Two Locations: 555 Bank St. - (613) 233-8441 | 1891 Merivale Rd. -(613) 695-2945

Do I Need Primer Before Painting Walls?

Do I Need Primer Before Painting Walls?

Rodrigo Pereira Teixeira |

One of the most common painting questions we hear at Randall’s is:
“Do I really need to use primer before painting?”
The short answer? It depends on your surface, paint type, and goals.

Primer isn't always required, but in many cases, skipping it can result in blotchy colour, poor adhesion, or premature peeling. Let’s explore when you need it — and when you might be able to skip it.


What Is Primer and What Does It Do?

Primer is a specially formulated base coat that:

           Seals porous surfaces

           Improves paint adhesion

           Blocks stains and odours

           Helps you achieve a more even, vibrant finish

Think of it as the glue between your surface and the topcoat.


When You Do Need Primer

You should definitely prime if:

1. You're Painting Bare Drywall or New Plaster

These porous surfaces will soak up paint unevenly. Primer seals the surface and ensures uniform coverage.

2. You're Painting Over Dark Colours

Going from navy blue to a soft white? Primer helps block the old colour and reduces the number of coats needed.

3. You're Painting Over Stains or Water Damage

Use a stain-blocking primer to stop bleed-through and odours.

4. You're Painting Glossy or Non-Porous Surfaces

Slick surfaces like tile, glass, oil-based paints, or laminated wood need a bonding primer to help paint stick.

5. You're Switching Paint Types (e.g. oil to latex)

If you’re painting over oil-based paint with latex, primer helps the topcoat bond and prevents peeling.

💡 Not sure if your walls need priming? Contact us — our experts can help you assess your space.


When You Might Skip Primer

Some situations allow you to skip the priming step:

           Walls already in good condition with a similar colour and finish

           Repainting with high-quality paint that includes primer-in-one (like Benjamin                 Moore Aura or Regal Select)

Even then, touch-ups or repaired areas may still benefit from spot-priming.


What Type of Primer Should I Use?

Choosing the right primer depends on your surface:

Surface Type                                     Recommended Primer
Drywall                                              Water-based latex primer
Wood (raw or stained)                      Stain-blocking oil- or latex-based
Glossy surfaces                                 Bonding primer
Masonry or concrete                        Masonry-specific primer
Water-damaged areas                     Shellac-based or stain-blocking

You can find all these in our paint collections.


Get Primed for Success at Randall’s

Whether you're painting a feature wall or an entire home, using the right primer can make all the difference.
Not sure where to start?
We offer in-store guidance, professional services, and a wide selection of top-tier primers and paints.


Helpful Links to Get Started:

           Contact Us — Ask a paint expert about your wall prep

           Painter Order Form — Order your supplies easily

           Services — From in-home colour advice to professional painter referrals

           Paint & Primer Collections — Shop trusted products from Benjamin Moore & more