dcochran

Hi Thermo, Thanks for the quick response, I'm retaining, part top soil, part light clay, part heavy clay (1/2 the wall at some points). My only concern about not putting a membrane or dpm behind the wall was that the water would seep through the wall and discolour the sleepers making ugly stains. I also have read some articles about building sleeper walls and they all suggest using some kind of dpm so not quite sure which way to go here ?

Thanks Again.
Darren

what sort of soil are you on?
a sleeper wall is not like a masonry retaining wall. By its nature its free draining and will allow water to pass through it. Theres no real need for the drainage pipe unless you are on heavy clay. If you are i would backfill with shingle behind it. You certainly dont want to be putting any sort of membrane or dpm behind it, the wall needs to be able to breath. Hope that helps