My question is two fold. Extension is being built, brickies have done first floor and now doing timber frame, this consist of 11mm osb sheaving board,, membrane, 25m batten and 18mm osb board. The intention is to attach EML and then lime render over that. Problem is this does not marry uup with extension wall below or existing wall. It has about 47mm. I was wondering about applying some more membrane, 25mm battens and either building outward with EML and render or carrier boards. In effect I would have four layers. Any views