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Tips For Choosing And Installing
An Electric Floor Heating System
by George Selvais
No one takes a cold shower in the morning, and everyone prefers to step
on a warm floor. Warm floors have been around for a very long time. The Roman Empire was known
for its luxurious baths with hot water springs that circulated warm water under the marble floors.
Nowadays, you don't need a hot water spring in your backyard to enjoy the comfort of Roman
A thin electric mat installed in thinset cement or self-leveling cement, controlled by a timer-thermostat with an in-floor
sensor will cost $500-to-$600 for an average size bathroom and it will operate
on less than 10 cents a day of electricity.
Conceptually, these products are very similar to electric blankets. They are
made of a heat resistance wire that serpentines over a supporting material. They
are safe, relatively easy to install, and extremely energy efficient with a
track record of over 20 years of successful installations!
The electric mats are about 1/8" thick and can easily be embedded
in thinset cement without elevating the floor more than 1/8".They will all
draw 8-to-15 watt/ sq. ft. and each of these manufacturers offer rolls of
different sizes so that the installer can make cuts and turns to fit the custom
shape of each room. NuHeat offers standard size rectangles and special orders
made-to-size mats. They are available in both rectangular mats and rolls.
These rolls or mats always have to be used entirely and the cuts and turns only
allow you to cut the supporting material to facilitate the turns (see illustration).
You never cut the heat resistance wire! Products of equal watt/ sq. ft. will warm the floor to the same
temperature and at the same speed.
Finally, many timers and thermostats offer comparable functions,
so the real difference is the ease of installation and the level
of technical support offered by the manufacturer.
What makes the installation easy?
The mat or roll construction: You want to look for
a product that can be installed in a single layer of thinset cement rather
than two layers. This is faster and easier. You also want to find a product
where the fiberglass (or other supporting material) forms an umbrella protection
over the resistance wire so that your trowel can glide over the fiberglass
net without risk of nicking the wire. Some products weave their wire over-and-under
a fiberglass net. In that case the resistance wire will always appear on the
surface and you face a greater risk of nicking the cable with your trowel
Thickness of the cold-lead wires that connect the heating rolls to
the thermostat: You want the thinnest cold-lead wires available (1/8" thick),
so you can easily cover them with thinset cement like the heat resistance
wire. If the cold-lead wires are thicker you will need to chisel a grove in
the cement slab, or use a circular saw to cut a groove in the plywood sub-floor
or backer board to maintain the floor level flat.
Length of the cold-lead wires: You want cold lead wires that are
long enough to connect to the thermostat without additional cut or turns of
the roll to bring the roll closer to the thermostat.
Vendor Technical Support: Look for a vendor who will design an installation layout
customized to your own floor plan. Understand that the heat will not extend
very much laterally through conduction. In most cases the heat will extend
1.5" away from the wires but not more.
Therefore it is important to lay the heating mat 1" or 2"
under the toe-kick space to make sure you don't end-up standing with hot heels
and cold toes in front of your vanity. Attention to details and precision
in your customized design layout will save you time and cost during the
How to make a successful electric installation ?
Make sure you have a good ohm meter and continuity checker.
Check the ohm resistance at least three times: before you start, after you
laid the heating element in thinset cement, and after you installed the tile
or stone over the heating elements. There is no need to fire-up the system
with 110 volts to make sure you have a working installation.
A proper ohm reading will confirm that you have no break
in the cable, and the continuity check will assure you that there is no short
passing through the insulation that separates the core wire and the ground
shield. Any DIY who can install ceramic tile can install
a floor heating system and bring the cold lead wires behind the thermostat.
However to install a timer and thermostat and connect them to the floor heating
you need to hire an experienced electrician.
Once properly installed these floor heating systems are a
marvelous part of our daily comfort. They are totally silent. They do not
circulate hot air that carries bacteria and toxins. They have no moving parts
and require no maintenance. Whether you plan a new bathroom,
a kitchen, a sunroom addition or a basement conversion, floor heating is the
sensible solution for comfort and energy savings. They can be installed under
tile, stone, vinyl, carpet, hardwood and laminate floors.
About the author: George Selvais, is
the general manager of WarmlyYours.com,
and online source for top quality radiant heating systems. He was educated at Harvard
and traveled extensively in Europe where he has investigated the floor warming
industry extensively before starting his very successful online business.
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