Hi I am doing a kitchen diner knock through and I want underfloor heating with Karndean tiles. I would like a wet system on my existing combi but don't really want to excavate. I have looked at the polypipe overlay and the John Guest solution which have low profiles but don't know if they are suitable for Karndean. Has anyone used these systems in this configuration. Guessing you cannot tile direct on top of the boards but can you screed directly on them and tile on top? Any help much appreciated. regards Adam
Yeah that's the one, have a profile of about 18-20mm. My guess is you'd need 10mm ply on top then thin screed, then tile. So approx 30mm of floor.
Surface temp needs to be kept under 27°C 18 mm tung &groove chip board then a thin ply If you just ply it first you a get movement in the joints
Blimey that means 20mm board for the pipe, 18mm for the chip, 6mm for the ply, then the tiles that's 45mm!! That's no small increase in floor height!!
If there's boards going over the pipes system you won't need the chipboard some times there left bare with the pipes exposed that all
The backer boards that the pipes sit in come in different grades. A hard and softer type. If you get the one you can fit ceramic tiles directly onto you can latex over the top with a flexible screed then fit flooring. I've done this a few times. Check with the manufacturer and check the spec 1st. On one job the customer wanted an engineered wood glued direct to the system. The wood manufacturer said no, the adhesive manufacturer wanted a bit to test and the system manufacturer were as helpful as a chocolate ashtray
I've laid over a few of these. Last few it's had 12mm plywood on top the. I have used a fibre smoothing screed on top of the ply wood which has worked well. Where is the Wirral are you ?
