What is the best heating system for new home build?
Hi Folks, I’m hoping someone will be able to provide some advice on a choice of heating system for my new build. It will be a 1200sq ft IFC bungalow with a 4’frost-wall slab. It will be located in Cape Breton, Nova Scotia.
I am leaning towards radiant in-floor heat (hot water) with a propane boiler, but I’m starting to 2nd guess if that is the right decision. I had an energy assessment done based off my home plan and 12,000 Btu/h Minisplit, HSPF 12 was recommended with a Hybrid Heat Pump water heater based on Region 5.
My concern with the heat pump is I want a heating system that offers even heat distribution, and I especially don’t want cold floors, hence why I’m leaning towards in-floor heating.
Does anyone have advice if my choice of in-floor heating is a good choice? And if so, is a propane boiler a better option over an electric water heater? Or should I go with the heat pump?
Thank you for any advice.
What you are suggesting is exactly the way we do it – start a home on a slab on grade with in-floor radiant heat. I’m going to pitch you a list of articles to read that cover most of what you are asking and we can take it from there.
First, we would only ever choose electric heat, fossil fuel heating is on its way out. read more here – Why Electric Heating Systems are Best for Zero Energy Homes
As for the slab on grade with frost wall – an alternative to explore is a raft slab frost protected shallow foundation with air heated radiant floors, that is what we built in our recent LEED Platinum demonstration home. They can be heated with gas or electricity; we of course chose electricity. An option with that could be to use an air-to-water heat pump for preheating water before it goes to a boiler.
As for the concept of heating with electricity - Cape Breton seems to have variable power rates, and the raft slab mentioned above provides so much thermal mass that with an energy efficient home you would easily be able to set a timer so it only heats during off peak hours, which can make it quite affordable.
As for not having cold feet, good call. Cold feet leads to people jacking up the thermostat to compensate, whereas if you had warm feet you can keep the air temperature in your home a bit cooler because the surfaces you are in contact with give heat to your body rather than steal it. Read more about that here, in our page about how to design a home for thermal comfort. When you heat a floor you will obviously have happy feet, but you increase the differential in temperature between your concrete floor and the ground below, so don’t skimp on insulation!
For a climate like Cape Breton, you would be wise to have 6 to 8 inches of insulation below your slab. Not much more, but not much less either for comfort and cost efficiency. Read more here about how much insulation does a basement need? Look those pages over and get back to us if you have follow up questions, we’re always happy to help.
Emmanuel, thank you so much for the detailed reply. You helped me make one decision already. It's going to be electric heat. Sounds like the key will be to ensure I have a solid building envelope with no thermal gaps. The Legalett system I brought to my contractor last spring but he wasn't familar with it and I wasn't confident enough of my own knowledge of it so I put it on the backburner. But, I'll read through the articles you suggested and chat with my contractor about it all again. I need to make sure I'm building for the times. Thanks again for your help!
Glad to hear it, electric is the way to go. The Legalett slab on grade form kit is not at all complicated, it comes with custom step-by-step plans as well as online training for installers, so any builder who has a sense of how to follow plans can pull it off no problem, but builders are always reluctant to try stuff they don't know. We can't speak to how it compares with other systems price-wise, but these slabs are very well-designed and insulated, so you won't find higher quality at least.
Mike, thanks for your input. I am going back to my contractor about it. Sticking to my guns:)
Hi Maureen .Just read this blog, and wondered how you got on, and if you used the legalett system..