Advice regarding backer board installation

[IHTRIQ]

Hi Everyone,

I have recently started the task of renovating the bathroom in my flat and am at the stage where I will be installing tile backer boards. In the end I went for a foam board kit made by abacus elements as they have positive reviews and it seems to be a pretty comprehensive waterproofing system. One thing that is not clear to me is do I need to leave a gap between the boards, floor and ceiling to allow for expansion/movement? Any advice would be much appreciated, thanks.

 

[AP tiler]

I wouldn’t worry much about it. You could leave a small gap at celing but wants to be tight to tray/tub so you can seal it

 

[AP tiler]

Defiantly no gap between boards no

 

[IHTRIQ]

Thanks for the advice, just finished installing most of the boards, hoping to finish the project before Christmas