How to fill holes in walls

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Small cracks and holes can be irritating and ruin the finish of your paint job. Filling them isn’t too hard though, so here’s the easy way to do it.

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How to fill holes in walls

Before you can begin painting a wall, you have to carry out preparation and repairs so you have a smooth surface with a perfect finish. Whether you need to fill a hole in an exterior wall, cracks in your ceiling, or imperfections in plaster walls, here’s what you need to know.

How to fill hairline cracks in plaster

Hairline cracks in plaster can appear for a number of reasons. Subsidence is a main cause and is nothing to worry about, it’s just the natural settling of materials.

Cracks can sometimes indicate more serious damage. If you notice moist patches along the crack or that your wall is sagging or bulging, you should call a specialist to inspect the damage

Fortunately, hairline cracks in plaster can be covered up easily.

  1. Use a flat edged tool to get into the crack and loose materials.
  2. Use a flexible filler and fill the gap. Make sure you get into the gap and leave it to dry.
  3. Once the filler is dry, sand it down.
  4. Apply another thin layer on top of the crack and leave it to dry. Sand this down too.
  5. Apply a mist coat of paint (watered down paint) and this should blend in well with the rest of the wall, making the repair unnoticeable.

How to fill deep holes in wall

For deep holes, you’ll need a filler that works specifically for that depth as many are surface fillers. If you use a deep filler, this will make the job much easier.

  1. Clean the hole making sure you remove all loose materials. You can do this with the edge of a scraper or a fine brush.
  2. Use a flat edged filling tool to push the filler into the crack. You need to ensure it’s slightly raised above the surface of your wall so you can be sure it’s completely filled.
  3. Smooth it with a wet knife.
  4. Check the instructions to see how long it takes to dry – this should typically be around one or two hours. You will then be able to apply a mist coat over the repair.
  5. If you’re filling a particularly deep hole (more than 50mm deep) you’ll have to apply the filler in layers. Always be sure to wait for the first layer to dry before you apply another.

How to fill holes in wood

Many fillers are multi-purpose and can be used for walls and wood alike so you don’t have to buy a specialist product.
Filling holes in wood is a similar process to filling other surfaces but if the hole goes completely through the wood (like if you’ve removed a door handle, for instance), you’ll have to be careful.

  1. Fill the hole ensuring it’s raised above the surface. For a hole that goes all the way through, lay the wood on a flat surface before you fill it. Once you’ve filled it, prop the wood up and check the fill to see if there’s any gaps. If there is, top up the filler until it sits above the surface.
  2. Use a wet knife to smooth it out.
  3. Leave to dry.
  4. Sand down so the filler is now flush with the surface of the wood.
  5. You can now apply varnish or stain to your wood.

How to fill hairline cracks in ceiling

Ceilings are just as susceptible to movement as other areas of your home, so you might notice the occasional crack start to appear. Again, this is likely nothing to worry about but if you notice damp patches or sagging, you should call a professional to inspect the damage.

When it comes to the type of filler, you need to look for one that won’t sag or a specialist ceiling filler.

  1. Cover your floor and furniture with a dust sheet. The filler shouldn’t drip but it’s always better to be safe.
  2. Make sure the area around the crack is clean and you’ve removed any loose bits from the crack.
  3. Fill the crack enough to ensure it’s slightly raised above the flat of the ceiling.
  4. Use a wet knife to smooth it down.
  5. Wait for it to dry.
  6. Lightly sand the surface so the filler is now flush with the ceiling.
  7. You will now be able to add a mist coat so the repair will blend in with the rest of your ceiling.

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