Once falsely considered too expensive to install, underfloor heating is now making its way into more and more homes. Yet, when making the jump to this heating type, what type of flooring to get is a huge area of concern.
- Most floor options are suited for underfloor heating, which means you have plenty to choose from.
- Underfloor heating is suitable for most types of wood, tile, stone, laminate, vinyl, and carpet.
- Rubber and concrete flooring are the worst options when it comes to underfloor heating.
How to Choose the Best Flooring
Most floor options are suited for underfloor heating (UFH), which means you have plenty to choose from. But what qualities should you consider when it comes to selecting the right flooring for underfloor heating?
Let’s first take a look at how easily heat gets transferred to each type of flooring. Flooring with good conductivity heats up quicker, gives out more heat, and is more efficient to run.
Tile, stone, and rubber floors have very high heat transfer levels while carpet has a medium level. Wood, laminate, and vinyl have high transfer levels, but not as high as tile, stone, or rubber.
(NOTE: Just because carpet flooring doesn’t have high heat transfer levels compared to the others doesn’t mean you can’t have carpet with your UFH. An appropriate UFH system is available for each type of floor!)
Another factor to consider when selecting a floor is the price. Hardwood, natural stone tile, ceramic, and porcelain tiles are pricier, while vinyl and laminates are on the more budget-friendly end of the price spectrum.
Another point to consider is how easy the flooring is to install. Laminate is very easy to install, and vinyl can be a DIY installation. On the other hand, porcelain and ceramic tiles are difficult to install, and you will most likely need to hire a professional to do this.
Best Flooring Options for Underfloor Heating
Let’s dive a little deeper into the various flooring options to give you a more informed decision.
Underfloor heating is suitable for most types of wood flooring. If we compare hardwood vs. engineered wood, engineered wood may not be the best choice since applying too much heat can cause the wood to swell permanently.
Can you still use underfloor heating with engineered wood? Yes, but you have to take extra care and that your floorboards are not over 18 mm thick.
When it comes to hardwood floors, wood with high dimensional stability is better than low dimensional stability. Dimensional stability is measured by the changes in wood’s volume with changes in moisture in its environment.
Some examples of wood considered to have high dimensional stability are black cherry, cypress, Santos mahogany, mesquite, and teak. Wood considered to have low dimensional stability is hickory, beech, white oak, and maple.
When installing your wood floor, the floating installation method is better rather than the traditional installation. Traditional installation involves attaching your new floor to the subfloor using staples, glue, and nails.
In contrast, a floating installation involves interlocking the wood planks, so it doesn’t touch the subfloor. The floating installation is better suited for UFH because it gives the wood room to contract and expand.
Tile floors and UFH are the perfect pairings since tiles are very conductive. Heat transfers quickly to tiles, and they retain it well. You can use either water or electric UFH for tiles.
The tile’s thickness does not affect its heat output but the thicker the tile, the longer it takes to heat up.
Stone and ceramic tiles are the best options because they are the most thermally conductive of all floor types. Their hard surfaces have the least resistance and can transfer heat efficiently.
Porcelain and ceramic tiles are more affordable than natural stone tiles and conduct heat efficiently and effectively as natural stone tiles.
To ensure your tile floor is installed flawlessly, the subfloor must be stable and level. Use a decoupling membrane when installing your tiles to act as a barrier between the tiles and subfloor so that any movement in the subfloor won’t cause your tiles to crack.
Stone floors are also an excellent choice for UFH because of their high heat retention and excellent thermal conductivity. Like tile, the thicker the stone won’t affect the heat output but will take more time to heat up.
Marble is your best bet when it comes to stone flooring because it’s the most thermally conductive compared to other stone types. Other options, which work nearly as well, are limestone and slate
Limestone is durable and is easy to maintain. It also transfers heat quickly.
It is the most affordable natural stone flooring, but you need to take more care while installing it. Limestone also needs to be sealed immediately once installed to prevent any liquid and dirt from entering its pores.
Slate is very heat conductive and is also durable. Slate is resistant to chipping, cracking, breaking, and scratches.
However, it is more expensive, difficult to install, and difficult to repair and replace when needed. Like limestone, you also need to seal slate to prevent any dirt and liquids from penetrating its pores.
