It’s inevitable that houses get damaged. However, wall damage is a common problem. Knowing how to plaster walls can make your walls look great.
There are many reasons plasterwork can become damaged or worn out. Maybe some plaster (plasterboard), has been blasted or a bit of drywall (plasterboard), or someone has stepped on the ceiling and trampled around in the loft.
Guide to how to repair plaster walls
No matter how it happens, wall damage is unsightly and requires a lot of planning. These are my top plaster repairs in auckland to patch holes.
The right tools are essential for plaster wall repair (Philip Toscano/PA).
Plastering tips – the tools you need
- Pencil (when did you ever not need one?
- Spirit level
- If you are repairing a wall with studs, use a Stud detector
- Drywall saw (or padsaw)
- Tape measure
- A stiff brush (or a dustpan brush) is ideal.
- Soft brush – Anything larger than a 2 inch brush is fine
- 25x50mm Wood – Enough to frame your hole, if you are repairing drywall
- 40mm drywall screws
- Roll of scrim (course material, for when you are repairing a solid walls)
- Primer or PVA
- Plasterer’s trowel
- Repair plaster
- A few sheets fine sandpaper, 80-100grit
Time required: 2 hours
Determine which wall type needs to be repaired
This information applies to two types of walls. Stucco is applied to drywalling or plasterboard. So stud walls are hollow ones. They consist of a frame made of wood, covered with plasterboard sheets or plastered laths (thin wood strips that are nailed to studding). These holes are easy to fill but you will need to put new plasterboard in the hole before you can do any good work.
Solid walls are walls that are solid. They are usually made from brick or block and plastered with bonding plaster (or a stick sheet of plasterboard), before being topped with finishing plaster. These walls will not require any framing or plasterboard fitting, but they will require more than one layer plaster to repair.
How to repair plaster walls.
Before we fill in and smooth out the surface, we must fix the hole. This is for stud walls. To create a rectangle that matches the shape of the damaged area, use a spirit level to mark horizontal and vertical lines. Next, use a stud detector to ensure that there are no wires, studs or pipes in the area. Then cut the rectangle with a drywall saw. This can make it dusty so you should put a sheet on the ground before you start sawing.
After you cut the rectangle, you will need a tape measure. This will allow you to determine the depth of plasterboard you need to put back in. For wriggling in, cut your plasterboard to the exact size of the hole.
You will need to make a rectangular hole for the replacement plasterboard. Cut four pieces of 25x50mm wood to attach to the hole’s interior. The 50mm-wide wood should be visible 25 mm, and the remaining 25 mm should be attached to the plasterboard in the hole. As you screw into the wall, hold the wood in place and make sure to not screw into your fingers! After the four pieces have been positioned around the hole’s interior, screw the replacement rectangle of plasterboard onto the hole.
Tape a layer plasterer’s scrim around the edges of your hole. This will prevent cracks in the plaster from forming when it dries. Now you are ready to finish.
How to repair plaster walls and damaged solid walls
You will need a trowel and a brush to make solid walls. You should also make sure that you have a good sheeting, because this can cause some problems.
First, remove all plaster. Use a stiff brush to do this. The next step is to prepare primer. This primer can be purchased or made with PVA glue at a 5:1 ratio (water to PVA). This will prevent the dry wall’s damaged surface from sucking in all of the water. Let it dry and adhere to the wall. It should be applied liberally to the affected area.
You will need to use repair plaster if the damage is more than 5mm in depth. Premixed plaster is far more convenient than making plaster from scratch. Use your plastering trowel to scoop it out and press the trowel into the area. Continue to spread plaster until the hole is completely filled. This can be done by placing a spirit level or straight piece wood over the hole to ensure it touches the unaffected edges. Also, check that your plaster is not touching the surface.
Your trowel can be used to remove plaster from the undamaged wall surface. Leave it for around an hour to set up. To prevent crusty plaster from ruining the last stage, clean your trowel.
Repair of plaster walls
You are now ready for the final step of your repair, regardless of whether you have just plastered a small hole or placed scrim on your plasterboard patch. The same plaster can be used, but now you will feather it on the wall and spread it to nothing. You will first need to remove any wallpaper from the hole.
Next, scrub your repair with a soft brush. This is crucial for the final stage. A few specks in the plaster can drag on your work and cause damage.
Use a little primer to wet the surface (as explained above). Take a small amount from your tub and apply it to the surface. Spread the plaster along the edges of the damage. Spread the plaster thinly onto the wall surrounding the damaged area. This will make the joint disappear. You can accomplish this with patience and perseverance. Once the plaster has dried completely, you can sand off any ugly ridges. To prevent plaster from drying out around the edges of your repairs, use a damp brush.