On Thu, 26 Jan 2006 08:12:12 GMT, Stuart Noble wrote:

I don't want to entirely waterproof the render, as it needs to breathe a
bit to clear any moistrure that does get in.

Moisture that gets in because it isn't waterproof you mean?

Not exactly, no. Moisture that gets in because its actcually got an airgap
behind it before its hits the marine ply skin of the house.
And a breatheable membrane so that any damp in the studowork structure can
breathe outwards as well.