Since the electric cables will probably be in contact with the slab, and since the slab is probably thermal-bridged to the outdoors or to mother earth, I'll agree that it might not be a suitable solution in this case. In this case, consider putting cables under a 2cm quartz countertop and the 2cm quartz side panel at the end of the countertop run. The goal here is to keep it warm, generating constant heat, radiating constantly. Not so hot that it would melt butter. But, there is still a lot of information unknown, unwritten, unexpressed so far. It may be possible to heat a thin ceramic tile (e.g. Kerlite) and to install a thin membrane between the slab and the heating cables. Post again. It IS possible to get sufficient heat from electric cables to heat the kitchen entirely. There are many reasons for this. It is a lot of work to write it all out, and later to refute the naysayers who find it hard to believe, so I will abstain from this work at this time.

Hi Alphamale I went with the Navien NCB 240 which was installed at the end of last July. As it turns out it looks like this boiler is insufficient for my needs probably because of the heat demand required for an indoor pool. I'm still not convinced that even without the pool it may still be insufficient in that I run the heat to the pool for only 12 hours per day and when the only heat demand is for the 1,400 sq. feet of house and domestic hot water for 2 people it still has to work hard to get the heat past 70F. Between 7 PM and 7 AM and when it's cold when the pool and house are calling for heat in the morning the house has gone down to 66 F. This is weird because a contractor told me he installed two of the NCB 240s to heat three floors of 10,000 sq. feet each. I spoke to another highly recommended contractor who did an analysis and concluded that the NCB is in sufficient. I have calls into the local Viessmann distributor and another highly recommended contractor for input and recommendations. I am considering using a separate pool heater but it turns out the only one I can install indoors costs $8,000 plus 13% HST plus installation so that could turn into another 10 grand. I can get an outdoor pool heater but I suspect it would cost 5 grand for the heater plus a custom built shelter for it. Another possibility is to get a propane heater insert for the fireplace which would allow more boiler BTUs for the pool. At any rate Dan, depending on your requirements I would recommend converting to propane if only because that's the direction things are going. OIl for heating is quickly going the way of the dinosaur not to mention a big savings in fuel. From my own research if I had it to do over again I would take a close look at the Veissmann and Trinity boilers and there may be others. So far my experience is turning out to be a horror show so be careful.

I am curious as to why you say an air sourced heat pump is not a good choice for your climate. If you will have net metering then are you able to sell any unused electricity back to the utility company? If you can then powering you electric boiler is not free. It is hard to estimate, but 5 - 6 kW of solar panels is about what you will need to power the house without the electric boiler. If you post your propane and electric rate a calculation can be done to determine which will be more cost effective. If propane is cheaper, than you could also use it for cooking, drying clothes, and domestic hot water.

I am in St. Louis, with four true seasons. I currently own a mid century modern home with only a slab and radiant heat. So we have a boiler for our radiant heat and central air. I love our home, but we usually have to go to my in-laws when there are tornado warnings and shelter in their basement. I looking for the best of both worlds with a slab and partial basement, but it may come with a hefty price tag. I just can't tolerate forced heat...it's just so smothering for lack of better words.