Is Radiant Right for You?

Answers to often asked questions will help you determine if radiant heating is right for you:

Is radiant expensive to operate? In almost all circumstances radiant heating will be less expensive to operate than conventional heating systems such as central forced air. Ducted systems have higher transmission losses than water flowing through pipes and with a radiant system's ability to be zoned, areas not being used can easily be turned down or off to conserve energy.

Can radiant be installed in my existing house?  With all the radiant products available, there is certain to be an application to deliver radiant heating to your project.  Depending on construction type, retrofit applications can go beneath your floor (Staple-Up), or over your exiting floor (Warmboard, Thermalboard, electric mats, etc.) if you are installing new floor coverings.  Radiators are also a good retrofit application.

How much does it cost?  In most cases, radiant heating will cost more to install than traditional heating systems.  There are many factors that will determine the cost of a radiant system.  These factors must be evaluated on a case-by-case basis.  It is NRDC’s experience over thousands of jobs that systems can be installed for as low as $5/sq. ft. of conditioned space up to $12/sq. ft.  In special circumstances with special needs, installation may cost more.  Depending on your resources and abilities they may also be installed for less.  Estimates reflect complete installed systems inclusive of all materials including heat source and labor.

How long will it last?  The radiant delivery system (tubing, manifolds, etc.) will typically last the life of the home.  Most manufacturers warranty their pipe for 25 years.  Heat sources (water heaters, boilers, etc.) can last anywhere from 8-30 years depending on equipment selected and if regularly maintained.

What happens if a pipe breaks in my floor? The piping used in floor heating systems is cross linked polyethelene (PEX) pipe which is very tough yet flexible and has shape retaining “memory” which makes for a product that should last the life of the home.  The system is run at low pressures (10-20 psi) so very little stress is put on the components and tubing.  A leak would be the result of a catastrophic event (All of NRDC’s designs survived the 1989 7.9 Loma Prieta Earthquake) or damage during installation.  If such an extreme event occurs, the leak must be accessed and a coupling is put in place.

Will radiant heat my entire house? Depending on the type of system installed, floor coverings used, and region installed, radiant floor heating will typically provide for 100% of the heating need.  In rooms of high heat loss (poor or high amounts of glass in cold climates) that require a heat output that is unattainable by the floor, supplemental heat may be required.  This can be provided by radiators, a fireplace or other secondary heating source.

Will I need a boiler to run my system?  As is a feature of many hydronic radiant floor heating systems, the water temperatures required are low (90-140F).  Water heaters can often be used and are a very economical heat source.  High efficiency modulating boilers are a good choice for larger homes and can be used to provide radiant floor heating and domestic water generation as well. 

Can I install any floor covering over radiant floor heating?  There are many types of floor heating systems available today.  Most radiant manufacturers will have specific guidelines for installation of floor coverings over radiant heating.  As part of the design aspect, the floor coverings must be considered when determining the type of system to be used.  In most cases at least one type of floor heating system will be able to be used with any floor covering.  Always consult with the flooring manufacturer regarding the installation of their product over radiant heating.