I am tiling my bathroom floor: What plywood and adhesive to use with underfloor heating?

If you’re tiling your bathroom floor, why not give yourself an added luxury and install underfloor heating beforehand?

Here, we’ll look at what plywood and adhesive you can use with underfloor heating mats in your bathroom.

What plywood to use with underfloor heating?

The plywood you use beneath your underfloor heating must be WBP. This stands for Weather and Boil Proof and means your plywood will be able to get wet and dry repeatedly without delaminating.

However, you’ll also need to decide what depth you want the boards to be.

If you’re happy to rip up the existing floorboards, laying 18mm WBP plywood can be a good option. This will mean that the finished tile will be around the same height as the carpet where they meet at the door threshold.

Alternatively, if you’re going to overlay the existing floorboards then 9mm WBP plywood will likely be a better option. Always make sure to screw down the existing floorboards before installing your underfloor heating cable.

Follow our guide to installing underfloor heating to find out what to do next.

What adhesive to put on underfloor heating?

You can tile over your underfloor heating using a flexible adhesive.

There are several options but it’s best to use something that has a good deal of flexibility. Bal, Mapei, and Weber are all good brands.

Laying a filler or skim coat over the underfloor heating cable first will make it easier to lay your tile. Plus, it will help to ensure your floor warms up easily.

Make sure to use a flexible grout too, such as Bal Superflex.

Get the help of an expert

Unless you’re confident at DIY and have experience carrying out similar work, we’d recommend getting the help of an expert to install underfloor heating.

The materials you’ll need to use can all be expensive. And the last thing you want to do is risk having to pull up your newly-tiled floor to make adjustments and corrections.

Ultimately, paying a professional to complete the work for you will ensure that the job is carried out to a high standard that will stand the test of time.

Enter your postcode below to find a reputable installer near you.