Remodeling Intel

Here’s What to Know About Primer

A primer on which type of primer to use and when.

Sponsored by

Primer is a multi-tasking product that elevates any painting project. Understanding the many differences in primer types is the first step in producing the highest quality results.

Primer vs Topcoat
Primer is basically white paint that contains a higher level of resin than regular paint. It seals and smooths surfaces while creating a base that paint can really “grab” onto. Because paint contains less resin, it doesn’t stick to surfaces the way primer can. Without primer, it’s necessary to use more coats of paint and the paint can end up cracking, peeling, bubbling and fading. Also, paint typically costs more than primer which means a more expensive project if more coats are used. Primer is designed to solve surface problems before you paint; which achieves better longer-lasting results and costs less.

Main Primer Types
There’s a wide variety of primers on the market, but in general, there are two main types.

Water-based primers, also known as Acrylic or latex primers, contain low volatile organic compounds (VOCs), dry quickly and are easy to clean up with water. They work great on most surfaces to be painted like drywall, wood and masonry and they are compatible with both latex and oil-based paints for their topcoats. High-performance latex primers also have excellent durability.

Pro Tip: It is not recommended to use a water-based primer (or paint for that matter) over oil-based paint. If you’re trying to paint over old oil-based paint, use an oil-based primer first; let it dry and then apply the water-based paint.

Oil-based or alkyd oil primers have high VOC content, are sometimes more durable than latex primers, have a longer drying time and require solvents like mineral spirits or paint thinner for clean-up. They are flexible, so they work well on exteriors that have weather fluctuations. Also, they typically work well for anything that rusts, like steel and wrought iron. If your topcoat will be oil-based, use oil-based primer to get the best adhesion.

Pro Tip: You can use an oil-based primer on top of water-based or water-based paint. However, it is not recommended to apply a water-based paint on top of oil-based paint or a water-based primer over oil-based paint.

PRIMER PAIRINGS
With so many primer choices out there, which should you choose? Here are some project and primer pairings to help get the job done right.

New Drywall

Polyvinyl Acetate (PVA) primer is formulated specifically for new drywall. It seals the paper and spackle on new drywall, producing a smooth surface that won’t soak up topcoats like a sponge.

Previously Painted Interiors

Stain-blocking primer covers stains caused by permanent markers, graffiti, nicotine, grease, smoke and more. Some primers can also effectively prevent unpainted wood tannin stains from bleeding through to a topcoat.
Odor-blocking primer creates a barrier that seals away odors caused by things like fire, nicotine, pets, and food. Because the molecules that carry those odors stick to just about everything, it’s best to cover every surface, including subfloors, drywall, woodwork, plaster and masonry, with an odor sealing primer like KILZ RESTORATION.
2 in 1 paint and primer products such as BEHR ULTRA SCUFF DEFENSE have latex primer mixed right into the tinted paint formula, so one coat is often all you need to cover a similar color. Also, this kind of product seals and smooths surfaces better than paint alone.

Unpainted Exteriors

Both latex and oil-based primers work well for preparing wood, stucco, or fiber cement exteriors for painting. If painting wood, choose a primer that can block tannin stains particularly for tannin-bleeding woods like oak, walnut, cherry and mahogany.

Cracked/Peeling Painted Exteriors

Peeling Paint Binding primer contains a formula that glues down cracking and peeling paint. It’s not a better solution than manually scraping and stripping paint and then priming and painting anew, but it’s especially helpful for problem areas that continue to crack and peel due to weather fluctuations.
Peeling Paint Binding primer contains a formula that glues down cracking and peeling paint. It’s not a better solution than manually scraping and stripping paint and then priming and painting anew, but it’s especially helpful for problem areas that continue to crack and peel due to weather fluctuations.

Masonry

Masonry primers are specially formulated for stucco, concrete and brick. This type of primer ensures the surface won’t soak up topcoat paint while still allowing the masonry to breathe. Some masonry or concrete primers are alkali-resistant or pH resistant up to a certain level which allows the primer to be applied to fresh concrete and masonry which would otherwise take as long as 30 days to cure before painting can occur.

Battling Natural Conditions

Mold and mildew-blocking primers are ideal for damp areas like bathrooms, basements, laundry rooms or exterior shaded areas. They contain ingredients that may kill mold and mildew and prevent it from growing on the primed surface.
Sun-blocking primers have UVA protection built right in, helping prevent the topcoat from fading in direct sunlight—a great value for darker hues on exterior surfaces.