Paint primer is an essential first step when painting any surface. Priming creates a uniform surface for paint to adhere to, enhancing its durability and appearance. This comprehensive guide will explain the basics of priming and primer, types of primers, and how to use them for common painting projects.

What is Paint Primer?

Paint primer, often simply called primer, is a preparatory coating applied to surfaces before painting. Priming uniforms absorbency, provides a bonding layer for paint, and allows topcoat adhesion. Primers seal porous surfaces like drywall and wood while providing extra corrosion resistance on metal. Most paints adhere best when applied over primer designed for that specific surface.

Primer preps surfaces for enhanced paint durability and aesthetics. Its advantages include:

Uniform Surface Absorption: Primer creates an even base absorption rate so topcoat paint looks uniform without variations in sheen.
Better Paint Adhesion: Primers chemically bond to surfaces and provide a textured layer for paint to grip, preventing peeling and chipping.
Stain-Blocking: Certain primer formulas block stains from bleeding through water-based topcoats. This includes markers, smoke damage, and water stains.
Corrosion Protection: Priming bare metal provides a protective coating to reduce corrosion and rust before applying paint.
Hiding Flaws: Primers help conceal surface defects like small cracks, grain irregularities, minor damages and color variations.

Why Should You Primer Before Painting?

Priming before painting is highly recommended for both interior and exterior projects. Primer provides essential benefits compared to painting directly on bare surfaces:

Longer-Lasting Paint Job: Priming enhances paint adhesion and durability, preventing premature chipping, cracking, and peeling. It provides extra longevity.
Better Coverage: Primer creates a uniform surface and often has higher hiding power than paint. This allows topcoats to fully cover in fewer coats.
Superior Color: Primer improves color accuracy and vibrancy of topcoat paint, especially on porous surfaces where unprimed paint can turn out uneven and muted.
Versatility: Select primers allow painting on slick surfaces like metal or glossy finishes where paint struggles to bond without a primer layer.
Stain-Sealing: Priming shields water-based paints from stains bleeding through from wood, smoke damage, markers and more.

Proper prep work like priming helps paint last longer with greater aesthetic appeal. While priming adds an extra step, it saves time and hassle compared to dealing with peeling or chipping paint later.

Types of Primers

Choosing the right primer helps ensure optimal paint adhesion and durability on each surface. Major primer types include:

Latex or Water-Based Primer

Ideal for interior walls and ceilings made of drywall, plaster, wood, masonry, unglazed brick, and porous concrete.
Bonds well to multiple surfaces and dries faster than oil-based. Low odor and easy cleanup with water.
Effective at sealing water-soluble stains. Latex primers include PVA, acrylic and styrene acrylic.

Oil-Based Primer

Provides excellent adhesion on surfaces glossy finishes, PVC, metals, exterior wood, laminate, tile and non-porous interior walls.
Seals persistent stains like grease, tannins, smoke damage, graffiti or markers bleeding through water-based paints.
Longer dry time but very durable bonding power. Harder to apply and requires mineral spirits for cleanup.

Stain-Blocking Primer

Contains barrier resins to prevent bleed-through from water, smoke, markers, grease and more.
Works on interior walls and ceilings, exterior siding, brick, concrete, wood etc. Ideal for covering nicotine stains.
Water-based formulas are lower odor than traditional oil-based stain blockers but slower-drying.

Bonding Primer

Sticks tenaciously to the slickest surfaces including glass, glazed tile, metals, laminate, vinyl, PVC and glossy paints or varnishes.
Allows painting materials that typically require sanding or deglossing before painting.
Extra surface-gripping additives provide top-tier adhesion power. Useful on damaged concrete or chalky exterior finishes.

Masonry Primer

Special alkali-resistant formulas designed for concrete, stucco, plaster, brick, cinderblock and other masonry.
Penetrates porous mineral surfaces to bind and harden weak material, reduce suction and prevent alkali leaching.
Important for exterior masonry painting. Latex or oil-based options available.

Aerosol Spray Primer

Primer in a spray can for fast, convenient application on irregular shapes, small repairs, metals, car parts etc.
Handy for priming difficult to reach spots. Does not provide the thickness of brushed primer.
Useful for spot priming repaired drywall patches between coats of paint.

When Should You Use Primer?

Primer is always recommended before painting bare drywall, wood, metal and masonry. It’s also extremely useful in these situations:

Painting Over Dark Colors

Dark paint colors, especially deeper reds, blues, greens and browns, often require a tinted primer or extra coats of paint to cover fully. Primer increases hide and uniformity.

Painting Over Glossy Surfaces

Slick, non-porous and glossy surfaces like tile, laminate, metals and varnishes have poor paint adhesion without proper priming first.

Covering Stains

Primers formulated to block stains allow painting over smoke damage, watermarks, grease, permanent marker, graffiti and more without bleed-through.

Painting Damaged Drywall

Fresh drywall repairs should be primed to create an even finish. Primer also fills cracks and improves paint coverage.

