PREPARING THE HOLE
Cut a backblock from a scrap piece of plasterboard that is slightly narrower, but about 40mm longer than the hole. Push a nail through the centre of it, then apply some stopping compound to each end of the block.
Using the nail as a handle, slip the backblock through the hole, move it into position and pull it firmly against the rear face of the wall lining. Hold it there for about 30 seconds while the compound adheres to the wall. Leave it for about an hour until the compound has dried sufficiently to hold the backblock in place, then push the nail through the backblock and let it fall down behind the wall lining.
Using the 100mm broadknife, fill the hole with stopping compound, so it’s slightly overfilled. Remember to remove any excess compound from around the repair as it’s easier to remove it now while it’s wet than it is later when it has dried.
Because the compound in this repair is quite thick, it may take a considerable amount of time to dry – up to a couple of days in some instances, depending on ambient weather conditions. Don’t try and work on it before it’s completely dry as this will cause further issues later on.
When the compound has dried properly, scrape off any high spots with the broadknife and sand back if required.
Apply a second coat of compound. When the finishing coat is dry, sand back until smooth, then dust off before painting.
REPAIRING A BLEMISH
Blemishes, scrapes and scratches will happen to most plasterboard walls at some point. Moving furniture or children’s toys; are some of the ways that scrapes or scratches can appear in your wallboard, but they’re not difficult to repair.
Before starting, remove any paint chips or loose plaster, then sand around the area with 220 grit sandpaper to prepare the surface. Using a 75mm broadknife, apply a layer of stopping compound into the scratch, slightly overfilling the area. Make sure to remove any excess lumps of compound before they dry as it’s much easier to do this now than it is to sand it off later.
Once dry, the stopping compound can be sanded and then dusted off. If it’s a shallow crack, just one application of compound should be enough prior to painting, but deeper cracks may require a second coat of plaster before sanding back, dusting and painting.