How To Paint Breeze Blocks
Bare blockwork in a garage or garden soaks up paint fast so the prep and the paint you pick make all the difference.
The short answer
To paint breeze blocks, brush or wash the blocks clean, fill any cracks, then seal the porous surface with a masonry primer or a thinned first coat of masonry paint. Once that's dry, cut in the edges with a brush and roll on two coats of masonry paint with a long pile roller, choosing a dry, mild day for outdoor walls.
Breeze blocks turn up everywhere, from garage walls and garden walls to extensions, outbuildings and decorative screens on a patio. Left bare they look unfinished, and painting them is a job most people can tackle themselves. The catch is that blockwork is rough and porous, so the paint you choose and the prep you do decide how the finish looks and how long it lasts.
Can You Paint Breeze Blocks
Yes, breeze blocks take paint well once they're clean and sealed. They're made from concrete or cement mixed with aggregate, which leaves an open, sponge-like texture. That texture drinks the first coat and gets through more paint than a smooth plastered wall. On a dusty or unprimed surface, the paint struggles to bond at all.
The name covers two kinds of block. Plain building blocks are the grey, rough-faced ones you see in garages and garden walls. Decorative breeze blocks, also called screen blocks, have patterned cut-outs and are used for feature walls and garden screens, like the white blocks in the photo further down this page. The method is the same for both, but the decorative ones need more brushwork.
The Best Paint For Breeze Blocks Inside And Out
Masonry paint is the right choice for breeze blocks, especially outside. Its binders are made to grip concrete and cement and to stand up to rain and frost. Both the smooth and textured versions in our guide to the best masonry paints for brick and render suit blockwork.
Inside a garage, workshop or utility room, you can also use emulsion on breeze blocks. Expect it to take at least two coats over a primer, and only use it on indoor walls, as standard emulsion isn't made to cope with the weather. Masonry paint can be used indoors too, though its smell lingers more in an enclosed space, so keep doors and windows open while it dries.
How To Paint Breeze Blocks
The job breaks down into four stages. Give each one the time it needs and the paint will go on more easily and last far longer.
1. Clean And Repair The Blocks
Start by getting rid of dust, cobwebs, moss and loose bits of mortar with a stiff-bristled brush. On outside walls, a pressure washer for walls and patios shifts dirt and green growth quickly, but the blocks soak up water and need several dry days before you paint, so plan for that.
White powdery deposits on new blockwork are salts working their way out of the block. Brush them off dry and wait to see if they come back before painting, as paint over active salts will bubble and flake. Fill cracks and holes with an exterior-grade filler for cracks and holes or a masonry repair mortar, and let the repairs dry fully.
Finally, protect anything you don't want painted. Lay dust sheets along the base of the wall and run good masking tape along window frames, door frames and fittings, as rolling rough blockwork throws out a fair bit of spatter.
2. Seal The Surface With A Primer
Bare blocks are thirsty, so a first sealing coat stops the finish coats soaking straight in. Use a masonry primer or stabilising solution, or thin the first coat of masonry paint with water as the tin directs. Brush or roll it on evenly, working it into the texture, and leave it to dry completely.
Blocks that have been painted before and are sound don't need priming. If the old paint is chalky when you run a hand over it, a stabilising solution helps the new coat stick.
3. Cut In And Roll On The Paint
Use a stiff masonry paint brush to cut in along the top of the wall, around the edges and into the mortar joints. Then cover the faces of the blocks with a long pile roller for rough surfaces, which pushes paint into the pits and hollows that a short pile sleeve skims over.
Work in sections a few blocks wide, from the top down, and apply two coats for an even colour. Hold off on the second until the first is dry to the touch, going by the drying time on the tin rather than guesswork.
4. Pick The Right Weather For Outside Walls
Outside, the weather has as much effect on the finish as the paint does. Avoid painting if rain is forecast before the paint has had time to dry, and steer clear of frosty mornings and cold evenings, when paint struggles to dry and cure. Hot sun on the wall is just as bad, as the paint dries too fast and leaves a patchy finish with visible lap marks, so follow the shade round the building through the day.
Choosing A Colour For Breeze Blocks
The right colour depends on what the wall does. A garden or retaining wall looks best in a shade that sits quietly with the house, so soft greys, stone and off-whites are safe picks that match render and paving. A garage or workshop wall inside benefits from white or a pale grey, which bounces light around and makes the space feel bigger.
Decorative screen blocks are where you can have more fun. White shows off the pattern of the cut-outs and looks crisp against planting, while a bolder colour turns a patio screen into a feature. Our guide on choosing paint colours has more tips on testing samples before you commit.
Painting Decorative Screen Blocks
Patterned breeze blocks take longer than a plain wall because every curve and opening needs paint on the inside edges. A small roller covers the flat faces quickly, as in the photo above, but keep a brush to hand for the returns and corners of each cut-out. Work from one side of the screen to the other so you don't miss the inner faces, and check from both sides of the wall before you pack up.
Our Advice Before You Start
Breeze blocks aren't difficult to paint, but they use a lot more paint than you'd expect because of how porous they are. Buy enough masonry paint for two full coats plus the sealing coat. And don't be tempted to skip the cleaning and priming, because that's what stops the finish flaking after the first winter.
More Questions Answered
Do you need to prime breeze blocks before painting?
Bare breeze blocks need priming before painting because they're porous and soak up the first coat. A masonry primer, a stabilising solution or a first coat of masonry paint thinned with water seals the surface so the finish coats cover evenly. Blocks that are already painted and sound can be painted without priming.
Can you use emulsion on breeze blocks?
You can use emulsion on indoor breeze blocks, such as garage, workshop or utility room walls, but not outside. Prime the blocks first and allow for at least two coats, as the rough surface soaks up paint. For outdoor walls, use masonry paint, which is made to cope with rain and frost.
Should you paint new breeze blocks straight away?
New breeze blocks and fresh mortar need time to dry out before painting, as moisture trapped in the wall pushes salts to the surface and causes the paint to bubble or flake. Brush off any white powdery deposits, wait to see if more appear, and only paint once the wall is dry and the deposits have stopped.
What roller is best for painting breeze blocks?
A long pile roller is best for breeze blocks because the deep fibres push paint into the pitted, open texture of the block. A short pile sleeve skims over the surface and leaves pinholes. Use a stiff brush for the mortar joints and edges, and a small roller for the faces of decorative screen blocks.
How much paint do I need for breeze blocks?
Buy enough masonry paint for two full coats plus the sealing coat. The open, sponge-like texture of the blocks soaks up the first coat, so you'll get through more than you would on a plastered wall of the same size. A proper sealing coat stops the finish coats disappearing into the block and keeps the amount you need down.
What's the white powder on new breeze blocks?
The white powdery deposits on new blockwork are salts working their way out of the block. Brush them off dry and wait to see if they come back before painting, because paint over active salts bubbles and flakes. Once the powder stops returning, fill any cracks and move on to the primer.
Can I pressure wash breeze blocks before painting?
A pressure washer shifts dirt and green growth from outside breeze block walls quickly. The blocks soak up water, though, so they need several dry days before you paint. Plan for that gap and check the blocks have dried fully, as paint on damp blockwork won't grip properly.
What's the best way to paint decorative screen blocks?
Use a small roller for the flat faces and keep a brush to hand for the returns and corners of each cut-out. Patterned blocks take longer than a plain wall because every curve and opening needs paint on the inside edges. Work from one side of the screen to the other, and check from both sides before you pack up.
Eddie spent five years as a self-employed painter and decorator before going part time to become one of the main writers at DIY Works. From garden fences to mist coats on fresh plaster, painting and decorating is his speciality.