Waterproofing cement board

[theflyingpig]

Having thought I was Dr doing the right thing by fixing 12mm cement board to stud walls where shower / bath is going to be, I'm now not so sure!

The more I read about cement board the less I like it....

I assumed it was waterproof.... Turns out I now have to tank it...

What with? A tanking slurry? An expensive tub of 'liquid membrane'?

Why is nothing at simple?

 

[RandomGrinch]

I assumed it was waterproof....

It has always been 'water resistant'!

An expensive tub of 'liquid membrane'?

Not that expensive, considering the cost to put things right after continual leaks.

I've used this stuff and it's great...

Mapei Shower waterproofing kit | DIY at B&Q

This kit is suitable for commercial & domestic showers.

www.diy.com

 

[theflyingpig]

Thanks, I think I'll go with that mapei stuff - I've always found their adhesives and grouts to be really good....

 

[theflyingpig]

Do you think the primer supplied with that kit is '"primer g"?

 

[drives]

Nothing wrong with cement board and tanking kit. Presumably with backer board you’d need to waterproof the joints anyway.

I used the tile master tanking kit which is around £50. Photo attached of what we ended up with. I’d steer clear of the everbuild one which I used for another shower area. I found the consistency nowhere near as good- a bit lumpy from what I recall.