All you Need to Know for a Perfect Primer Coat

Priming wood is among the essential practices during painting. But is primer waterproof? Let’s find out…

A primer soaks into the lumber pores and helps the topcoat bond with the surface delivering a better coverage.

Also, the formula enhances paint adhesion, guaranteeing a durable project. Thus, you will not deal with paint peeling and cracking issues later.

However, most woodworkers still wonder if priming the surface makes it waterproof. The primer soaks into the wood’s fibers, but does it seal them? This takes us back to our topic of discussion-Is Primer Waterproof?

The primer is not waterproof. It does not protect the surface from prolonged moisture exposure.

In addition, the formula has a limited duration when you can leave it exposed on the wood.

However, you can make a primer water-resistant to a certain extent. But still, it will not be waterproof.

Again, primers benefit the painting process, and sometimes it is impossible to overlook them.

So, read this write-up for more information on the product, handling it, and a few tips for a Perfect Primer Coat.

What Is Wood Primer?

Image of surface prepared with the best oil based primerWood primer is a preparatory undercoat on wood. It prepares the surface for staining or painting.

The product enhances better topcoat adhesion and protects the workpiece. Hence, you are sure of a more durable workpiece.

Further, you do not have to use a wood primer when working on previously finished surfaces.

However, applying the formula to new or bare wood is advisable for more uniform and complete topcoat coverage.

Moreover, new wood needs a stain-blocking primer, whereas older and more weathered lumber requires an oil-based or high-quality latex formula.

Wood primers come in three categories: Oil-based, water-based, and Shellac-based.

Oil-Based Wood Primer

Oil-based primers are an industry standard for most woodworkers.

Moreover, they work with latex and oil paints, making them versatile and applicable to multiple surfaces.

The product works well on wood, painted or unpainted, steel and other metals, and materials with an existing paint finish.

Although the primer is suitable for almost any workpiece, please avoid it for masonry and galvanized metal.

Besides, it is especially ideal for lumber. The formula easily seals the wood’s surface and allows smooth paint application.

Most oil-based primers are perfect stain concealers. They prevent wood stains and flaws from showing through the new paint coat.

In addition, the formula blocks various blemishes on surfaces ranging from nicotine, water, and ink.

Oil Based Primer work best for indoor and outdoor bare or unfinished wood. They seal the lumber’s surface, enabling the paint finish to deliver a uniform finish.

Further, the primer stops tannins from Cedar or Redwood from bleeding through the paint finish. It also slows down or prevents paint cracking, blistering, and peeling.

As a result, you deliver a durable project.

Oil-based primers have drawbacks to consider before choosing them. For instance, they dry slowly and release high amounts of VOCs.

Thus, prolonged product exposure causes health hazards.

The formula needs up to 24 hours before recoating. But they bond more potently to the surface than other primer types.

So, your patience will bear fruit and deliver a successful outcome.

In addition, we have new oil-based primer types that dry faster. Hence, do your research before purchasing the product.

Work in a well-ventilated workspace for enhanced safety. And open the windows and doors when working indoors.

Also, prolonged exposure to the product’s fumes leads to eye and throat infections, nose irritation, and even cancer.

Thus, wear a facemask to avoid inhaling the toxic fumes.

Oil-based primers require harsh solvents and thinners during clean-up. Otherwise, your brushes and applicators will pose an environmental threat after disposal.

Lastly, please adhere to the recommended disposal tips when disposing of the formula, rollers, brushes, and painting equipment.

Water-Based Wood Primer (Latex Primer)

Water or latex-based primers are perfect if eliminating or reducing toxic fumes is a priority.

Besides, nearly all water-based formulas offer either low or no VOCs. Therefore, you are sure of enhanced safety.

Choose this product when painting around children or anyone with breathing problems.

Latex-based primers are also ideal for prepping unfinished drywall, masonries like concrete blocks and brick, bare softwoods like Pine, and galvanized metal.

But it is advisable to clean these surfaces thoroughly to facilitate a professional outcome.

A water-based primer is perfect for unfinished drywall as it evens the workpiece and covers repaired or patched areas.

It is also more flexible and fast drying than an oil-based alternative.

