Ask the Pro: Misconceptions About Primer and How Many Coats of Primer To Use

February 12, 2021

Here on The Perfect Finish, we’ve shared what primer can do for your paint job, tips on choosing the right primer for your project and step-by-step instructions on how to prime various surfaces. In this post, we’re excited to turn the tables and talk about what primer is not – debunking seven common misconceptions about primer.

To discuss these often-believed myths and misunderstandings about primer, we sat down with John Golamco – Product Manager, Primers at KILZ.  A member of the KILZ team for over six years, John is a true expert on all things primer and has a wealth of knowledge to share. Ready to learn more? Let’s get rolling!

Misconception #1: Primer is just paint without color in it.

Although both primer and paint are classified as “architectural coatings” they are not the same. The formula of paint is different from the formula for primer. Paint is formulated to deliver color while primer is formulated to stick, better protect the surface, and in some cases block stains.

Misconception #2: Priming before painting takes too much time and won’t have a considerable effect my paint job.

Applying primer is indeed an additional step in the painting process but, depending on the surface condition and problem areas that might be present, investing in the primer step might actually save time and money. Applying primer to solve the problem (for example uneven, porous surfaces, strong colors or stains that might bleed through the paint, or adhesion issues that might cause peeling of the paint) before applying paint may prevent the need to re-paint or add several more coats of paint to get desired results.

Misconception #3: If I use primer over a stain and I can still see the stain through the coat of primer, the primer didn’t work. 

This is a quite common misconception about primer. A primer coat or coats is not meant to look like the finished topcoat paint. Primer is supposed to work underneath the paint to create a uniform surface, hiding strong or bright colors, block stains that might bleed through or show through the paint and enhance the paint’s ability to stick to the surface better and last longer. So even if the primer coat does not look like a fully painted wall, it will still perform the above functions. Then it is the paint’s job to completely cover the surface, deliver the color and look great.

Misconception #4: Primer is only for the walls. 

Primer is mainly applied to walls, but it is not only used for that surface. It can also be used on other vertical surfaces like wood paneling, brick or stone fireplaces or other masonry. Some types of primers are also designed to apply to horizontal surfaces like furniture, windowsills, floors and countertops. It depends on the type of primer and where it is designed to be used for – always read the label and follow label instructions.

Misconception #5: I’m using primer, I don’t need to clean the surface first. 

It is always important to properly prepare the surface before applying primer. At the very least, the surface has to be clean and free of dust, dirt and debris. Failing to clean the surface prior to applying primer may compromise the adhesion of the primer to the surface – which could lead to peeling and blistering.

Misconception #6: I need to add multiple coats of primer if I can still see my previous color. 

Depending on how strong or bold the previous color is, it may be necessary to apply more than one coat of primer. However, it is not necessary to over apply the primer with so many coats. As long as the primer applies uniformly over the previous color, then one or two coats should be sufficient. Again, it is not necessary to apply several coats of primer to try to get a perfect white finish. That is the job of the topcoat (paint) which has to be applied on top of the primer.

Misconception #7: I don’t need to prime when painting outside.

Priming outside is just as important, if not more important, than priming inside. Exterior surfaces are typically exposed to the elements and are subject to expansion (from heat) and contraction (from cold). This and the exposure to wind, rain, snow and even dust, dirt, pollution, sunlight (UV) may cause the paint to fail due to lack of adhesion to the surface. Using an exterior primer first on a properly prepared surface can make a big difference to whether the paint lasts or potentially cracks, peels or blisters after a short period of time.

Always remember to refer to our website kilz.com or product back labels for additional information on which primer is right for your project and detailed instructions on how to apply our products.