Primary HVAC systems can’t provide the exact room temperature every building occupant wants. People differ in metabolic rate, their style of dress and their preferences for how warm they want to be. 

The challenge is to offer supplemental heating that can be activated in individual offices and workspaces by occupants who are too cold even when the heat is on in the winter, or who find the air conditioning too effective in the summer. 

The solution is the installation of in-floor electric radiant heat, operable at the local level, which allows occupants to achieve a level of personal comfort in each office or room.

A recent paper published in the journal Nature Climate Change by Boris Kingma and Wouter van Marken Lictenbelt, researchers with the Maastricht University Medical Center in the Netherlands, notes that most office buildings set temperatures based on a formula from the 1960s. The formula primarily used middle-aged men as test subjects and does not address the comfort level for women, who usually have slower metabolic rates and feel cooler in the same heated or air-conditioned space as men. And men typically wear heavier clothing in the office year round, adding to their warmth.

An article published about the paper in The New York Times elicited comments from hundreds of women about how
they had to cover up in heavy sweaters, sweatshirts, leggings, slippers and blankets in order to be comfortable in an air-conditioned office. Today, when about half the workforce is composed of women, the old formula may not be the best choice for all.
In-floor electric radiant heat installed under new floors is a way to offer optional supplemental heating in individual offices and workspaces. The solution can be a very good selling point for renting tenants and a nice perk for owners.

Unlike a forced air system, which moves heated air within a space, radiant heat transfers heat from a warm surface to a cool surface. It is very user friendly. There are no drafts, no moving parts, no ducts to clean and no filters to change, and it does not blow around irritating allergens (a real plus for allergy sufferers). And unlike space heaters, radiant heat doesn’t hum, can’t tip over, and won’t overheat feet or soften vinyl flooring. However, it is important to keep an air gap under any solid bottom furniture (such as filing cabinets and bookcases), fixtures or other items with the use of legs or spacers to avoid excessive heat buildup.  

It is also a good option to supplement primary heating systems in buildings with offices or workspaces that, because of window configuration or orientation with respect to the sun and to prevailing winds, are inherently colder than offices or rooms elsewhere in the facility, as well as an easy way to provide extra warmth in high-ceilinged old factories and lofts converted to offices, as well as mixed-use buildings that include day care and senior care facilities. It also can be installed in reception areas and at cashier stations.

Several manufacturers offer line voltage or low voltage systems designed specifically for floating floors, including engineered
wood, hardwood, laminate, and some floating tile systems, luxury vinyl tile and ceramic tile floors. For tile floors, systems can combine heating elements and a floor underlayment that includes an anti-fracture membrane that isolates cracks in a concrete subfloor from telegraphing through to the tile surface. Some systems are designed for installation under carpet tile.

Most systems come pre-wired. Many can be rolled out directly over a subfloor or over an underlayment and under a finished floor, and just require cutting and fitting into place and connection to the primary power system at a junction box. Other systems require laying out the elements onto a specialized underlayment designed to accept the wiring.

In-floor electric radiant heat systems utilize just a few main components: the heating elements, an in-floor sensor and a GFCI thermostat. The elements can be heating film, heating cables, or heating mats or mesh. The sensor, which is recessed into the floor so it lies flush, monitors the temperature of the floor and generally aims for a setting just a few degrees above room temperature. The thermostat, which is typically wall-mounted, allows occupants of the space to adjust the room temperature. Programmable thermostats enable pre-heating the floor in anticipation of occupancy.

Power consumption is measured by wattage output per square foot. The standard wattage density is 8 watts to 12 watts per square foot, an output that conforms with warranty requirements for most floating floors. It is a good idea to specify and install a system that is tested and UL (Underwriters Laboratories) listed, UL-Canada ETL or CSA (Canadian Standards Association) listed.


Jack Boesch is director of marketing at MP Global Products LLC. For more information, call (888) 379-9695 or visit quietwalk.com.