We recently replaced our AC unit and the new one is a bit smaller than than the previous unit - which has left a large piece of cardboard looking plaster. Not sure if I cut it out and patch it or just put a bit of plaster compound over the top?
Hello @MPhan
Welcome to the Bunnings Workshop community. It's sensational to have you join us, and thanks for sharing your question about your plaster wall.
The cardboard looking section is your plasterboard wall unpainted. I recommend using https://www.bunnings.com.au/selleys-180g-spakfilla-rapid-gap-filler-180g_p1231864 to fill in any cracked or damaged sections of the wall. I suggest sanding the edge of the unpainted section along with the repaired sections so that it removes the high edge of the paint. You should end up with a smooth surface where the painted section and the unpainted section are level. I recommend wiping the surface with https://www.bunnings.com.au/selleys-sugar-soap-wall-cleaning-wipes-25-pack_p1210330 to remove all the sanding dust.
I then propose using https://www.bunnings.com.au/dulux-1l-1step-prep-primer-sealer-undercoat_p1370232 and the https://www.bunnings.com.au/dulux-500ml-vivid-white-low-sheen-wash-wear-interior-paint_p0638834 for the topcoat tinted to the colour of your wall. In order to get a colour match, I suggest cutting a small sample of your wall colour at least the size of a one-dollar coin. You'll need to patch this cut section and paint over it as well.
Here is a handy guide: How To Paint A Wall Or Room
Please remember to wear personal protection such as gloves, goggles and a mask.
If you need further assistance, please let us know.
Eric
Hi @MPhan
Also remove the loose parts where the surface has been blown out like around the hole adjacent to the lower left of the AC unit and then fill over that as the plaster behind the cardboard covering of the plasterboard has seperated from the rest of the board and if you try to fill over that, there will be instability of the surface in that area.
