The key to a good paint job? Properly prepping your walls

There’s nothing like a new coat of interior paint to make you feel good about your home and your life and, when it comes to painting, good results come down to prepping your walls.

There’s nothing like bad wall preparation and masking to make you feel crummy about the time and money you wasted getting bad painting results. That’s why every hands-on homeowner should know something about patching drywall and masking before ever picking up a paint brush.

If you do your own painting, wall prep skills are just plain essential. Paint applied to unprepped walls is simply a waste.


But even if you hire a professional painter, they’ll charge less if walls are in good shape before they arrive. Sometimes much less.

Wall prep and masking skills also let you fix up little dents and dings as they happen between paint jobs, staving off household shabbiness in a way that extends time between full-blown repainting campaigns.

Filling holes

Fixing drywall damage is all about filling holes and making repaired areas blend seamlessly with surrounding surfaces, and you’ll need four things for success:

  • A utility knife to trim away loose areas of damage;
  • A tub of spackling compound to fill the damaged cavity;
  • A spatula-like tool called a drywall knife to spread the compound; and,
  • A sanding sponge to smooth the hardened compound so it’s level with the wall.

The process of using these items is not unlike what dentists do to repair cavities and, like any good dentist, you need to make sure all the bad stuff is gone before filling begins.

Failure to remove all loose bits of paper and drywall before filling is the most common mistake I see beginners make. The trick is to get rid of everything — and I mean everything — that’s loose or extends above the surface of the wall before filling.

Frazzled paper, loose chunks of drywall and flaky paint —it all has to go. Fear of making the damaged zone larger is what causes beginners to be timid at this stage, but don’t worry. Filling is easy, no matter how much larger the damaged zone has become.


Blending in

prepping your walls Steve Maxwell sanding walls

When it finally comes time to fill the cleaned and enlarged cavity, remember two things.

First, swipe enough spackling compound into the cavity with your drywall knife so it rises slightly above the surrounding wall surfaces.


And second, when you do sand the damaged area after it’s dry, it’s vital that the edge of the patched zone taper smoothly and flawlessly with the surrounding wall. Allow any step-shaped zone between these two surfaces to remain and it will become painfully obvious after paint goes on.

Normally patched areas need to be primed to prevent new paint from peeling, but that’s beginning to change. The only spackling compound I know of so far that accepts new paint properly without priming is 3M Patch Plus Primer.

It’s quick drying, too, so it makes the prep process easier. It also maintains a consistent paint sheen in the patched zone after sanding — something that other spackling compounds I’ve used often fail to do.


Now for masking

prepping your walls Steve Maxwell masking tape

With your wall prepped, it’s time to think of masking areas where you want fresh paint to stop around trim, baseboards or areas of other colour.

As strange as it sounds, run-of-the-mill masking tape doesn’t really do a good job masking surfaces for painting. It actually takes a special tape to mask paint properly.


I’ve had the most experience with ScotchBlue Painter’s Tape, and it works well, but only if you apply extra pressure along the edges to seal the zone between tape and wall. That’s key.

Painter’s tape works so well thanks to a crinkle-free texture and well-behaved adhesives, but even still, it needs to be applied correctly to create crisp lines.

Follow this knowledge up with a careful paint job, and you’ll be amazed how much better you feel about your home and yourself.


About the Author

Steve Maxwell

Steve Maxwell

Steve Maxwell has been helping Canadians with home improvement, gardening and hands-on living since 1988. Visit for videos, stories and inspiration.



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