Best Flooring Options for Radiant Heating
Radiant floor heating is a luxurious home feature and a popular trend — in new housing and home renovations — that focuses on clean, comfortable living.
There are two types of radiant floor heating, electric and water-based systems. Both provide heating in a room from the floor up for consistent, efficient warmth. Warm water systems run hot water through pipes to create heat, whereas electric underfloor systems heat wiring beneath the floor to generate warmth.
Traditional radiators need to be heated to a high temperature (between 149-167°F) in order to heat up a room effectively. Whereas floor heating only needs to run at a temperature of 84°F or less, depending on the floor finish, in order to warm a room – thereby consuming less energy. Radiant heat provides an average saving of 15% on heating bills thanks to the efficient way it warms a home.
In addition, radiators heat the air nearest them first, causing rooms to be prone to “cold spots” where the air feels cold in the middle of the room and very hot next to the radiators. Radiant heat provides warmth from the floor up throughout the room without any cold spots or stuffiness in the area being heated.
Best flooring materials for radiant heat
Properties that make a floor covering good or bad for radiant heating systems tend to center around the thickness of the flooring, the flooring's thermal conductive nature, its tendency to expand and contract, and whether it is prone to water and heat damage.
Thicker floor coverings like solid hardwood and engineered wood are poor thermal bridges. Mineral-based floor coverings, like tile and stone, are excellent thermal conductors. Tile and stone do not expand or contract. Solid hardwood can easily be damaged by heat and moisture.
Porcelain, ceramic, and natural stone are the best flooring materials for radiant heating as they encompass all four factors. On top of it, tile tends to feel colder than other types of flooring, so the need for radiant heating underneath it is greatest.
The worst flooring — carpeting — fails on almost all of the points.
Porcelain and ceramic tile are ideal for use with radiant floor heating systems. Not only is tile thin but its mineral-based nature means that it conducts heat well. Additionally, since tile contains no organic products, it will not rot or degrade if a hydronic system leaks water. Tile heats up rapidly as soon as the system turns on. Tile, too, retains heat for a short while after the system shuts off.
Natural stone flooring or aggregate stone is a natural fit for radiant heating systems. Not only is stone safe to use over radiant heating, but it also retains heat for a longer period than tile after a system shut-off. Natural stone flooring is slightly thicker than ceramic and porcelain tile, so it heats up a bit slower than tile. But it does retain heat for a long time, it never expands or contracts, and it cannot degrade.
Laminate flooring is thin and allows the heat to penetrate and dissipate. Precautions must be taken to protect the flooring, though. In hydronic systems, should moisture escape, the laminate would be permanently damaged. The temperature of the system must be kept below the maximum point that is recommended by the laminate flooring manufacturer (approximately not over 85°F). One benefit of laminate flooring on its own is that it feels warm underfoot. The wood content in the laminate base, combined with the foam underlayment, makes for a generally comfortable feeling. So, you may want to use radiant heating under laminate flooring only in very cold rooms.
Sheet or tile vinyl flooring can have radiant heat systems installed under them. Check the manufacturer's installation instructions for maximum temperatures. Generally, begin with 70°F during the first 24 hours of use, increasing to no more than 85°F.
Engineered wood flooring is recommended as a better candidate for radiant heating systems. It employs high-quality plywood as a base for its top layer of hardwood veneer. This type of plywood is dimensionally stable and does not quickly respond to temperature spikes or drops. However, wood is a poor thermal conductor. This means that heat from the system will not transmit as quickly or as thoroughly as with thinner floors that are more thermally conductive.
Solid hardwood flooring works better with radiant heat if it is quarter-sawn instead of plain-sawn. The heating element should be embedded within a sleeper system subfloor, under a traditional subfloor, or embedded within concrete. Narrower floorboards tend to work better than wide plank because the multiplicity of seams allows for more flexibility if the floor should expand and contract.
Floors that should not Have radiant heat flooring
Rubber flooring does not react well to high heat and may give off unpleasant odors.
Radiant heating can dry and loosen the adhesive on glued-down carpeting. In fact, any type of flooring that employs adhesive as its joining system is a poorer choice for radiant heating systems than flooring that uses tongue-and-groove or fold-and-lock seaming.
Concrete is a poor choice for radiant heating. Radiant systems require layered flooring so that the tubing can be hidden under the top layer. However, radiant heat systems can be embedded in concrete floor slabs, as long as a subsequent top floor covering such as tile is added.