Daily Telegraph


QThe plywood underneath my bathroom tiles has broken, and the looseness has spread under other tiles. Can I re-adhere the plywood to the floorboards with minimal effort? MA, BY EMAIL AThe tiles are delaminating from the plywood substrate. This is due to movement resulting from what could be a host of issues. In my experience, any efforts made to perform localised repairs to a moving tiled floor substrate are generally short-lived. In your case, and in the case of anyone wishing to lay floor tiles directly on to a plywood substrate, there are some key points to note and follow. The ideal method is to remove the floorboards and fix a 22mm marine plywood substrate directly to the floor joists at 200mm screw centres. Prior to adhering the tiles, it is also advisable to apply a PVA solution to improve adhesion and prevent against moisture from the adhesive mix being drawn into the plywood. Finally, in the case of both the adhesive and grout, a premix powder or flexible additive should be used. You could also re-lay the tiles on specifically designed interim layers. Nick Bizley co-founded, the London-based maintenance and refurbishment company