
It’s tempting to skip the extra expense of primer when you’re doing some remodeling and painting in your home. Skipping that addition to your checkout bill could lead to regret later.
What Is Paint Primer?
Primer is an essential first step in painting many things, but especially things you commonly paint around the home like walls, wood trim, and other surfaces. While primer formulations can vary, they’re generally a combination of synthetic resins, solvents, and polyethylene, a type of plastic, to increase durability.
The purpose of the primer is right there in its name: it primes the surface for painting. The primer seals the surface, which both makes the paint adhere better and requires the use of less paint. Not only does that save you money on by decreasing the amount of paint you need for the project, but continues to save you money and time into the future by ensuring the job lasts longer.
When to Use Primer
There are many times when it is important to use primer when the use of this extra step and investment makes a huge difference in how well your new paint job turns out. Consider priming when you’re:
Painting Over a Darker Color
If you’re painting with a lighter color over a darker one, you’re going to be painting for a while. The dark color underneath will affect the look of that lighter shade—unless you use a primer. When dealing with dark paint underneath, a tinted primer (in a shade that is lighter than your new shade) is even more useful.
Painting Over Dirty or Damaged Walls
If your walls, or whatever you’re painting, has any kind of flaws, whether that’s oil staining or mildew, a good primer will help keep those damaged spots from showing through your fresh, new paint job. Look for a primer that is designed to help cover such damage—look for primers with stain blocks and mildewcides, depending on your need.
Painting Over a New Surface

If you have freshly drywalled your wall or you’re painting over bare wood, primer is a must. The primer coatings fill the pores in wood and drywall so that your paint will adhere better. Bare wood and drywall is tremendously “thirsty” and you’ll burn through your paint quickly applying multiple coats if you don’t prep the surface with a primer. Use a metal primer when painting over metal, and also use primer when painting over plastic.
Using Latex Paint Over Oil-Based Paint
Latex and oil paints don’t mix—if you’re painting over old oil-based paints and you want your new paint to stick, you’ll want to use primer in between. Without a primer, the latex paint won’t bond properly to the cured oil paint and will easily peel away if damaged. There are primers made to work with both types of paint, so ask for some help in the paint department on picking the right one.
Painting Over Wallpaper
If you’re painting over wallpaper or you’ve removed the old wallpaper and have to paint over the residual glue, a primer will help smooth things out and make your paint get better coverage over any color of the wallpaper. Painting over wallpaper is tricky though, and we recommend doing a fair amount of reading on the topic first before committing to the project.
When to Skip the Primer
There are a few times when you can bypass primer. If you’re painting over the same type of paint with a similar color and there are no stains to deal with, you can leave the primer behind. You can also buy paint that has the primer in it to give your repaint project a little boost.
Before you start any paint job, be sure to inspect what you’re working with. Take some time to give the walls a good scrub down, too! Primer or not, a clean surface is essential for good adhesion.