You can have the best paint spray machine on site, but if the walls aren’t prepared properly, the finish will always fall short. Poor preparation leads to uneven coverage, peeling paint, and costly rework. Whether you’re spraying a new build, refurbishment, or commercial space, taking the time to prep walls correctly is essential for achieving a professional result.
At CES Hire, we’ve spent over 40 years supporting painters and contractors with reliable equipment and expert advice. This guide breaks down the key steps on how to prep walls for painting before using a paint spray machine.
Before any preparation begins, take a close look at the surface you’ll be spraying.
Check for:
Damp patches or staining
Flaking or peeling paint
Uneven or glossy surfaces
Identifying issues early allows you to fix them properly before spraying, preventing defects from showing through the final coat.
Any imperfections will be highlighted when using a paint spray machine, so repairs are non-negotiable.
Filling cracks and holes with suitable filler
Repairing damaged plaster or render
Sanding repairs flush once dry
Removing loose or flaking paint completely
Taking care at this stage ensures a smooth, uniform surface ready for spraying.
Clean walls are essential for good paint adhesion. Dust, grease, and residue can all affect how paint bonds to the surface.
Before spraying, you should:
Brush or vacuum walls to remove dust
Wash down greasy or contaminated areas
Allow surfaces to dry fully
This step is especially important in kitchens, commercial units, and refurbishment projects where surfaces may be heavily soiled.
Sanding helps create a consistent surface and improves paint adhesion.
Lightly sand previously painted walls
De-gloss shiny surfaces
Feather edges around repairs
Using the correct grit sandpaper will help avoid scratches while still providing enough key for the paint to bond effectively.
Paint spraying is fast and efficient, but overspray can travel further than expected.
Before you start spraying:
Mask windows, doors, and fixtures
Use painters tape on edges and trims
Lay protective sheeting or floor coverings
Good protection saves time on clean-up and prevents damage to finished areas.
Priming is often overlooked, but it plays a crucial role in achieving an even finish.
You should apply a primer when:
Painting bare plaster or drywall
Covering repairs or patches
Changing from dark to light colours
Spraying over porous or uneven surfaces
A suitable primer helps regulate suction and ensures the topcoat sprays evenly.
Wall preparation goes hand-in-hand with correct equipment setup.
The paint spray machine is clean and well-maintained
Filters and nozzles are suitable for the paint being used
Paint is mixed and thinned according to manufacturer guidelines
Reliable equipment and proper setup reduce downtime and help deliver a consistent spray pattern.
Knowing how to prep walls for painting is just as important as choosing the right paint spray machine. By assessing surfaces, making proper repairs, cleaning thoroughly, and protecting the surrounding area, you set yourself up for a high-quality, professional finish every time.
At CES Hire, we don’t just supply paint spray machines, we help you get the best results from them. If you need advice on wall preparation, equipment hire, or accessories for your next spraying job, our experienced team is ready to help.
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