In addition, you will have fewer peeling and cracking cases since the primer coat is less brittle than an oil-based formula.

The product can seal and cover minor stains from crayons, lipstick, and smoke. But it is not as effective as Shellac and oil-based options.

However, please avoid latex-based primers for Cedar wood.

The lumber needs an oil-based formula to prevent tannin stains from bleeding through the surface.

But still, a water-based primer is safer thanks to its low VOC content.

In addition, it is easy to handle and dries faster. Therefore, it accommodates multiple indoor projects.

Further, only use latex-based products when working with minor stains. 

However, other projects, such as painting over hardwood, old paint, or large, smelly, and dark stains need Shellac or oil-based primers.

Pair the primer with either acrylic or latex paint to deliver a successful outcome. Moreover, please do not use it for metal or hardwood.

Unlike oil-based formulas, water-based primers are easy to clean. They are water-soluble and easy to wash off with water and soap.

Finally, although the product is fast drying, it delivers a more durable paint surface. Thus, it comes in handy when you are working with a deadline.

Shellac-Based Wood Primer

Shellac wood primers have been around for centuries. They seal the wood and other materials, achieving excellent paint jobs.

This formula is perhaps the best stain-blocking primer on the market. It conceals severe smoke and water damage and related smells.

The wood primer is also perfect for preventing typical rust, water, and smoke stains.

You will not have to stress about wood tannins bleeding through your professional paint finish. The base coat also seals wood knots and pitch pockets.

Shellac primers are suitable for multiple materials, including plaster, plastic, metal, and wood.

This product is the best alternative for new or painted wood. Moreover, it is highly adhesive and fast drying.

You can also use it with latex-based and oil-based paints.

However, the primer does not dry as fast as water-based options. Thus, consider your project timelines before choosing it.

The drawback to using Shellac primers is that they are not versatile and produce more VOCs. In addition, you require denatured alcohol when thinning or cleaning applicators.

Thus, use the product in a well-ventilated area and always wear a protective air mask during operation.

Further, only apply it on interior projects and be prepared for more difficulties when cleaning brushes and painting materials.

What Is the Difference Between Wood Primer and Wood Coating?

A wood primer is a preparatory base coat added to lumber and other surfaces like plywood.

Further, it comes in handy before applying paint or varnish and guarantees a durable finish.

The formula serves various purposes when applied correctly. For instance, it protects the lumber from pests, harsh environmental factors, and household chemicals.

Wood primers block unwanted stains on the workpiece while improving paint or stain adhesion.

They also prevent quick topcoat absorption and promote a professional finish.

Consider a high-quality water or oil-based primer for new, old, or weathered wooden surfaces. 

In addition, prepare the surface thoroughly with sandpaper before applying the primer.

Further, wipe the surface with a wet cotton cloth and let it dry thoroughly before adding the topcoat.

Then, apply two finish coats and allow enough drying time.

On the other hand, a wood coating comes after the paint or stain coat. Moreover, you can call it the topcoat.

Apply the coating over wooden materials to protect them from sun, grease, dust, water, and household chemicals.

Topcoats are usually clear and often polyurethane-based. Besides, they give the surface a glossy or matte appearance.

The formula protects the finish and the wood underneath. And it works best after you clear the surface of grease and dirt particles.

Hence, wipe the paint or stain coat thoroughly before adding the topcoat.

You can apply the coating like primers with a spray machine or brush. Also, apply two or three layers for optimal results.

Finally, give the project enough drying time between coats for the best outcome.

Advantages of Wood Primer

Although it is a lot of work, there is no harm in applying a high-quality primer before painting.

A primer fills out wood blemishes and ensures the paint does not penetrate the surface unevenly.

In addition, it forms a protective film on the lumber, allowing for a smooth, level, easy-to-paint-on surface.

Other key benefits include:

  • A Primer Guarantees a Smooth Finish

You need a smooth, well-prepared surface to deliver a professional finish. Besides, the surface texture you paint on determines the final product’s design.

In most cases, bare wood needs more than two paint coats to balance imperfections. 

The rough, unprimed surface soaks up a great deal of paint. But it will still give a sub-par result. 

