BlankI've read his columns for a couple years.  Wonder if anybody has worked 
him; he lives in the New Hampshire area, I think.
Steve, K8SP


DEAR DONNA: Let's cut to the chase. Do you like to eat toast? Have you ever 
burned a piece of bread in a toaster? That's the proof you need to know that
electric heating works and can work quite well. But realize that electric 
heating systems made to be in a ceiling or a floor do not glow red or orange
and cause things to catch on fire. The coils in these systems produce a heat 
that's more like a warm moist towel a flight attendant gives you just before
landing when you sit up near the front of the plane. The most likely reason your 
childhood home was uncomfortable was that not enough heating coil was
put into the house. So there wasn't enough heat generated to offset the heat 
loss that was happening in cold weather. To give you an extreme metaphor,
think about how futile it would be to heat a large warehouse with a tiny 
campfire. Here's what you need to know about electric floor heating. I'm writing
this column right now in my cozy, warm ham radio shack. It's a comfortable 72 F 
inside the room while frost is coating everything outdoors as I look through
my large picture window. There's a wonderful electric coil floor mat under my 
handsome rough oak laminate floor. This heating system keeps my room warm
even if the temperature outdoors drops below zero. It works in my situation 
because the floor heating mat was designed for my heat loss. It can easily
produce more heat than is lost through the walls, floor, ceiling and window. The 
same would be true for your home or any room where you install this device.
My radiant floor electric mat came with a dandy wall thermostat that contains a 
tiny computer. You can program the thermostat to turn on and off depending
on your schedule. You can override the computer and just set the temperature to 
be constant if you desire. The cost to heat with electricity varies depending
on where you live. The key to keeping your costs low is to invest heavily in 
insulation so the heat you create with the electricity seeps outdoors only
slowly. That's what I did in my shack. There's lots and lots of insulation. Be 
sure any windows and other openings are sealed well against air infiltration.
Air leakage is one of the biggest enemies of any heating system. Tiny vampire 
air leaks that may seem innocent add up and rob you of both comfort and money.
The various electric floor heating systems work in the same way, but the 
installation may be different. You need to research exactly what's required 
before
you start. In my situation, the manufacturer of the fiberglass mat that 
contained my heat coils required that the mat be set in wet thinset that's used
to install ceramic tile. This was easy to do. After that step I had to cover my 
mat with an additional quarter-inch of thinset. My floor looked like a
cement slab after I was done. This thinset protects the coils from damage caused 
by the finished flooring that lays on top of them, but it also spreads
out the heat under the entire floor because the mortar conducts the heat. There 
are no hot or cold spots in the floor if you lie on it. It's luxurious
heat, to say the least. The most critical thing to consider when installing 
electric radiant floor heating mats, in my opinion, is the soundness of the
sub-flooring. You don't want the floor to flex or bend as over time, as this 
could cause the electric coils to break. If you have any doubt about this,
have a conversation with the manufacturer of the electric floor mat you decide 
to install. Read all the instructions that come with the product and do
not deviate from them. Don't assume that you know better and that what's 
recommended is overkill. Realize that once this mat is installed, it's virtually
impossible to replace it without great effort and expense. It's very wise to 
read all the instructions even if you intend to have another person install
the mat. If you do this, you'll be able to make sure everything is fine and that 
you'll not have issues down the road. The other benefit of doing this
is that you can ask pointed questions of the contractors who are bidding your 
job. Don't assume for a moment that the contractor, or sub-contractor, will
know exactly how to install the electric heating mat!

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