How to Prepare a Wall

Walls act as the canvas for your vision of a room.

To make it easier to paint and ensure the colours appear as expected, it’s vital that interior walls are adequately prepared for painting.

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Estimated Time

Depends on wall size and the
amount of flaws it has.


Here's what you're going to need:

  • drop cloths*

  • bucket of
    soapy water

  • sponge

  • bleach

  • scraper

  • sandpaper

    180 or 240 grade
  • pre-mixed

  • gap

  • filling



  1. Remove any fixtures, such as picture hooks and light switch covers.
  2. Place drop cloths on floors and on any furnishings that must remain in the room.
  3. Wash walls with a soapy solution (a small amount of detergent in a bucket of water) to get rid of any dust. Rinse the walls to remove any traces of soap and allow time to dry. This means the paint will adhere to the wall, not the dust.
  4. If any mould is present, use a bleach solution to remove it from walls. Carefully apply the bleach solution to walls using a sponge and leave to soak for 15 minutes. Rinse thoroughly and again, allow them to dry completely.
  5. Assess the walls for any damage or surface lumps and bumps.
  6. If existing paint is peeling or flaking, scrape back the area to remove the loose paint, then gently sand the surface so no edges of the old paint are obvious.
  7. Fill any dents or nail holes in the walls with a premixed filler, using filling blades.
  8. Use acrylic gap sealant for cracks or gaps in areas where there may be movement e.g. near doors and windows.
  9. Once the fillers and sealers have set, sand down these areas. While you’re there, sand down any rough or shiny spots to improve adhesion and finish.
  10. Spot prime the filled areas with PPG Paints 3 in 1 sealer primer undercoat.
  11. To finish, apply painter’s masking tape to fittings which can’t be removed and any edges which may be fiddly and difficult to paint around, such as skirting boards and fixed shelving.
  12. Once your wall is prepped, you’re ready to get started. Let’s go paint!

Tips From ppg paints

  • For a really effective finish, apply a coat of PPG Paints 3 in 1 sealer primer undercoat to the entire wall. This allows for good adhesion and blocks out dark or existing colours, making it easier to paint over and providing a smoother, more professional looking top coat.
  • Remember you’ll need to add a few more materials to the list to complete this step.

    You will need
    • A 230 or 270mm paint roller frame
    • A matching roller cover with a 9-12mm nap
    • A matching paint tray; and
    • A roller pole

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