Tanking slurry - but to what height?

[SteWood]

Hi Folks

To comply with building regs I need to waterproof a room that I'm renovating that is slightly below ground (17 inches on one size, 5 inches on the other). I'm planning to use the product below. My question is: Do i need to tank all of the wall right up to the ceiling or just the bit that is actually underground (plus a small margin). I was thinking of tanking up to 25 inches. Does this make sense?

https://www.travisperkins.co.uk/Ka-Tanking-Slurry-25kg-Grey/p/185324

Regards
Steve

 

[tomfe]

If you are not adding another dpc then 1.5m about ground level. If you are upto the dpc. Rising damp normally goes to around 1m so to be safe add a bit.

 

[SteWood]

OK will do, thanks Tom.