Thus, you’ll use more formula amounts and still risk an unsuccessful project.

Thankfully, a primer comes to your rescue as it levels the surface before painting.

Further, you’ll need a few paint coats to ensure complete coverage and maximum surface protection.

However, glossy surfaces pose a challenge to primer and paint application. 

The formula does not adhere properly to the wood, leading to a poor result. So, assess the workpiece and confirm that it is primer and paint friendly.

  • A Primer Eliminates Flaws and Covers Stains and Grains

One of the primer’s most essential qualities is its ability to conceal various wood blemishes.

Moreover, it is easy to deliver a professional finish with paint when you hide the lumber’s imperfections.

However, you cannot toss on some primer and paint on the workpiece and expect an expert finish.

Instead, the project needs considerable care, time, and patience. Otherwise, you will see marks, blotches, and stains if you make a mistake.

  • A Primer Helps Save Cash

A paint primer is cheaper than actual paint. So, it makes sense to use it before painting the surface.

Priming helps save a considerable paint amount while facilitating a longer-lasting finish. Thus, you save more over the years.

How Long Should Primer Dry Before Rain

The primer needs one hour to dry before the rain. Once the formula is dry, light rain will not penetrate it.

Further, the rule of thumb is that if the substrate is dry during primer application, rain should not ruin it in thirty to sixty minutes.

A primer should dry to the touch before heavy rain, or it will wash off.

Also, wait for the rain to stop if it rains before the primer dries. Then, scuff the surface, sand it, and primer it again.

Remember, oil-based primers need more time to dry, but they can handle light rain.

So, consider using them if you must prime and paint your workpiece during a rainy season.

Lastly, the rain slows down the drying process and, even worse, changes the wood’s appearance. 

But fortunately, it will not change the product’s bonding quality.

How Long Does Primer Take to Dry Outside?

A primer dries in 30 to 60 minutes. However, it has to cure before you add other coats.

In this case, wait at least three hours before applying subsequent primer coats or pulling out the new color.

Further, several factors affect the product’s drying time. Therefore, you may wait longer than one hour or sixty minutes before going to the next step.

These factors include:

Type of Primer

We have four primary primer types: Oil-based, Latex-based, Shellac-based, and Self Priming.

  • Oil-based Primers

The product is versatile and works perfectly on bare wood and porous surfaces. It seals them and delivers a better foundation for the topcoat.

In addition, an oil-based primer works well with latex and oil-based paints: thus, accommodating multiple projects.

You can use the primer for indoor and outdoor applications and expect a professional outcome.

However, remember that the product releases high VOC amounts. So, please work in a well-ventilated area for interior paint jobs.

Oil-based primers dry slowly, needing six to eight hours. The formula is also heavy, and you’ll have to sand brush strokes before adding the paint coats.

  • Latex Primers

These primers are water-based, meaning water is their primary solvent.

As a result, the formula is suitable for unfinished drywall. It evens out the surface and dries to the touch within one hour.

Latex primers also cover and conceal previous stains. But they are not as good as oil-based formulas.

  • Shellac Primers 

Shellac primers are your go-to option for covering stains from water or smoke damage. Moreover, they even curb foul odors.

The primer works flawlessly on multiple surfaces, including plaster, metal, plastic, and wood. You can also use it with latex-based and oil-based paints.

Further, it dries within 60 minutes, after which you can add subsequent coats.

  • Self-Priming Paint

This formula is a paint-and-primer designed to save you money and time.

Besides, it is a paint with priming attributes. Therefore, you do not need to purchase or apply two products.

Most self-priming paint dries to the touch in two hours, and you can add another coat in less than an hour.

Factors Affecting the Drying Time of Primer

Some of these factors include:

  • Temperature and Humidity

Most primer brands recommend room temperature as the ideal drying condition, say 40 to 80 degrees Fahrenheit and 85% humidity.

Hot or humid air prolongs the drying duration, whereas cold conditions make the primer too thick. 

As a result, the formula application becomes a bit challenging.

Further, latex paints freeze in cold environments. Therefore, it is advisable to wait for steady temperatures before applying the primer.

