levels of aggregate exposure, the grinding helps flatted and level out undulations- but we do not have this luxury with nil exposure. The other thing is that the slab needs to be burnished during the pour. This process essentially requires the Concreter to continuously trowel the slab for much longer after the pour in order to really compact the finish. As the floor is “less hard” with lower levels of exposure, it is generally recommended that you use 32MPA concrete and extra reinforcement. I would also think about running expansion joins/cuts under wall plates and potentially through the visible sections where needed to mitigate cracking. This is why it’s really important to get the slab engineered for nil exposure burnished concrete as well as your in slab heating, in consultation with all contractors and designers. These factors will all contribute to the performance of the floor. The penetrable sealer is meant to go into the pores of the concrete and provide protection - all without changing the texture, sheen and general look of the floor. This is what I’d go for instead of a en epoxy sealant for instance. I did make a polished concrete video a while back on IG - here is the link: instagram.com/tv/Bvs_3j1F-lD/?igshid=178reitrznzkl

[@aaroncottrill7426]

Cant u just insulate under the structure concrete?

[@peterbeyer5755]

Pre heat the water with. DC element attached to PV. This is done in the US and reduces the cost of running the system.

[@charleyli9363]

That sounds like a good idea, especially as it doesn't take much energy to keep the system running once its up to temp.

[@slanyt]

Is this the same as those radiator Panels that are attached to the wall?

[@celyl]

You're down under. How cold does it get there?

[@jessiewan5401]

Is it same as radiant heat?

[@kshred3043]

If you go in-screed you loose thermal mass. Relative to in-slab, this would work against the economics of running an air-to-water heat pump only during the night, on the less expensive, 'night rate', electricity tariff and making it last during most if not all the day. Of course, this consideration only applies to countries in which heat pumps are the heat source of choice and night rate tariffs are available. Furthermore, all things being equal, it would seem that when the pipes are closer to the surface they need to be spaced closer together, ie: because there is not enough diffusion to even out the heat to the extent obtainable by deeper pipes.

[@cocoioo]

can this system heating up 2nd floor?

[@Negaah21]

Radiotor for 2nd floor could be less complicated.

[@elischultes6587]

Sometimes they put thin concrete on top of the wood subfloor. They can run loops in joist bays with insulation forcing heat up. Like what he describes the inscreed heating system.

[@randyanderson1983]

Icf slab house with radiant heat floor with foam boards under concrete closed cell spray foam roof fixed all those issues “boom drop the mic”

[@greasezert2228]

I know a man that has this and he wishes he had not done it. The major drawback is once you have the concrete warm and you get a mild or warmish day you burn up. Works great if the outside temperature is cold and stays cold.

[@ralphlumbard6493]

Unfortunately for you, your contractor that installed your in floor heating system did it incorrectly. I have not cool spots. I have it in my showers. In Screed system in my house 10 years old.

[@bpdp379]

When he said can’t install in shower I almost choked! It’s one of the main spots to install it IMO.

[@TheKonnoisseur11]

Why can’t you put it in your bathroom ?

[@hvacdesignsolutions]

Sounds like the installer messed up. All those problems are down to poor planning and design.

[@MrBill99]

Other practical disadvantages of hydronic from personal experience is stale air and VERY slow heating. Stale air can be improved by cracking a window or adding a ventilation. But they don't respond quickly to dropping temps.

[@grheryford]

Add an ERV to solve for the stale air.

[@plumbbuildrenovate]

same goes for insulation... again poor installation.

[@028guicho]

If it were my home I would have used Copper pipe... & the reason for that is it never rust & evenly distributes heat & cold. Yes it' pricey but remember it is in investment

[@shaeff865]

Concrete eats copper, so I'd advise against that. His issues aren't due to spacing of the piping, his issues are largely based off the fact that the system wasn't built correctly. (no insulation under the slab) Contrary to popular belief, heat doesn't just "go up." It goes to where it's cold. He's losing massive amounts of heat out of the edges and bottom of his slab if they're not insulated. He also needed proper zoning.

[@biotechdanc]

we had copper lines in our houses (9) floors, lasted 30 years, then all went within a few years. Loved watching cartoons on that nice warm floor.

[@plumbbuildrenovate]

ughhh... I love radiant. Your system was badly designed and installed. Each area should be separately zoned.

[@guygadbois1068]

You lose the thermal mass of a massive slab with an in-screed system though!

[@destro513]

Only adds 130k to the price of your house

[@BittyVids]

You’re way too hard on yourself man. Not cringe at all.

[@pacificconstructionradiant168]

improper install

[@capitol699]

What do you take issue with?

[@pacificconstructionradiant168]

@@capitol699 No Thermal Break

[@SScogin]

Doesn't look like the slab is at all insulated (if that picture in the beginning was of his build).

[@ColinBollinger]

your system was poorly designed and installed. but thanks for doing this video as it is awesome your giving feedback about it. should have had more pipe in the bathrooms and where the concrete was more mass.

[@ColinBollinger]

crazy how structural strong your floor is. we would never need that much concrete in Canada and we have strict codes. It must have been expensive as you probably use about 4 times more concrete then we do. surprised that you don't put any structural steel reinforcement bar in it only the mesh grid. great video thanks

[@ColinBollinger]

we put insulation foam under slab or under the pipes. your system should have had a dense foam break about 6 inches down.

[@ColinBollinger]

ya you should have gone with the in screed. more expensive thought

[@ColinBollinger]

wall hung cabinets in the bathroom with keep you toes very warm cause you could put pipes right under your toes.

[@ColinBollinger]

no decorative concrete would not mix with the other concrete as you would pour it later after the first layer is dry

[@mujkocka]

Gas... not green

[@drillbabydrill123]

so

[@LincolnLog]

Gas is a natural product.

[@TheRealMonnie]

Greener than using forced air heating.