Painting New Drywall

Bare drywall must be primed before painting as drywall primer seals the porous gypsum core and keeps paint from soaking in unevenly.

Painting Over Chalky Surfaces

Weathered exterior paint or loose, chalky surfaces need the durability of primer before repainting to prevent the finish from washing off.

Painting Tile, Laminate or Vinyl

Primer bonds paint to difficult glossy or non-porous surfaces like ceramic tile, laminate countertops, cabinets, vinyl siding etc.

Painting Unpainted Wood

Bare interior or exterior wood needs an oil or stain-blocking primer to prevent tannin bleed-through and wood knots from showing through paint.

Painting Concrete and Masonry

Specialized alkali-resistant primers allow successful painting on exterior concrete, stucco, plaster, cinderblock and brick surfaces.

How to Choose the Right Primer

With different primers designed for specific surfaces, it’s important to choose the right one. Use this primer selection guide:

Drywall

For new drywall, use a high-quality PVA or drywall primer-sealer to prepare for painting. On previously painted drywall, an all-purpose latex primer works well.

Wood

Use an oil or stain-blocking primer when painting bare or stained wood to prevent bleed-through. For already painted wood, an all-purpose latex primer provides sufficient adhesion.

Concrete and Masonry

Specialty alkali-resistant primers made for concrete, plaster, stucco, cinderblock and other masonry work best for maximum paint adhesion and durability.

Metal

Antirust primers designed for metals provide corrosion resistance and excellent bonding power on ferrous and non-ferrous metals. Rust-inhibiting primers are best for rusted metals.

Tile and Laminates

For surfaces like ceramic tile, laminate cabinets, countertops and furniture that paint struggles to bond to, use a high-adhesion bonding primer.

Vinyl Siding

Use an exterior acrylic latex primer formulated for vinyl and plastic to re-paint exterior vinyl siding and trim for long-lasting results.

How to Apply Primer

To properly prime surfaces prior to painting:

Clean surface thoroughly and allow to fully dry before priming. Remove any grease, dirt or grime.
Fill any cracks, holes or damages with appropriate spackle or patch compound and sand smooth.
Lightly sand glossy finishes to roughen surface so primer can bind well.
Use painter’s tape and drop cloths to mask off any areas you don’t want primed.
Shake or stir primer thoroughly before and during use for uniform consistency.
Apply primer in even coats using a high-quality brush, paint roller or airless sprayer. Work from top to bottom.
Allow each coat to fully dry before adding another. Recoat if absorption remains uneven after drying.
Very porous surfaces may require multiple coats of primer to avoid topcoat soak-in.
Once primed, the surface is ready for painting with the appropriate topcoat paint.

Priming Tips and Tricks

Follow these pro tips for flawless priming results:

When priming fresh drywall repairs, extend primer onto surrounding areas to equalize absorption.
Only prime as much surface as you can paint topcoat on the same day to prevent primer drying out.
Tint primer close to your topcoat paint color for enhanced coverage, especially when painting over dark or vivid colors.
Apply multiple thin primer coats on highly porous surfaces rather than one thick coat which risks running or dripping.
Use an additive like sanding dust or granules to create extra surface texture when priming slick finishes for the topcoat to cling to.
Allow 2-3 days curing time for fresh concrete or masonry before priming for proper adhesion and durability.

Common Priming Questions

Confused about when and how to properly use primer? Here are answers to some frequently asked questions:

Do you have to prime before painting?

Primer is highly recommended before painting any surface, especially new drywall, woods, metals, masonry and to prevent bleed-through on stained surfaces. Primer enhances paint adhesion and durability.

Can you put paint over primer?

Primer is designed to be coated with paint. Once fully cured, primer provides an optimal base layer for paint adhesion. Match your topcoat paint to the specific primer used.

Do you have to primer before using paint with primer in it?

“Paint and primer in one” still performs best when applied over a layer of actual primer designed for that surface. The “primer” in such paints is not the same as a true primer.

How long do you have to wait to paint after priming?

Oil-based primer typically requires 24 hours drying time before painting. Water-based latex or acrylic primers only need 2-4 hours before they can be painted over once fully dried.

Should you sand between primer and paint?

Sanding between coats of primer is rarely needed. However, you can lightly sand primed surfaces before painting to remove any nibs or roughness for an ultra-smooth topcoat finish.

Can you put latex paint over oil based primer?

Latex paint can be applied over cured oil-based primer. Ensure the primer has dried fully, at least 24-48 hours. Scuff sanding helps latex adhesion over an oil primer.

Priming Different Surfaces

Proper surface prep with the right primer ensures your paint job has maximum durability and aesthetic appeal. Follow these priming tips for great results on key surfaces:

Priming Bare Wood

Sand surface smooth and wipe away dust. Fill holes and dents with wood filler and sand again.
Prime with oil-based primer or exterior wood primer to prevent tannin bleed. Allow overnight drying before painting.
For interior wood, you can also use a quality high-binder water-based primer designed for wood.
Lightly sand primed wood before painting for a smooth finish.

