Hi All,

I'm in the middle of installing a corner shower in my downstairs cloakroom. I was hoping to tile the shower area but I've found some areas of wall plaster cracked and blown. The walls are internal 100mm aerated block (Thermalite type) with sand & cement render, finished with plaster skim. The cracks tend to be along the blockwork mortar lines both horizontally and vertically. In some cases the vertical ones are right through the centre of the blocks as well, but they do not appear in the room next door.

I'm wondering if I should replaster the blown areas or whether I could leave the walls as they are and tank them with a flexible liquid membrane like Mapei Mapelastic AquaDefense or similar.

Any advice would be much appreciated.

Cheers.

mmm I think the use of an Anti crack membrane come tanking membrane will be required.. Dural WP is one i use.. and is available at PHG Wetrooms.. link to the left<<<

If it is sand/cement render then you can skim the patches in with rapidset but you will need to prime the walls.

Originally Posted by Dave

mmm I think the use of an Anti crack membrane come tanking membrane will be required.. Dural WP is one i use.. and is available at PHG Wetrooms.. link to the left<<<

If it is sand/cement render then you can skim the patches in with rapidset but you will need to prime the walls.

Thanks dave,

Just one question though, is the product you suggest called Durabase WP or Dural WP. I can find Durabase WP but not Dural WP.

Thanks again.

both..lol.. depends who you get it off.. but Durabase WP is the one.. Waterproofing Membranes - PHG Wetrooms

Thermolites should never be rendered, there soft and liable to movement..

Originally Posted by whitebeam

Thermolites should never be rendered, there soft and liable to movement..

yeah i've only seen them used with dry lining