The humidity and temperature recommendations apply to interior and exterior applications. 

However, it is easier to manage conditions indoors. For instance, set your thermometer and try a dehumidifier if it is too humid.

On the other hand, you have less influence over environmental variables when priming outside.

So, watch the weather forecast and plan to work during optimal conditions.

  • Coating Thickness

Using thick primer coats also prolongs the drying duration. Further, apply enough primer, but not too much.

Also, various primer brands have different drying times. Thus, read and adhere to the manufacturer’s instructions.

  • Ventilation

Improve the room’s airflow when working indoors. This way, you decrease the drying time while delivering an intact finish.

In addition, please open doors and windows when handling Shellac and oil-based primers.

They have more potent chemicals than latex primers and produce harsh fumes during application.

  • Surface You’re Priming

The workpiece determines the drying time. For instance, metal needs a longer duration, up to four hours.

Moreover, priming stained wood, new drywall, or darker surfaces requires more than two coats.

As a result, depending on the workpiece, you’ll need more time.

Generally, it is a best practice to follow the manufacturer’s directives on drying time. But we have several methods to speed up the process.

They include:

  • Keep the Humidity Low. Use a dehumidifier to stabilize the humidity levels or wait for a less humid season.
  • Apply Light Coats. Thinner primer coats dry faster than thicker ones. Therefore, consider thin coats to speed up the drying duration between applications.
  • Use Fast-Drying Primers. Get a fast-drying product when working on a close deadline. For instance, self-priming paint is a perfect option, combining paint and primer in one formula.

However, you can use a latex primer if a separate primer is mandatory.

  • Use a Hairdryer. Blow the primed surface with a hairdryer. But please avoid high heat and keep the device at least one foot from the wood.
  • Increase Air Circulation. Open the room’s doors and windows to increase air circulation and enhance drying.

Does Primer Absorb Water?

Typical traditional primers are porous. Besides, their primary job is to bond to the workpiece, not waterproofing.

 Also, they only deliver a substrate for the topcoat to adhere to, facilitating a durable finish.

However, some modern primers, such as the self-etching ones, seem to make the surface water repellent.

In addition, epoxy primers are confirmed to be waterproof. They have more texture and are not porous. Thus, they do not absorb water.

How to Apply Primer to Wood

Painting lumber appears to be elemental and foolproof. 

And as such, many woodworkers rush the job and attempt shortcuts, producing poor results.

Moreover, primed trim and casing and drywall surfaces are not forgiving. The paint job slowly becomes a lost art.

Fortunately, the process is pretty straightforward. It only needs you to be keen and use the recommended materials.

For example, wear a dust mask to avoid breathing or ingesting wood and paint dust when sanding. Also, wear hearing protection when handling an oscillating sander.

Below are simple tips to transform you into a professional woodworker.

  • Step 1: Get the Correct Equipment

You’ll need:

  • Plastic sheeting
  • Rubber gloves
  • A canvas drop cloth
  • Eye and hearing protection
  • Clean cloths
  • A bucket
  • Random orbital sander
  • Two ½-inch paintbrushes
  • A paint tray and liner
  • Primer
  • Trisodium phosphate
  • Roller assembly with a high-density foam cover
  • Tack cloth
  • Interior acrylic-latex paint
  • 180 and 220-grit sandpaper
  • Paint additives like Floetrol or Penetrol


  • Step Two: Cover Your Work Area

Drape the plastic sheeting over the work surface to protect it from accidental paint spills. Also, lay a contractor’s paper or canvas drop cloth over the plastic sheeting.

The sheeting keeps the formula from soaking to the floor, and the canvas provides a non-slip working area.

So, you contain paint spills and slips and minimize the cleaning hassle.

  • Step Three: Clean the Wood

Wear eye protection and rubber gloves. Then, mix a TSP and warm water solution following the manufacturer’s recommended proportions.

Dip a cloth in the mixture, squeeze it dry, and wipe the surface. This way, you remove all dirt, oils, and grime.

Next, rinse the wood with clean and warm water and wipe it with a clean rag.

Let the surface dry thoroughly.

