Bathroom floor buildup

[Vijay]

Morning,

 

I need to build up the bathroom floor to meet the walk in shower former edge. The edge of the former is 30mm high and I assume around 5mm of adhesive under it. The whole floor will be tiled.

 

There's no UFH, would I still need to use a decoupling (ditra) mat? It's not the largest of rooms, probably around 4m2 (6m2 less 2 odd for the shower and fitted furniture). Or would I just be able to primer the ply and then use flexible adhesive which is what I'd have done in the past?

 

So I have approx 35mm to build up to the former. I was planning on 18mm ply down on top of the joists which then leaves me 17mm to build up. I could batten up the joists or add extra boarding? Any suggestions?

 

Cheers

 

Vijay

[nod]

Usually the easiest way if you already have flooring down Would be to bed a fibre tile board onto adhesive Normally 8 mil 5-10 adhesive  No decoupler needed 

When tiling your adhesive should be the same thickness as your tile 

[Vijay]

The floor at the moment is a mix of OSB and floorboards (which have seen better days). So I planned on replacing the floor around the shower former with all new.

 

So 18mm ply,  then 5-10mm adhesive (any screws or mechanical fixings at all?), then 8mm fibre tile board?   That would give me the the 35mm lift if I used 9mm adhesive.

 

Not yet confirmed but the floor tiles were 9/10mm, I didn't think I would need 10mm of adhesive under them, why so thick??