Installing a Radiant Heat System
By Rob Robillard
Consistent performance, easy installation and simple climate control—Electric radiant heat warms the home from the floor up.
New England mornings can tempt some of the toughest to roll over, turn off the alarm clock and go back to sleep. Getting out of bed and stepping onto a cold wood or tile floor can send chills up your spine and set the mood for the day.
Research is showing that more and more people are remodeling their homes instead of moving or building new. In addition, 60 percent of homeowners 50 years and older intend to stay in their homes through retirement, which also means aging-in-place remodeling.
Using electric radiant heat as a remodeling solution occurred to me several months ago while working on a bathroom that was located above my client’s garage. It was February and the floor of the tile bathroom was frigid.
In these situations using electric radiant heat to supplement the existing heating system is a no-brainer and can instantly create a warm, toasty, supplemental heat source in any room—especially in bathrooms.
Why Radiant Heat?
As technology continues to advance, so has the concept of floor heating. Although floor-heating dates back to ancient Roman bathhouses where slaves tended fires sending hot air through channels under elevated floors, it has not until recently become popular within households.
Many people are familiar with hydraulic under-floor heating systems that require tubing to run a hot liquid beneath the floor, along baseboard heaters or through radiators to heat your home. Yet an alternative to hydraulic heating that is easier and more cost-effective to install is electric under-floor heating.
The science behind electric radiant floor heating is quite simple: The entire floor surface effectively becomes a low-temperature radiator.
These electric systems transfer the heat directly to the floor surface via infrared radiation. The floor in turn warms the people and other objects in the room.
Floor heat is much more efficient and comfortable than heating the air, which does not retain that heat for very long. Unlike forced-air heating systems, under-floor heating warms your body and the objects surrounding you rather than heating the air, ultimately eliminating inconsistent room temperatures and reducing the percentage of dust mites.
When you’re purchasing electric floor heating, you want to make sure that it’s as “hot” as possible—for this, pay close attention to the watts-per-square-foot ratio.
The optimal wattage is 15 watts per square foot. The bottom line is: The hotter, the better! With 15 watts per square foot, you will be able to utilize full heating technology for a faster heat-up and a warmer floor, especially valuable in a bathroom installation where time is spent morning and night for our daily routines.
Where can Electric Radiant Heat Be Used?
Electric floor heating can be used indoors or outdoors. It can be installed under many types of flooring, including laminates, hardwood and tile. The system consists of electric cables built into the floor, or it features mats of electrically conductive plastic that are mounted on the subfloor.
The system can be installed on a mortar bed or gypsum board with only a thin layer of thin-set cement between it and the floor tile.
Retrofitting during a remodel is easy and usually does not significantly raise the floor height.
Electric floor heating systems come in several different forms, such as a mat or cable to accommodate the various size and shape of the area. For complicated areas, a single heating cable can be used under the floor. Heating mats are more likely to be installed in simple areas with more square footage. Using the mats allows retrofitting over existing slabs without significantly raising the floor height.