Evaluate the workpiece for large gouges, nicks, and scratches when the wood dries. Then, fill the blemishes with a wood filler.

Further, TSP is a strong degreaser, cleaner, and deglosser used for cleaning surfaces. It is a perfect substitute for phosphate cleaners.

  • Step Four: Sand the Surface

Wear hearing protection and a dust mask or respirator, depending on the available gear. Then, sand the wood with 180-grit sandpaper and a random orbital sander.

The intention is to smooth the surface and deliver slight scratches to enhance the paint bond.

Therefore, you do not have to strip the lumber of all stains and coatings.

Further, switch to sand-handing when working on uneven surfaces. This way, you deliver better coverage.

  • Step Five: Clean Off the Dust

Remove the sanding dust from the wood. You can start with a shop vacuum fitted with a brush attachment.

Also, ensure the accessory has a bag and filter to minimize airborne dust.

Please avoid blowers as they only redistribute the dust to the surface, resulting in a more tedious clean-up.

The next step is to use a cotton rag or cloth dipped in water to remove the remaining dust.

  • Step Six: Prime the Lumber

Stir the primer well and apply it with a roller, brush, or sprayer.

However, read the manufacturer’s directives carefully to determine the best applicant for your product.

Also, add another primer coat if the first layer looks streaky or transparent.

Finally, use a roller to speed up the application process when working on extensive surfaces. It also guarantees a smoother finish.

  • Step Seven: Sand the Primer

Allow the primer to dry thoroughly and sand it before painting.

Moreover, use 220-grit paper and apply light pressure. Otherwise, you may gouge the primer finish.

Lastly, remove the primer dust using a quick brush from the vacuum. Then, lightly wipe the wood with a tack cloth.

Here’s a Video On How to Apply Primer to Wood:

What Happens If You Paint Wood Without Primer

Priming wood seems like an unnecessary exercise, especially if you want to apply multiple latex coats.

However, omitting the formula is a mistake that compromises the final result.

In addition, you are likely to deliver an unsuccessful project despite having multiple latex coats.

Moreover, failure to prime the workpiece causes uneven coverage. The finish coat will also be more vulnerable to chalking, peeling, and other defects.

Remember, the primer does not just deliver an opaque base coat. It also fills the grain wood due to its high solids content.

Besides, it has a more adhesive binding agent, causing it to stick better to lumber than paint finishes.

A primer will prevent wood tannins from bleeding through and block stains, especially when painting knotty wood like Pine.

If you do not prime Pine, it will absorb paint unevenly, leading to a botched surface.

In addition, the water in the paint raises the grain around the knots. And you’ll get a bumpy finish.

The second paint coat can correct these flaws but not having a primer makes it challenging. Worse still, the finish will peel in a year or two.

Omitting a primer for pine wood makes dark spots around knots visible.

Unfortunately, you cannot eliminate these marks despite having multiple paint coats. So, take some time and primer the lumber to avoid unnecessary nuances.

We have some exceptions where you can paint without a primer:

  • Multi-Purpose Primers

These products are famous for their universal applications.

However, please be careful as manufacturers may oversell the formula even in inappropriate situations.

Also, ensure the multi-purpose primer states its appropriateness for your intended application.

  • Paint & Primer In One 

This formula is among the newest and most popular trends in woodworking. It primes while it paints, saving you money, energy, and time.

But the product has limited applications. Therefore, stick to the highest-quality brands and only use them for recommended projects.

Frequently Asked Questions

Some of the most asked questions include:

  • What Happens If I Paint Over Primer Too Soon?

Primer is an undercoat acting as a paint foundation. Further, it enhances the paint’s adherence, increasing the project’s durability.

However, applying the paint too soon before the primer dries can ruin your project.

For example, the primer can pull up from the surface during painting, delivering a streaky mess. As a result, you deliver an uneven, flaky, and peeling finish.

In addition, applying paint too soon before the primer dries prevent the latter from sticking correctly. So, the project fails sooner or later.

Always wait until the primer dries fully before adding the paint coat. Moreover, wait longer than the recommended time to deliver a successful project.

After the surface dries, test an inconspicuous spot. Touch the formula with your finger and wait for thirty minutes if you feel it’s dry.

