Been to quote on a job today and advice needed on this one I think!
50mt total area, 15mts is 22mm water-proof chipboard on joists screwed every 12 inches due to wet underfloor heating below. The rest of the floor is 35mts of new screed with wet underfloor heating. Tiles chosen are 600 x 400 x 15 moleanos white limestone with a 3mm grout line.
My worries are the chipboard not being up to the job, the lack of screws holding it down to the joists (although it does feel pretty solid ), the risk of the tiles cracking along the substrate joint and basically it all failing in 12 months! Builder has said he's done floors like this for 20 years blah blah blah and isn't happy she questioned him about it. The client has done some research and said she thought ply should have been used but the builder had already done it when she got home.
Now she's asking me the best way forward and I thought I'd ask you guys how you get round this before making any suggestions. Taking the chipboard up isn't really an option as its glues and screwed and won't be easy. Will Ditra solve the issues? I think I read on here a while ago Ditra do not recommend/guarantee their product on chipboard. No guarantee from them means I can't guarantee it either I suppose. Ply over the top? Cant screw it every 6 inches due to heating below so is it worth it?
Or shall I just pass on this one!!
Thanks in advance
50mt total area, 15mts is 22mm water-proof chipboard on joists screwed every 12 inches due to wet underfloor heating below. The rest of the floor is 35mts of new screed with wet underfloor heating. Tiles chosen are 600 x 400 x 15 moleanos white limestone with a 3mm grout line.
My worries are the chipboard not being up to the job, the lack of screws holding it down to the joists (although it does feel pretty solid ), the risk of the tiles cracking along the substrate joint and basically it all failing in 12 months! Builder has said he's done floors like this for 20 years blah blah blah and isn't happy she questioned him about it. The client has done some research and said she thought ply should have been used but the builder had already done it when she got home.
Now she's asking me the best way forward and I thought I'd ask you guys how you get round this before making any suggestions. Taking the chipboard up isn't really an option as its glues and screwed and won't be easy. Will Ditra solve the issues? I think I read on here a while ago Ditra do not recommend/guarantee their product on chipboard. No guarantee from them means I can't guarantee it either I suppose. Ply over the top? Cant screw it every 6 inches due to heating below so is it worth it?
Or shall I just pass on this one!!
Thanks in advance
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