Hello all, I am planning to install a built in thermostatic shower mixer.
The wall is a plasterboard/timber affair and after drilling some exploratory
holes I find there to be quite a big void in the centre between timbers. The
wall is about 5 inches thick

I think I may run into trouble on this one - what do I fix the valve to?
I'm thinking I may have to put in cross bracing timbers or maybe just use
the 15mm pipes as anchors.

Anybody done this or can advise best approach.

Many thanks