How to paint walls like a pro

The complete guide to professional-looking results.

Painting walls is perhaps the most common DIY project undertaken by homeowners. It beautifies and protects surfaces, so it’s worth using the right materials and applying them properly. Just slapping on paint is not going to result in a room that looks professionally painted with a finish that lasts. The old adage that three quarters of any paint job should be in the preparation still rings true. Miracle products that do away with good preparation are rarely entirely satisfactory.

Painting an average-sized bedroom will take a weekend, allowing for drying time. You’ll need approximately four litres of acrylic paint for the walls and one litre of enamel for the trim. 


The range of paints available is huge, both in colour and choice of solvents and gloss levels. Most are oil- or water-based, but certain sealers are spirit-based. Bare in mind that flat finishes hide blemishes, whereas high gloss lets light reflect off every imperfection.

It’s easier to clean gloss, while just a gentle wipe on matt surfaces can leave a ‘polished’ patch. Paints for doors and windows need undercoat or sealer, but most ordinary wall paints can be applied directly. If you’re unsure of the best paint to use, ask your paint supplier for advice.

Gather your supplies

* Low Sheen paint for walls

* Enamel paint for trim

* Acrylic sealer/undercoat

* Oil-based sealer/undercoat

You’ll also need
Drop sheets; painter’s masking tape; methylated spirits (optional); sugar soap; wall filler; 120-grit abrasive paper; mineral turpentine; stain sealer (optional); 50 or 63mm brushes; medium nap roller; roller frame; roller extension; sponge; paint scraper; 6 in 1 painter’s tool; roller tray


Step 1
Painting is potentially messy, so begin by putting down a good cloth drop sheet – plastic sheets can be slippery, especially on polished floors. To make sure your drop sheet doesn’t slip, tape it to floor around perimeter of room.

Step 2
Remove curtains and blinds from windows, and any other brackets or pieces of hardware that could get in the way. If a piece of furniture is too large to move from the room, push it to the centre so it’s out of the way.

Step 3
Before you buy paint, it’s a good idea to establish what is already on the walls. It’s generally best to paint water-based over water-based paint, and oil-based over oil-based paint. There is an easy test. If you rub a dry finger over the wall, and paint comes away, then the wall is chalky or, in older homes, painted with kalsomine, which is an old lime-based paint. It must be washed off and the wall sealed with a binder to ensure new paint will stick. If your finger comes up clean, rub wall with a little methylated spirits on a rag. If rag shows colour, chances are the paint is water-based. If nothing comes off, chances are the wall was painted with an oil-based paint.

Step 4
Time to wash. Over years, walls accumulate grime and grease from people living in the home. Wash this off using sugar soap in water, but don’t make mixture too strong. Wipe walls with soap, then sponge off with a clean rag.

Step 5
Use scraper to scrape any loose paint. Fill holes and minor blemishes. If deep, they’ll take a day to dry, small chips and holes will take an hour or two.

Step 6
When dry, sand patches with 120-grit abrasive paper. Paint just the patches with acrylic sealer/undercoat or stain sealer. Paint over any pen marks with an oil-based or spirit-based sealer, so ink cannot bleed through final paint coats.

Step 7
If you have timber architraves and skirting, decide if you want to keep or paint them. If you want to paint, sand surface thoroughly to remove as much old finish as possible. Seal crack between trim and wall with a paintable gap filler.


Step 8
Before painting architraves and skirtings, use an oil-based primer/undercoat, to allow paint to adhere to timber and varnish. Now you’re ready to add colour. Always paint ceilings before walls and start both by ‘cutting in’ – use a brush to paint corners, cornices and anywhere a roller can’t reach. Also use brush to paint up to skirtings, architraves and windows. Before loading paint, wet brush and squeeze it out. This makes brush easier to clean later on.

Step 10
Pour paint into roller tray or work from the can. If using tray, keep top groove of tin clean with a brush so lid will seal when you finish. When putting paint on the brush, dip just 30mm of the bristles, or brush will tend to drip.

Step 11
You could use masking tape at the edges, but with a bit of practice and a steady hand, you’ll be better cutting in by hand and eye. Hold brush by wrapping your whole hand around it for better control. Apply paint to wall a little away from the line you are cutting into, then wiggle brush slightly so bristles and paint work their way to the line, all while moving brush in direction you are painting. Go over area a second or third time, until you’re happy, then move on. Complete all cutting in.

Step 12
Walls are best painted by rolling. Use a 5-10mm (medium) nap roller fitted to a frame. Add an extension handle so you can do the full wall without a ladder. Load roller evenly with paint by working it up and down paint tray. Spread evenly on wall, starting a little away from a cut-in edge at a slight angle and working back to it. Paint about 1m² at a time. When roller is just about out of paint, and while paint on wall is still wet, ‘lay off’ paint by rolling from ceiling down. Use a little pressure to blend paint and remove any local build-up that may run or leave ridges. Go straight to the next section, so edges stay wet and don’t show lap lines. Finish one wall at a time.

Step 13
Wrap and seal roller in plastic wrap or bag. Let walls dry. Add second and third coats as necessary. When dry, paint finishing coats on skirtings and architraves with oil-based enamel. Doing them last avoids spatter on the new surface. Again, you may need 2 coats.

Step 14
With painting finished, it’s time to clean-up. Use a 6 in 1 painter’s tool to scrape paint from roller back into paint tin. Keep paint for future touch-ups. Take roller and tray out to the garden and wash out with garden hose.

Step 15
Use several changes of water to wash out your brush in a bucket. Don’t wash paint down the sink. As you soaked brush first, paint should have stayed near tip of brush, making it easy to clean.

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