Ever wondered WHY you need primer for your painting projects? This guide to primer will explain what primer is, different types of primer, and how to use it.
If you have ever painted a wall in your home or helped a friend, you’ve likely used primer. It’s a MUST HAVE for DIY’ers and it’s important to understand why and WHEN to use it. If you plan to do a lot of DIY projects, it’s helpful to always have a 5 gallon container on hand.
What is Primer?
Primer is a type of paint that is applied to a surface before the intended paint color or finish is applied. Primer is one of the biggest factors that can make the difference between a poor or a so-so paint job and a professional-looking one.
While you may have seen paints that claim to have primer included (they’re advertised as “paint plus primer!”), these paints aren’t true primer. Those types of “primer” are useful for painting walls in situations where there’s a dark color that you’d like to cover because they require fewer coats of the paint, but using primer is simply a cheaper and easier alternative.
Using plain primer on a project before finishing with a paint helps you cut costs.
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Different Types of Primer
Latex-based primers are likely the type of primer you’re most familiar with, as it’s typically the favorite for painting interior walls because. Latex-based primers are flexible and help smooth surfaces for a sleek finish.
Oil-based primers take a little longer to dry than latex or shellac primers, but they have the added benefit of compatibility with both oil and latex paints. They’re great for use on wood and metal surfaces like steel, and they also work well for covering stains.
Shellac primers dry more quickly than oil-based paints typically used to spot-block odors and stains from animals, smoke damage from fires, cigarette odor, and greasy food stains.
Roll-on or Paint-on Primer
This is more of a broad category than a specific type of primer, but it’s important to distinguish that many types of primer can be hand-painted, rolled, or used with a paint sprayer (which is different from typical spray paint).
Spray Paint Primer
Spray paint primer comes in a ready-to-use can like spray paint and is used to prime surfaces in most spray painting projects. Spray paint primer provides the same uniform, brush stroke free finish that spray paint does.
Benefits of Primer Paint
Neutralizes original paint colors.
One of the biggest benefits of using a primer before painting is that it will help neutralize any underlying colors so the new one can really shine.
Helps paint stick to porous or slick surfaces.
Primer makes it possible to paint slippery surfaces or porous surfaces like wood, allowing you to customize the color of almost any surface!
Helps paint last longer.
Because primer helps paint stick to a surface, using the right one can prevent chips and peeling in the long run.
Makes the finish look more professional.
Using primer can help create a smooth, even finish on your painting project and will help the colors show up as vibrant as they’re expected to!
Covers stains and imperfections.
Primer can help cover stains and greasy spots that would otherwise show through a coat or two of regular paint.
May reduce the amount of paint needed.
Using primer may prevent you from having to apply extra coats to get the desired look, and it will prevent paint from absorbing into the surface.
Protects and seals the surface that’s being painted.
Primer acts as a barrier between the surface and the paint being applied, as well as traffic, moisture, and other elements that may affect the surface over time.
How to Use Primer
The process for using primer may vary depending on the type of DIY project you’re using it for, but it will usually go something like this:
- Prep the surface you intend to paint
Make sure your surface is clean and dry before painting. Some surfaces may require a light sanding to help the primer stick, but it’s not necessary for every painting project.
- Apply the primer
Once your surface is ready to go, you can apply the primer using your chosen method, whether that’s using a paint brush, paint roller, paint sprayer, or using spray paint primer.
- Allow it to dry and reapply if necessary
Once the first coat has fully dried, you can apply a second coat to cover colors and stains or spot paint where it’s needed. In some cases, it may be necessary to lightly sand the primer between coats.
Is a Primer Always Necessary?
Primer isn’t mandatory for every project. It will greatly improve the quality of most paint jobs, but it isn’t strictly necessary in all cases. Whether you’re trying to save time, money, or energy, you might be able to skip the priming coat depending on a few factors.
When to Use Primer
When painting a lighter color over a darker one.
Primer is almost always necessary in the case of painting a lighter color over a darker one because it will neutralize the dark background and provide a blank canvas for your light color.
When covering stains or imperfections.
If you don’t use primer when covering stains, greasy spots, or other surface blemishes, you may find that the stain bleeds through the new paint color or the imperfections are still noticeable.
When painting on wood, veneer, plastic, metal, or other tricky surfaces.
Primer helps paint grip surfaces that it would typically have trouble sticking to or might peel away from. You should also always prime RAW wood.
When going from a glossy paint to a more matte finish.
A glossy finish is hard to cover if your new paint doesn’t have a similar finish. Primer can help cover the gloss to really mattify flat finishes.
When painting high-moisture areas.
Some primers act as a sealant to protect walls, furniture, and other surfaces in high-humidity areas like bathrooms, kitchens, basements, and outdoor surfaces.
When to Skip the Primer
When repainting using the exact same color.
If you’re just freshening up an existing color and there aren’t any noticeable permanent marks on the painting surface, you might be able to get away with skipping the primer.
When painting a darker color over a lighter one.
Darker colors can usually cover lighter colors without issues, but if you’re using colors from different families, it may affect the hue of the final paint color.
When using a 2-in-1 paint with primer.
Some paints contain primer in them, and in most cases that’s enough to skip the additional primer coat if you’re painting a project that isn’t raw wood. Raw wood, however, soaks up a lot of paint if not primed first so in those situations, start with the cheaper primer.
Tips for Using Primer
- Use the same application technique you’ll use for the regular paint coat for a cohesive finish.
If you plan on rolling your paint on, you should also roll your primer on instead of using a paintbrush to avoid streaky brushstrokes from showing.
- Allow it to dry fully before painting over it.
Exercise patience when priming a surface so you don’t accidentally end up mixing the paint with the primer or ruin the finish by painting too early.
- Don’t use expired primers.
Just like paint, primers don’t last forever! Most primers expire around 2-3 years after opening.
Use Primer for DIY Projects
Hopefully this answered all of your burning questions and you’re no longer asking, “what is primer?”. For painting projects and more DIY inspiration, check out the DIY section on DIYDanielle.com!
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