How to undercoat a wall

nareele short
View the video

How to undercoat a wall

View the video
×

Project Overview

When it comes to painting, preparation is the key. That’s why it’s important to apply an undercoat, especially on a new wall. An undercoat provides a layer for paint to adhere to, makes a surface flatter, fills in the grain and can even be used to seal in stains. Continue to step-by-step instructions
paint keep clean
View the video
00:24
×

How to keep a paint can clean and avoid sticking

Trying to pry open a paint can lid that’s stuck can be frustrating. To solve this problem, you have to stop any paint from getting into the lip of the can. A quick and easy way to do this is with a coathanger. Simply measure the width of the can and cut the bottom of the hanger a bit longer with some pliers. Then, bend the ends of the wire over the edge of the can. Now, when you dip your brush, you can wipe the excess paint onto the wire and keep the lip grooves free of paint. And if there’s no dried paint in the grooves then the lid will be easier to get on and off.

Step by Step Instructions

1 Protect the floor
2 Prepare the walls
3 Clean the wall with a damp cloth
4 Cut in the undercoat
5 Paint with the roller
6 Remove the masking tape
7 Job done
  • Step 1. Protect the floor

    To protect the floor from getting undercoat onnit, stick masking or painters tape where the wall meets the floor. Then lay drop sheets on the ground.
  • Step 2. Prepare the walls

    Before you paint it’s important to make sure that your walls have been prepared. Older walls need sanding or old bits of flaking paint to be scraped off. Fill any cracks and gaps with filler. Let it dry and then sand it back again. When you’re sanding, use a fine grade sandpaper, such as 120 grit. With your dust mask and safety glasses on, hand sand for small areas or, for larger areas, use an orbital sander.
  • Step 3. Clean the wall with a damp cloth

    After sanding, wash the wall thoroughly. The undercoat won’t stick to the wall if it is dirty. We used water and sugar soap to clean our walls, then let the wall dry.
  • Step 4. Cut in the undercoat

    Use a paint brush to cut in areas that are too tight for rollers to paint such as corners of the walls and where the walls meet the floor. It’s a good idea to do this before putting on the skirting boards.
  • Step 5. Paint with the roller

    After you’ve finished cutting in, use a roller to paint the rest of the wall. Use an extension pole with your roller to make the job easier to reach high places. Work in small zones, about one square metre at a time for a great finish.
  • Step 6. Remove the masking tape

    An hour after painting, peel the masking tape off slowly, holding the end at a 45-degree angle away from the wall. Don’t wait until the undercoat is dry because the undercoat may crack and lift when you peel the tape off.
  • Step 7. Job done

    Now that your undercoat is complete, you’re ready to apply the top coat.

Tools and Materials

Tools

  • Drop sheet
  • Dust mask
  • Extension pole
  • Filling knives
  • Ladder
  • Masking tape
  • Orbital sander
  • Paint brushes
  • Paint rollers
  • Paint scraper
  • Paint stirrer
  • Paint tray and disposable liner
  • Sanding block and float

Materials

  • Disposable gloves
  • Filler
  • 80 grit and 120–180 grit sandpaper
  • Sugar soap
  • Undercoat
diy bookcase 03:22

Shelving & Storage How to build a D.I.Y. bookcase This D.I.Y. bookcase might be the perfect solution for your storage needs. It’s easy to make and its minimalist look will suit almost any room. Find out how with Bunnings.

bedside 02:54

Bedroom D.I.Y. copper and timber bedside table This copper bedside table will add a modern touch of style to your bedroom and it is easy to make.

closet and storage ideas

Bedroom Cut the clutter with a closet clear out Cut the clutter with these expert storage tips to help you get more from your wardrobe.

How to update window mullions 02:04

Bedroom How to update window mullions It may not be in your vernacular just yet, but a window mullion is the aluminium that holds your window to its frame! They’re super easy to update, just follow these steps and they’ll look good as new in no time.

Copper Jewellery Stand 02:02

Bedroom D.I.Y. copper jewellery stand Keep your jewellery all in one place with just a few spare plumbing parts and a bit of timber. You can make this stylish copper jewellery stand. Read more at Bunnings.

Person attaching the drawer handle 06:02

Bedroom How to assemble a wardrobe insert unit Learn how to assemble a shelf and drawer unit for a wardrobe. Just follow our step-by-step guide.

Man measuring the position of the water pipes 02:25

Laundry How to install a laundry cabinet Learn how to measure and fit a laundry cabinet. We’ll show you how to cut holes for pipes and drainage and attach the cabinet to your wall.

Workspace

Study A workspace fit for any room Whether you need a nook to do family admin or a room for running your fledgling business empire, it’s possible to carve out a great workspace in any home.

low water garden

Planning & Projects How to create a low-water garden ‘Dry’ or ‘low-water’ gardening is a real art and, when done right, will provide you with an inviting landscape that uses very little water.

Finished artificial green garden wall behind garden bench 02:05

Planning & Projects How to create a green wall using artificial hedge Green walls are all the rage at the moment, but buying and maintaining one can be costly. Why not have a go at creating your own using pieces of artificial hedge – it looks great and will last the distance. Here’s how.

reducing water

How To Save Water How to reduce water usage Whether indoor or outdoor, there are lots of ways to be smart about water usage. And there are some simple actions that can make a big difference to your water bill.

doorbell 02:04

Doors How to install a ring doorbell The Ring video doorbell is a wireless doorbell which allows you to see who is at your front door. Find out how to install the Ring video doorbell yourself.

a tree lit up with solar lights around it 01:46

Garden Lighting How to install solar lights in your garden Solar lights are a great way to illuminate your pathways and highlight your garden beds at night. Install them yourself with these easy steps.

how to organise your pantry 02:52

Shelving & Storage How to organise your pantry Create an organisational system in your pantry with these handy storage hints. Trust us – its life changing!

front door 01:31

How To Paint How to paint your front door Make an entrance every darn day of the week by painting your front door a bold, enticing colour!

how to hang pictures

Walls The best way to hang pictures on a wall Learn the tricks to hanging your wall decor so it looks good – and doesn’t damage the plasterboard. Create an effortless-looking display by taking the time to consider spacing, proportion, frame styles and colour palettes.

Health & Safety

Please make sure you use all equipment appropriately and safely when following the advice in these D.I.Y. videos. You need to be familiar with how to use equipment safely and follow the instructions that came with the equipment. If you are unsure, you may feel it is safest to consult an expert, such as the manufacturer or an expert Bunnings Team Member.

Grave health hazards are linked to asbestos, which may be in homes built up to 1990. Health hazards may result from exposure to lead-based paints in older materials and copper chromium arsenic (CCA) treated timber. For information on the dangers of asbestos, lead-based paint and CCA treated timber and tips for dealing with these materials contact your local council's Environmental Health Officer or visit our Health & Safety page. You can also use a simple test kit from Bunnings to indicate the presence of lead-based paint.
Top of the content