Finally, apply the paint to an invisible area to check whether it peels, rolls up, flakes, or changes color.

  • Can I Use Water-Based Primer on Wood?

You can use water-based primers on lumber. They are also excellent for drywall, unfinished wood surfaces, bricks, softwood, and galvanized metal.

Water-based primers are quick-drying and easy to handle with a brush or a roller. Also, they have fewer VOCs and a low odor: thus, are perfect for indoor applications.

However, please avoid this primer when handling Cedar.

Cedar wood requires an oil-based formula to keep tannin stains from bleeding through the surface.

In addition, a water-based primer raises Pine’s wood fibers, resulting in a bumpy surface.

  • How Many Coats of Primer Do You Need?

Various textured materials need a different number of primer layers. 

For example, bare walls require two primer coats as the first seeps into the porous surface.

Further, you need two to three layers if the wall has a brighter color.

An extra layer guarantees a better finish. It covers the previous shade without exposing hints of the old, bright-colored surface.

On the other hand, one primer layer is enough for white surfaces or walls with pre-existing light-colored paint.

Lastly, professionals advise woodworkers to repair and clean the surface before priming and painting.

  • Does Primer Cover Wall Imperfections?

A primer covers wall blemishes, but only to a limited degree. Therefore, prepare the surface thoroughly before applying the formula.

Besides, the primer’s primary function is to cover repairs, not to act as the repair.

You cannot fix cracks and holes with one or two primer coats. Instead, patch them with a spackling compound.

Standard compounds need one to two hours to dry, although experts recommend a 24-hour wait before sanding.

  • Is Paint-and-Primer In One Good?

Manufacturers design this product with the promise of enhancing a woodworker’s convenience. 

You will not have to buy a primer and paint for your work.

Thus, a paint-and-primer-in-one formula is an excellent option if you want a shorter project duration.

Moreover, it works perfectly on priorly primed surfaces like an old painted wall and delivers perfect coverage.

But again, a paint-and-primer does not hold well on unprimed materials. Thus, consider a primer for bare wood and porous surfaces. 

It supports the paint and acts as a suitable base for colors, facilitating a brighter and more solid finish.

  • How Many Paint Coats Do I Need After Primer?

Generally, a single paint coat is not enough to deliver adequate coverage and rich color.

Further, various paint types have different recommendations on the paint layers needed.

For instance, new walls or previously painted surfaces require two paint coats. But you only need one paint coat when painting the wall with the same color.

A newly installed drywall section, wood, or siding has a relatively porous surface. Thus, the first coat will soak into the wood and may not deliver the required color.

In addition, use two layers when painting over dark surfaces with a light hue and vice versa.

Dark colors are exceptionally challenging to conceal. So, choose a high-quality primer to avoid having more paint coats.

Further, exterior surfaces require at least two paint coats for maximum durability and protection.

On the other hand, you can get perfect coverage with one paint coat when repairing and repainting a surface.

But the color should be the same as the previous one. Otherwise, you will need more coats to alter the shade appropriately.

Lastly, work carefully and patiently when priming and painting. Give the paint coats 24 hours to dry before adding the next.

This way, the finish holds up excellently and looks lovely for a longer duration.


Primers are popular in woodworking and automotive projects. They prepare the surface to receive the paint, guaranteeing a lovely, durable finish.

In addition, the product is available in multiple versions to accommodate different applications.

For instance, an oil-based primer works best for outdoor projects susceptible to the elements.

But most users have concerns about a primer’s water-resistant qualities. So, check out the discussion above on:

Is Primer Waterproof?

Unfortunately, a primer is not waterproof.

Besides, the manufacturer does not design it for waterproofing the surface. Instead, it soaks into the material to deliver a uniform surface for the paint finish.

Primers also tighten the bond between the workpiece and the paint. As a result, you will not worry about the surface flaking, cracking, or peeling sooner or later.

Image of a woodworker wearing hearing protectors for woodworking

Tyron Otieno

Tyron is an avid woodworker and writer. He founded this website to help other woodworkers, whether hobbyists or professionals by sharing his knowledge and experiencie after a decade of woodworking.

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