If you have old wooden fixtures in your yard that are worse for wear, you may be thinking about replacing them. In some cases, this is the right choice because, once wood rot sets in and destroys the bulk of the wood, you can’t rescue it. However, in a lot of cases, a fresh coat of paint with the right primer, is enough to bring it back.
Primers will protect and seal the wood while also preparing them to take paint. The end result will revitalize old wood and protect it for years to come, but only if you use a good quality product. Read on to learn more about choosing the best exterior primers for wood.
What to Consider When Buying an Exterior Primer?
When buying an exterior primer, there are a few key considerations that will help you find the perfect product.
Can it Handle the Outdoor Elements?
This is the most important thing to look at when choosing an exterior primer. If it is going to be used outdoors, it will be exposed to rain, sunlight, and temperature fluctuations. A low-quality primer won’t be able to handle the outdoor elements and it will crack and peel, taking the top layer of paint with it.
Pay particular attention to the moisture resistance and how it handles temperature changes. If it contracts and expands a lot as the temperature shifts, it will crack. But good quality primers will be a bit more flexible, so they will be able to handle temperature changes.
Durability
The durability of the primer determines how long it will last before it needs to be reapplied. Weather-resistance is a big part of this, but you also need to consider the general durability of the primer.
Some high-quality products will last decades, while others will last less than 5 years before they need to be reapplied. Naturally, the more durable primers are more expensive, but it’s worth paying for because it saves you time and money in the future.
How Well Does it Adhere to the Surface?
Old wood is a difficult surface to adhere to. It has a lot of imperfections and it is quite porous, so it soaks up a lot of primer. The purpose of priming is to create an excellent base for the paint to bond to. So, if the primer doesn’t adhere well, the whole paint job will be sub-par and it will peel quickly. Finding a primer that adheres well to old wood is crucial if you want the job to last.
Does it Prevent and/or Slow Down Wood Rot?
Rot is a big problem for exterior wood, but some primers are designed to tackle it. They contain additives to prevent and slow down wood rot, preserving the surface as well as preparing it for paint. You should always look for products that help you deal with wood rot if you are working on an exterior project.
10 Best Exterior Primers for Old Wood
There are a lot of great primers out there that can help you protect old wood and create a good base for painting. These are some of my top picks.
1. Zinsser B-I-N Shellac Base Primer (Best Overall) 
Shellac is one of the best primers for old wood because it creates a very strong bond that blocks out stains and stops wood tannins from bleeding through paint. Old wood that has a lot of knots in it needs a strong primer to stop the tannins from leaking out and damaging the top layer of paint. That’s why Zinsser B-I-N Shellac Base Primer is the best primer for old wood.
This is such an excellent primer that bonds well to almost any material. It does require a few coats if you are working with dark wood, but it can cover anything you want. It dries into a solid white layer that is a bit tougher to sand than normal primer.
It has a very thin consistency, which is ideal for old wood. It gets into all of the small cracks and gaps in the wood and seals them, so there is no way that stains and tannins can leak through once the paint is applied over the top.
Zinsser primer can be a bit messy to use as it is thin and it splatters a lot. However, if you take your time and get a nice even covering, you will have the perfect base for painting.
2. Rust-Oleum Painter’s Touch 2X Ultra Cover (Best for Small Projects)
If you are working on small, intricate projects, Rust-Oleum Painter’s Touch 2X Ultra Cover is great. This oil-based primer comes in a spray can, so it’s super simple to apply, just spray on a coat and let it dry. It only takes 20 minutes to dry, so you can do a few coats in a day easily.
The nozzle works at any angle too, so it’s ideal for getting into tricky areas on small projects. If you are working on a large project, you may want something more robust that you can apply with a roller, but for small projects, a spray can is perfect.
You’ll get good coverage and it’s a very durable primer. Just make sure that you pay careful attention to areas with a lot of cracks and chips in the wood. The spray can isn’t as good as a brush or roller for filling those imperfections and sealing the wood, so you will need a few coats. The finish can easily be sanded to create a good base for painting.
3. INSL-X Block Out Acrylic Exterior Wood Stain Blocking Primer
The INSL-X Block Out Acrylic Exterior Wood Stain Blocking Primer is another great choice if you are concerned about the tannins from the wood leaking through into the top layer of paint. This is not a shellac product, it is a latex primer, but it’s still incredibly effective for sealing old wood before painting.
It has a very thick consistency, so you get great coverage and it hides a lot of imperfections in old wood. The thickness also makes it a bit easier to handle than other primers, like the Zinsser Shellac Primer.
If the wood is in relatively good condition, you can get away with a single coat. However, if you’re working with old wood, it’s best to give it 2 or 3 to be sure.
4. KILZ Adhesion Primer
Adhesion primers are designed to bond well to difficult surfaces like old wood, creating a good layer for painting. Low-quality primers will not give you the same strength of bond and it will peel quite easily. The KILZ Adhesion Primer is a tough latex primer that sticks well to surfaces that oil-based primers struggle with.
Although oil-based primers do work on wood, latex primers are a better choice for old wood that needs a very durable primer.
This primer goes on easily and it dries in just 30 minutes. It should be ready to recoat in an hour, so you can do 2 or 3 coats in a single day no problem. Once dried, it can be painted with either latex or oil-based paints, so it’s suitable for any woodworking projects.