When it comes to installing stone floors, we recommend you call a professional to do it to make sure it’s done perfectly, as stone floors are more difficult to lay down.
Laminate flooring is more economical and effortless to maintain than natural wood or stone floors. Most brands are scratch-resistant and water-resistant, making them ideal for people with pets or small children. Laminate is also a lot easier to clean than other floor types.
Laminate flooring is composed of several layers with a core made up of fiberboard, and it is also designed to mimic stone or wood.
One benefit of laminate is that it does not easily change shape or warp with temperature changes. Another edge laminate flooring has over other types is that it interlocks, floating it above the subfloor and leaving a gap between the subfloor and laminate floor.
This gap prevents your laminate floor from buckling when temperatures change, or the area becomes more humid. A 15 mm gap should be sufficient and can be hidden by the skirting board.
It is possible to use laminate flooring for wet and electric UFH systems, but ensure that you only heat your floors to 80°F. Higher than that could damage the flooring. Have a floor temperature sensor so you can easily monitor your floor’s temperature.
Thicker laminate flooring can slow down heat transfer, so make sure your laminate floors are not thicker than 18 mm for efficient heat transfer.
You can also use vinyl flooring with your UFH system. Vinyl is thin, and it can heat up and cool down quickly.
Vinyl flooring, however, is not recommended in high heat loss rooms, because like laminate flooring, you can most likely only heat your vinyl floor to 80°F to avoid damaging it. Check with the manufacturer what the recommended maximum floor temperature is and ensure you have a floor temperature sensor to keep the temperature no higher than what is recommended.
Be mindful of any liquid that spills on your vinyl floor, as this could easily seep through the seams and onto your UFH, short-circuiting it. If you see any spills, wipe them up immediately.
Laminate floors work better with wood and concrete subfloors. When installing your laminate flooring, make sure your subfloor is entirely stable and flat.
Test your UFH system 48 hours before laying down the flooring.
Before installing, unwrap the vinyl and lay it flat for at least 24 hours before installing it. Keep your room’s temperature between 65°F and 78°F. Wait at least 48 hours before switching on your UHF to ensure the adhesive has bonded sufficiently with the flooring and subfloor.
Many think that since carpet insulates, it will not be a good option for flooring for your UFH system, but it can work.
Carpet will take longer to heat up, but it will stay warm longer. A hessian-backed carpet, for example, can be used with your UFH since it doesn’t insulate too much compared to a rubber-backed carpet.
Before you have your UFH installed and plan to cover the floors with carpet, let your UFH supplier know, as this will make a difference in their calculations.
Your carpet mustn’t be too thick because this will prevent the heat from penetrating the room. Check the carpet’s tog rating, which is the rating of how well it insulates.
If you want to install carpet over your UFH system, its tog rating should be less than 1.5. It would be best if you also looked at the underlay’s tog rating. Preferably, it should be no more than 0.5, or your carpet and underlay should not have a tog rating of more than 2.5 combined so your UFH can still work efficiently.
If you have a felt underlay, we do not recommend you use a UHF.
Worst Flooring Options for Underfloor Heating
Rubber and concrete flooring are the worst options when it comes to UHF. It is also not recommended for flooring using an adhesive for joining.
Rubber is a good insulator but not a good conductor. Your rubber floor may take a long time to heat up and release the heat in the room.
It expands and contracts with temperature changes, and heat from your UFH system will affect your rubber floor. Aside from this, rubber tends to emit an unpleasant odor when temperatures are high.
UFH systems require layered flooring, so when installing, you can hide the tubing at the top layer, and since concrete is homogeneous, it is a bad choice for underfloor heating.
Swift temperature changes can also cause your concrete to crack, so temperatures need to be managed with more care compared to the other type of flooring discussed earlier.
Any flooring that uses adhesives as a joining system can have issues with UHF. High temperatures can cause adhesives to dry and loosen their hold.
If you need to use an adhesive to install your flooring to the subfloor, make sure it is a high polymer adhesive. High polymer adhesives are more resistant to temperature changes. The adhesive should also be highly flexible so it won’t be affected much by any subfloor movements.