Using wood to fix a plaster wall!!

[Silverlining]

My husband has had the wonderful idea to use wood to repair some largish holes (e.g. 22cm x 10cm) in his office wall caused by enthusiastic electricians fishing for wires. I guess he will use something to fill the gaps between the plaster and lathe parts of the wall, and the wood. He is intending to fix the wood pieces to studs. This seems nuts to me, but my current arguments (that I have never seen someone do this,and that the drywaller we once had just cut drywall to size and mudded to fit) isn't flying. Can someone tell me why my intuition (this is nuts) is right?

thanks!

[The3rd Earl Of Derby]

You leave it up to hubby,because you're all muddled. ;-)

[The Natural Philosopher]

The way I usually do this is to use bits of newspaper stuffed in the holes, and then scrap plasterboard jammed in, then slap plaster type filler over the top, and finally take it all back to smooth with an orbital sander.

[Lobster]

Can you clarify what he's going to do with these wood pieces, and what's going to be plastered, etc?

David

[Silverlining]

He intends to use these flat wood pieces to fill in several holes in the plaster and lathe walls. The holes vary in size from relatively small (5x8) to larger (22x15). I believe he intends to try to make some holes larger so he can have the wood attach to two studs. He is then likely to use polyfilla to fill in the gaps between the wood (it's actually 5/8 plywood) and the original plaster and lathe.

Can you tell me why he SHOULDN'T do it this way (or if he shouldn't!), and what the ideal method is for a DIYer who doesn't want to do a bodge job?

Thanks for any help!

[Rob Morley]

You're right, he's wrong - that's just the way it is (surely as a woman you're used to this by now?)

[Phil L]

If he uses sheet wood of any kind, the plaster will not bond to it, if however he cuts new laths from any scrap timber and nails these on, he can plaster it as normal, (once he's stripped back to the studding of course) I suggest 'Gyproc Bonding' or 'Brownin' for the base coat and multi- finish for the skimming, skimming over browning or bonding should be done on the same day...once dried it is almost impossible to skim to a decent finish due to it's absorbency.

Even the thinnest plasterboard would probably be too thick and the bumps would be noticable.

[The Natural Philosopher]

Only slight downside is that wood moves as the humidity changes and its likely you will get crack lines appearing in the skim coat..

That's why its best to use plaster supported on whatever substrate you can find - balled up newspapers is always good ;-)

[marble]

Good advice but I'd use "bonding coat" not browning which isn't grippy enough for this IMO . Also as an alternative to using wooden laths, use expanded metal lath.