Priming Drywall and Plaster

Fresh drywall should be primed with a drywall primer-sealer before painting.
On previously painted drywall, an all-purpose interior latex primer is fine.
Fill dents, cracks and damages then smooth sanded before priming.
Extend primer onto surrounding surfaces when priming repairs to prevent flashing. Allow 2-4 hours dry time.

Priming Concrete and Masonry

New concrete requires full 28 day curing before priming.
Clean surface thoroughly and check moisture level before priming. Should be 15% or lower.
Use alkali-resistant masonry primer to block efflorescence stains and enhance paint adhesion.
May require multiple coats on porous or uneven surfaces. Allow 24 hours drying.

Priming Metal

Remove all rust, loose paint, oils and grime to bare metal by sanding, wire brushing, pressure washing or solvent wiping.
Priming bare metal immediately after cleaning prevents flash rusting.
Use rust-inhibiting metal primer for best corrosion resistance and paint adhesion. Allow overnight drying.

Primers to Use For Specific Paints

Match your primer to the specific paint you’ll be using for optimal compatibility:

Latex/Acrylic Paint – All-purpose latex primer
Enamel Paint – Latex or oil-based primer
Epoxy Paint – Shellac-based primer
Alkyd/Oil-Based Paint – Oil-based primer
Milk Paint – Oil-based primer
Chalk Paint – No primer needed but can use latex primer
Metallic Paint – Acrylic primer
Textured Paint – Latex drywall primer

Top Primer Brands

These top-rated primer brands deliver outstanding performance across different surfaces:

Zinsser – Trusted for stain-blocking and specialty primers like Cover Stain and BIN Shellac-base.
BEHR – Budget-friendly primers including MARQUEE Interior/Exterior Multi-Surface and Premium Plus All-In-One.
KILZ – Excellent for interior and exterior painting including Original Oil-Base and Adhesion Interior bonding primers.
Rust-Oleum – Leading metal and rust-inhibiting primers like Rusty Metal Primer and Automotive Primer.
Valspar – Quality options for multiple surfaces like Premium Sealing Interior/Exterior Latex Primer.
Sherwin-Williams – Pro-favored primers featuring PrepRite ProBlock Interior/Exterior and Multi-Purpose Latex.

When is Primer Not Necessary?

While priming is almost always recommended before painting, there are some exceptions:

Painting a similar color over itself or over well-adhered existing paint.
Using paint specifically formulated for certain surfaces like galvanized metal or vinyl.
Paint with built-in primer may be sufficient for small touch-ups or dark colors.
Chalk paints and milk paints often don’t require primer on raw wood and furniture.
Short-term or temporary paint projects where longevity is not a priority.

Conclusion

Primer is a vital preparatory step that leads to better paint adhesion and aesthetics on nearly any surface. Matching the primer to the specific surface ensures optimal bonding, stain blocking, and uniform appearance. Oil and latex primers both provide excellent options. Be sure to allow proper drying time before painting over primer. Investing in a quality primer pays off with longer-lasting, better-looking paint results that are well worth the extra effort. With the right prep work, your painted surfaces will stay looking freshly painted for years to come.

FAQ About Paint Primer

Primer is an essential part of painting, but many people have questions about proper use. Here are answers to some frequently asked questions about paint primer:

Why do you need to use primer?

Primer provides important benefits for the paint job including better adhesion, more uniform finish, improved stain blocking, and longer durability. Primer enhances the performance of paint.

What surfaces need primer?

Primer should be used on nearly all surfaces before painting, especially porous or absorbent materials like wood, drywall, concrete, plaster, and masonry. Primer helps paint last longer on exterior surfaces exposed to weather.

How does primer work?

Primer seals surfaces with a preparatory coating that helps paint bond better. It evens out different surface absorbencies so the topcoat looks uniform. Many primers also contain additives to block stains, prevent corrosion or improve adhesion.

Should you use oil or latex primer?

Oil-based primers provide excellent adhesion on glossy surfaces and blocking stains. Latex primers are better for interior porous surfaces, easier cleanup and low-odor application. Match the primer to the surface and paint finish.

Does new drywall need primer?

Yes, new drywall absolutely requires priming before painting. Unprimed paint soaks unevenly into drywall paper and joint compound differently, creating obvious visual variations.

Can you use paint without primer?

While paint and primer-in-one products are available, standalone primer still provides superior results. Primer bonds better to surfaces and prevents many paint problems that can occur without priming.

Do dark colors need primer?

Primer, especially tinted primer, is highly recommended when painting over darker colors with lighter paints. The primer evens out absorption for improved coverage.

How long should primer dry before painting?

Oil-based primers require 24 hours drying before painting. Latex or acrylic primers only need 2-4 hours drying time before they can be painted over.

Does primer expire or go bad?

Both latex and oil-based primers have a shelf life of around 2-3 years if stored sealed in ideal conditions. Primers may skin over or become too thick if left open for extended periods.

How do you apply primer?

Primer can be brushed, rolled, or spray applied much like paint

Paint Primer: Guide to Basic Uses