"Matt Beard" wrote in message
oups.com...
I have seen plywood used in a number of bathrooms in place of
plasterboard when the wall is going to be tiled.

Is this a good idea?

What are the pros and cons?


Marine Ply, yes. Ordinary Ply, no. Plasterboard is more flimsy than
Plywood panels, and therefore more prone to movement, especially if it gets
damp. Plywood of the same thickness, or even slightly thinner, is more
rigid, but only if it is waterproof treated. Both ordinary Ply and
Plasterboard will hold water in the same way, so that's why you would use
marine Ply.

The other thing that Ply does better than Plasterboard, is when you drill
and fix things to the wall. Plasterboard has a tendency to break away
unless proper fixing techniques are used, and that usually means big holes
in the tiles to accommodate the fixing. Plywood, on the other hand, only
needs a small hole in the tile to allow a normal screw nail to get a grip on
the wood behind the tiles.

Cost wise, the Marine Ply is better for fixing, flatter and more rigid, but
is more expensive. Plasterboard is cheaper to install, but then you have
the disadvantage of having more expensive fixings, and it also has the
property of moving and swelling more than the timber backing.

The choice is yours mate. :-)