Updated 29 October · 6 min read
PVC flooring with underfloor heating: what do you need to know?
Short answer
Yes, PVC and underfloor heating work well together, under four conditions. The manufacturer must certify that the floor is suitable. The floor surface temperature must stay below 27°C. Glue-down PVC flooring is the best choice. And with a new screed, the heat-up protocol must be completed first and the residual moisture measured.
Which PVC is suitable?
First check what the manufacturer states: not every PVC floor is suitable for underfloor heating. If it is suitable, the type of system still makes a difference.
- Glue-down PVC flooring (dryback). The best choice. The floor is thin and bonded directly to the subfloor without an air gap, so heat passes through efficiently. However, the subfloor must be fully levelled.
- Click PVC flooring and rigid core. Also possible, but only with an underlay approved by the manufacturer. The thermal resistance of the floor and underlay together must remain low, usually a maximum of 0.15 m²K/W, or whatever your underfloor heating supplier specifies.
Rigid core is more stable than thin click PVC flooring, but still expands and contracts slightly. Expansion gaps along the edges are still required, in accordance with the fitting instructions.
How warm can it get?
The deciding factor is the temperature of the floor surface: a maximum of 27°C, or lower if specified by the manufacturer. If it gets warmer, PVC can warp or develop gaps, which is not covered by the warranty.
- Your heating installer will set the water temperature to match that limit.
- A thermostat with a floor sensor prevents the floor surface from getting too warm.
- Do not lay thick rugs on PVC with underfloor heating: the temperature will build up underneath them.
- Does your system also have underfloor cooling? Check in advance: not every PVC floor may be cooled, and cooling can cause condensation.
New screed: complete the heat-up protocol first
A new screed with underfloor heating still contains a lot of moisture. Before PVC can be laid on top, the heating commissioning protocol must be fully completed. This is done by the heating installer or the contractor. After that, we measure the residual moisture using the calcium carbide moisture test. A handheld meter only gives an indication.
The limit depends on the type of screed and whether it contains heating. An anhydrite screed has a much stricter limit than sand-cement. We follow the requirements of the adhesive and flooring manufacturers. If the floor is still too damp, we wait. Fitting on a damp floor is the most common cause of adhesive failure.
Around the fitting day
- Before fitting: follow the instructions of the flooring and adhesive manufacturers for turning down or switching off the underfloor heating and maintaining the required room temperature.
- Acclimatisation: Follow the manufacturer's instructions for your chosen floor regarding acclimatisation, storage and temperature.
- Fitting: for glue-down PVC flooring, using an adhesive that is suitable for underfloor heating.
- After fitting: maintain the prescribed temperature for as long as the flooring and adhesive manufacturers specify. The waiting time varies by product.
- After fitting: gradually heat up the floor according to the manufacturer's schedule. We will give you this schedule on paper. A standard thermostat does not regulate this automatically.
Underlay and sound
No underlay is used beneath glue-down PVC flooring: the floor is glued directly onto the levelled subfloor. Beneath click PVC flooring, the underlay specified by the manufacturer is used. If the plank already has an integrated underlay, do not add a second one underneath; doing so can also void the warranty.
Do you live in an apartment with a VvE (homeowners' association)? Then an impact sound requirement often applies. There are sound-reducing underlays and systems that are also suitable for underfloor heating. We select a combination with a certified rating and provide you with the test report for your VvE.
Common mistakes
- Fitting before the heat-up protocol for a new screed has been completed.
- Measuring moisture with a handheld meter instead of the CM method.
- Click PVC flooring without an approved underlay, or with a thick, insulating underlay.
- Turning the heating up full immediately after fitting.
- Letting the floor surface get warmer than 27°C.
Frequently asked questions
Can any PVC floor be used with underfloor heating?
No. Only floors that the manufacturer certifies as suitable for underfloor heating. This is stated in the product's technical specifications; we will include it on your quotation.
How warm can a PVC floor get?
The floor surface must not get warmer than 27°C, or lower if specified by the manufacturer. Your heating installer will set the water temperature accordingly.
Click or glue-down on underfloor heating?
Glue-down PVC flooring is the best choice: thin, with no air gap, so the heat transfers well. Click PVC flooring is also possible, but only with an underlay approved by the manufacturer that has a low thermal resistance.
Does the underfloor heating need to be turned off during fitting?
Follow the floor and adhesive manufacturer's instructions for turning down or switching off the underfloor heating. Maintain the prescribed room temperature. The waiting time after fitting and the gradual reheating process also depend on the chosen product.
Can PVC be fitted on a new screed with underfloor heating?
Yes, provided the screed's heat-up protocol has been fully completed first and the residual moisture is low enough. We measure this using the CM method before we begin fitting.
Unsure about your floor and heating?
Telephone advice and video consultations are free of charge. For an on-site evaluation and moisture test, we will schedule an on-site assessment. An on-site assessment is free if you purchase the floor from us. If you decide not to go ahead with us, the visit costs €150.