Radiant Heat 101 – Comfort & Efficiency - AplosGroup

I love my radiant heat. There’s nothing cozier on a chilly winter morning than a toasty warm floor greeting your cold feet.

More and more, clients are asking me about radiant heat for their homes. What used to be thought of as a luxury is going increasingly mainstream, thanks to the comfort and energy efficiency of modern heating systems.

What is Radiant Heat?

There are two main types of radiant heating systems used in residential buildings: electric and hydronic.

Electric systems use an electric cable mesh in the subfloor in mats to deliver heat to a room.

Hydronic systems use heated water pumped through under-floor tubing to heat a home.

Both types of radiant heat can be installed on top of a home’s subfloor using panels or grids embedded in a layer of concrete. The system is controlled via the home’s thermostat.

Many mid-century modern homes (such as Eichlers or Alliances) have existing hydronic radiant heat systems in which the tubing is embedded in the concrete slab. Because these systems used copper or stainless-steel piping (rather than the durable polyurethane of today’s radiant heat systems), they may break down and leak. In this case, the old system can be shut off and a new, modern system laid on top of the subfloor.

Benefits of Radiant Heat

Radiant heat is generally more energy-efficient than forced-air or baseboard heating because:

It is a “smart” solution to heat a solid object that will hold heat and “radiate” it out for a period of time instead of heating the air
There is no heat loss through ducts
Heat is distributed uniformly from the floor upwards – no cold spots
It warms entire room from floor up
It provides flexibility because it can be connected to a wide variety of hot water sources – you can select based on what is the most cost-effective in your area

Bonus – Radiant heating is especially good for those who suffer from allergies, as there’s no air blowing allergens around the home.

Caveats

I recommend radiant heating to many clients because of its superior comfort and energy-efficiency, but it isn’t right for everyone. Here are a few caveats:

The initial installation cost may be higher than for forced-air systems where the ducts are already in place (this may be offset by energy savings over the life of the system)
You have to choose your floor coverings carefully – anything that insulates the floor (such as thick carpeting) can reduce the system’s efficiency (ceramic tile is ideal)

Installing Radiant Heat

Because installation requires access to the subfloor, the best time to install a radiant heat system is when you are redoing your home’s flooring.

It’s important to use a contractor with expertise in radiant heat. Fortunately, there are several specialists in the Bay Area – your architect or general contractor can recommend a reputable radiant heat specialist in your area.

Maintaining a Radiant Heat System

If your home has an older copper or stainless radiant heat system and notice a loss of efficiency, you may have a leak. Radiant heat specialists can provide leak-detection services and, sometimes, repairs.

Modern systems are far less prone to leaking and, with no ducts or filters to get gummed up, are largely low-maintenance. Nevertheless, there are a few things to do to keep your system humming along perfectly:

Have the system pressure checked yearly,
If you notice any unusual noise, have the pump and valves inspected (the life-span of the pump is around 10 years)
Follow manufacturer’s maintenance recommendations for the boiler or water heater
If your system uses glycol to prevent freezing (more common in areas that experience cold winters) have the pH levels checked yearly (it may need flushing and refilling every 5 to 7 years)