Electric Floor Heating System
Tips
For Choosing And Installing An Electric Floor Heating System
by Georges
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 longtime. The Roman Empire was
known for its luxurious public 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 bath floors.
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. Products sold by WarmlyYours.com
Inc. (www.WarmlyYours.com ), DK Heating Systems (www.dkheating.com
), and NuHeat (www.nuheat.com) have been installed for approximately
10 years in Europe and in north America. In the last two years
Heatway Inc (www.heatway.com) and Flextherm Inc. (www.flextherm.com)
have introduced new products in the US market.
All these
products are 1/8" thick and they 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-&-turns to fit the custom shape of each room. NuHeat
offers standard size rectangles and special orders made-to-size
mats. WarmlyYours.com offers both rectangular mats and rolls.
These rolls or mats always have to be used entirely and the
cuts-&-turns only allow you to cut the supporting material
to facilitate the turns (see illustration). You never cut
the heat resistance wire!
With so much choice in the
market, the DIY consumer is having a harder time to choose.
Once installed the product is hidden under the floor. Even
the thermostat can be hidden in a closet since it functions
with a sensor in the floor and it does not measure the air
temperature.
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-&-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 installation.
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.
