DIY Doctor UK DIY Forums

we have recently pulled up some old laminate flooring in our kitchen and found that there had clearly been a flood of some sort because there was a large area of blackness and dry rot. we've had a preservation firm in to treat the area and also replace some worn out floor boards. i now need to lay plywood down and tile the floor.

my questions are -

a) what thickness of plywood should i lay down to ensure that no movement occurs beneath the tiles? should i screw or nail the plywood? and how far between each nail/screw?

b) should i lay a damp proof / waterproof membrane beneath the plywood to avoid any further damage from flooding via washine machine etc?

Hi,

Use at least 18mm WBP plywood, screwed every 150mm.

A membrane would be of no use as the screws would puncture it.The WBP is any exterior ply which is water proofed.

Also use a flexable adhesive when laying the tiles and use water proof grout. Silicone the edges and this will then make the surface waterproof. :)