What is radiant heat?

Like the sun, radiant heat warms objects directly with longwave electromagnetic energy. It warms a room sooner and at lower temperature settings than other kinds of heat making it more efficient.

Radiant heating uses a warm surface to transfer heat to individuals and into a space rather than moving heated air.

What are the different types of radiant heat?

There are many types of heat that are considered “radiant” some of which are detailed below, some others include, fireplaces, wood burning stoves and snow melt systems.

Natural Gas unit heaters, or space heaters, can be installed in almost any area of your home and individual temperature controls mean heat is only produced where you need it. These come in portable units as well as baseboard and wall units. A radiant room heater has a burner below a set of elements called radiants.  Radiants for unvented heaters are made of ceramic and glow red-hot, which radiates into the room. Ensure that unvented heaters are burning correctly, or they can release dangerous carbon monoxide into the room. Vented room heaters often have circulating blowers in addition to radiants. Unvented heaters release the by-products of combustion into the heated spaces and are 100% efficient, where vented units are 80% efficient because the remaining heat rises up the flue. You can purchase these units through your local gas company. Gas-fired radiant tube heaters are suitable for heating larger open areas such as garages, arenas, commercial buildings, etc. These “luminous” type units are most commonly suspended from the ceiling and feature external combustion on a surface brought to temperatures between 750 and 900 degrees Celsius.  In these heaters, an air gas mixture is injected through ceramic plates. The air used in combustion is from inside the building. These infrared lamps evacuate the gas burned into the area to be heated, presenting no danger to hygiene or health.

Hydronic heating is gaining in popularity for its comfort and efficiency. Widely used in Europe, this quiet system uses a compact boiler or water heater to heat water and distribute it through piping a little bigger than the diameter of a finger. The heated water runs through these pipes to baseboard heaters, behind walls, ceilings or alternately, to plastic tubing installed in floors providing gentle radiated warmth. These floors can be concrete or any type of solid or suspended floor. Since most homes have different floor coverings that can restrict the heat flow through the floor, the hydronic underfloor system includes small electrical (24 volt) valve heads that automatically shut off water flow at different intervals. They are controlled by room thermostats . Choice of fuel, whether it is gas, oil, propane or you choose electricity,  is a personal preference or one of economics.

Electric radiant heating systems are easy to install, requiring no ducts, pipes, furnaces, or chimneys, and the installation costs less than that of nearly all other systems. In addition to baseboard, wall mounted and ceiling panels, there is also electric in floor heating.  Although not yet a common radiant heating system, there is a gypsum board electric radiant coiling heating system available. It installs like gypsum board and is equipped with factory-embedded heating cables.

Are Radiant Heating Systems more economical?

The combustion efficiency of natural gas units stands around 80%. Gas radiant heaters are said to save between $228.00 and $522.00 per year (depending on BTU) as compared to electric and propane heat.

Hydronic floor systems, although costly to install, cost up to 40% less to operate than traditional methods. When remodeling and installing an electric heating system in a small addition, you can expect to spend approximately $500 to $750 whereas an equivalent hydronic system would run $4,000 to $5,000. Hydronic systems have high start-up costs because you have to buy a boiler.

For maximum cost savings, radiant electric heat panels can be zoned for individual rooms or wired to motion detectors so that rooms are heated only when they are occupied. A study comparing radiant heat panels with conventional convection heating systems and electric baseboard systems showed that during a typical year of heating, radiant heat panels energy consumption was 7,229 kwh, whereas heat pumps consumed 10,764 kwh and electric baseboard systems consumed 15,107 kwh.

Problems with radiant heating systems

Ontario Hydro has warned homeowners that Flex-Heat electric radiant ceiling heating, installed in the late 1970’s, is dangerous and that the system can fail without warning and may become a fire hazard. This system must be disconnected immediately if it hasn’t already. Most houses with Flex-Heat have a label on the electrical panel box or a label on the thermostat indicating that it is a Flex-Heat system.

Radiant hydronic floors installed in the 50’s used steel and copper pipes buried in the slab. Lifespan for these pipes proved fairly short and many systems had to be abandoned after only 15 – 20 years. The problems were mainly caused by thermal expansion and contraction of the pipes, which were held by concrete, causing stress and fatigue system failure which included shifting and corrosion of the slab. Special high grade plastic tubing, especially developed for under floor heating has since taken the place of copper and steel. Since hydronic systems have water continuously circulating, they use valves and manifolds, which are prone to sedimentation, mechanical problems and maintenance issues.

Who installs radiant heat systems?

Installation is usually done by an electrician or qualified heating contractor with a gas fitters license. While a building contractor or home owner can often set the heating elements or panels in place, a qualified electrician should do the actual electrical hook up. Electric systems are hardwired into regular house wiring following the manufacturer’s instructions. Radiant hydronic floor heating must be installed by certified technicians or heating contractors. Hydronic systems are quite costly to install because they require tubing to transport liquid, a heat generator (water heater or boiler), possibly transfer plates and considerable engineering. Pricing is based on several variables like if the construction is new or old, if the construction is loose or tight with little insulation or a lot and if it’s slab on grade or if the tubing is stapled directly to the sub floor with heat transfer plates in between. Heat transfer plates are designed to heat the floor structure by conductive heating.

What are the advantages of radiant heat?

No heat is as healthful and safe as radiant heat, which produces no chemicals, dust particles, odors, or fumes. A must for asthmatics, arthritis sufferers, persons with allergies or chemical sensitivities.

Correct location of radiant heaters ensures that cold spots are avoided. Radiant heaters minimize roof heat losses by directing heat downwards to the area that requires the heating. With radiant heating systems, you can set your thermostat 6-8 degrees lower than with other heating systems.

Manufacturers of radiant heat systems

Alcatel is one of the worlds largest manufacturers of heating cable and warming mats.

Lennox Industries Inc. headquarterd in Dallas Texas with distributors throughout the United States and Canada not only manufactures gas-fired heating units, but also radiant floor heating products.

Easyheat has manufacturing facilities in the United States and Canada, specializing in complete electrical radiant heat systems, including cables, controls and all materials required to properly install and use these systems.