Help!: U/Floor Heating Mat on T&G Floorboards

[Oldman]

Hi, I hope you can give me some good advice.

I have an en-suite bathroom approx 2.5 x 2m. The floor is 28mm T&G timber boards on 225 x 60 joists. Ash deafening between the joists (old victorian house). This was laid about 20 years ago so should be stable.

I want to fit electric under floor heating mat then 300x300mm ceramic floor tiles over. Can I fix mat directly to T&G boards then SLC then flexible adhesive (perhaps Kerafloor with Isolastic?) + tiles or do I need to fit Hardie Board or similar. Raising floor level has knock-on problems to skirting, facings and door clearance. Also transition to next room.

I always try to do the correct job, no bodges so any advice will be gratefully accepted.

[Dave]

HI....

IMO you need to overboard first, but the boards must be stable and deflection free... then yes you can use Hardi type boards...

I'm afraid if you want UFH and a tiled floor then you will have to accept there will be a height build up..


Hope that helps.

[Oldman]

Thanks for the advice. I will change my specification and allow for extra height.

Merry Christmas!