Warming, granite counters, pedestal sinks, toilets and bathtubs
I saw that in the FHB article by Tom Meehan, that you are not supposed to use electric radient floor heaters under the above items. How does one warm these cool to the touch items if such luxury is in the budget and planning? Also, Why cannot electric radiant heat be used as a primary heat source?
Thanks for your wisdom.
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Replies
Hal,
Are you referring to Tom Meehan's article in Fine Homebulding #159, from November 2003?
You don't want to install radiant heat under a granite countertop because countertops are sometimes used as places to put an ice cube tray, a stick of butter, a box of chocolates, a tub of Nivea cream, or a tube of cocoa butter. These are items that you don't want to melt.
You don't want to install radiant heat under a toilet because the heat can melt the wax seal, leading to sewer gas leaks.
You don't want to install radiant heat (especially electric radiant heat) under a cabinet or bathtub, because the wires can overheat, leading to a possible fire hazard.
If you really want to, you can use electric radiant heat as a primary heat source for your whole house. In most homes, this type of heating system would require special high-amp electrical service (usually a 200-amp panel). If your house has a 100-amp panel, upgrading to 200-amp service is expensive.
Remember, electric resistance heat is one of the most expensive ways to heat a home. If you go this route, you need an excellent thermal envelope (thick insulation, low rates of air leakage, and above-code windows). You may still end up with high energy bills.
Remember, too, that electric resistance floor mats have an uneven record for reliability. Sometimes these mats fail.