Electric hydronic radiant heat
I’m designing a cottage for my mother, to be built in central Vermont next summer. It’s 20′ x 34′ single story, probably shed roof (16′ high on south exposure, 12′ on north exposure). Wall assembly isn’t totally hammered down yet, but likely 2×6 walls with cellulose in cavity and rigid foam on exterior, lots of cellulose in the roof, and careful air sealing throughout (the envelope is very simple in order to make air sealing easier). Goal for R values will be 30-40 in walls and 60 in roof.
My question is about heating the building. I installed radiant floors with a gas tankless heater in my own house, and I really love it, and would like to do the same for her. But I’m also interested in keeping all the utilities electric, so that we can reach net zero by adding a small PV array. I know I could just go with a heat pump, but I really don’t like them, for several reasons – I don’t like blown air, and I don’t like having an ugly compressor outside the house. So, my question is: is it crazy to use an electric hot water heater to heat hydronic floors? My sense is that in a building this small, built to fairly high performance standards, it would probably work out ok.
Please note this question is about using an electric water heater for radiant, not so much about the pros and cons of radiant heat. I know it’s not for everyone, slow to respond, etc., but I really like it.
Thanks very much,
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