If you test the durability of this primer, you won’t be disappointed. After it has had 24 hours to fully cure, you can scratch it with a nail and it won’t come off.
5. Zinsser Perma-White Exterior Satin
Zinsser Perma-White Exterior Stain is a high-quality primer that is designed for use on exterior projects, including old wood. When you’re sealing and painting wood outdoors, you need good protection from mildew and rot. This primer is one of the best for preventing rot for a long time, and you’ll get a great seal against the elements so your paint job goes the distance.
This product works best when painted over, but it can also be tinted, so it can be used as a 2-in-1 paint and primer. However, most of the colors are pastel shades and if you want a darker color, it’s best to paint over the top. If you leave it as it is, you get an excellent bright white finish, so if you just want a plain coverage, this is great.
Zinsser Perma-White is designed for use on a range of materials and many people use it for their bathrooms because it’s so durable, even when exposed to a lot of moisture. If you are painting old wood that is already damaged and is prone to rotting and moisture, this is ideal.
6. Behr Premium Plus Ultra Exterior Paint & Primer in One
Behr Premium Plus Ultra Exterior Paint and Primer in One is a great time saver because you don’t need to use two separate products. As the name suggests, it primes and seals the wood as well as acting as paint at the same time. The enamel paint has a nice satin finish and it’s incredibly durable.
The paint and primer is very thick and has an incredibly dense pigment, so you get a rich color and excellent coverage from a single coat. The thickness is perfect for old wood too because it fills up all of the pores and cracks and makes it look brand new.
Don’t be put off by the cost of this product. Even though it is more expensive, you save a bit of time and money because it’s a 2-in-1, and the finish will last for years to come.
7. Zinsser Cover Stain Interior/Exterior Oil Primer Sealer
Zinsser Cover Stain is another all-purpose primer that is formulated to block old stains on wood. It works brilliantly on tough stains like nicotine, water, and smoke, as well as wood tannins, so it’s ideal for bringing old wood back to life. The primer is suitable for both interior and exterior projects, and will stand up to the elements well.
It sticks to pretty much any surface, even silicone, so it has no problem bonding to wooden surfaces. You can use both latex and oil paints over the top and the finish will be excellent. It’s not as fast drying as other options but it will still be ready for painting in around 48 hours.
Be aware that it does have quite a strong odor. This will dissipate fairly quickly, but it’s important to have good ventilation if you are using it inside.
8. Zinsser Bulls Eye 1-2-3 All Surface Primer
Zinsser Bulls Eye 1-2-3 All Surface Primer is a simple to use, water-based primer that hides a lot of imperfections with a single coat (although you should apply at least 2). It also dries to the touch in 35 minutes, ready for recoating in an hour. People are tempted to skip the primer because they don’t want to do the extra work, but you don’t have to worry about that with Bulls Eye.
It’s excellent at blocking stains and it can be applied straight over the top of any old paint without sanding, just scrape off any loose paint and go straight on with the primer. It also takes all kinds of paint on top.
The finish is very flexible, which is ideal for exterior applications. When paints and primers are subjected to rapid temperature changes, they can crack and peel, but more flexible primers don’t have this problem, so they’ll last a lot longer. It is also resistant to mold and mildew, making it excellent for bringing exterior wood back to life.
This is a water based primer so when it goes on to raw wood, it can raise the grain a little bit and make the finish slightly rough. If this is a problem for you, just give it a light sand between coats and once it has fully cured.
9. Krylon COLORmaxx Primer Spray Paint
Spray paint is a great simple option for painting wood. If you want a quick job with minimal hassle, spraying directly onto new wood is fine. However, if you are painting old wood that has seen better days, priming it first is advisable. Krylon COLORmaxx Primer is specifically designed for preparing surfaces to take spray paint. It can be used on all kinds of materials including metal, plastic, and wood.
The spray can is so simple to use at all angles, and it’s touch dry in 10 minutes. It does go on quite thin and it drips relatively easily if you spray too close or you concentrate on one area for too long. Make sure that you keep the can a good distance from the surface and use broad strokes to avoid drips. It’s best to apply this primer outdoors because it can get quite messy.
10. INSL-X Stix Acrylic Waterborne Bonding Primer
INSL-X Stix Acrylic Waterborne Bonding Primer is one of the toughest primers on the market, designed to stick well to difficult surfaces, including old wood. The acrylic urethane formula is ideal for old wood because it fills gaps and cements everything together, so flaky wood will have more structure and the paint goes over the primer nicely.
It’s a water-based product too, so it’s easy to apply and clean up, especially when compared with other ‘heavy-duty’ adhesive primers on the market. It dries very quickly, which is excellent, but it can make it tricky to work with. Once you have applied it, be careful not to touch the primer until it has properly cured or it will peel.
If you are trying to rescue wood that is in very poor condition, the INSL-X Stix Acrylic Primer is an excellent choice because it holds everything together well, allowing you to seal it with a coat of paint.
Painting Old Wood FAQs
Does Painting Old Wood Require a Primer?
Yes, you should always use a primer when painting old wood. In fact, it’s good practice to use a primer on all wood, even if it is new, unless the paint has a built-in primer already. Untreated wood has a lot of small imperfections and pores in it, and these soak up paint but they also let in moisture.
If you paint directly onto the wood, the finish won’t be as even and there will still be some small pores that let water in. The paint will start peeling and the wood will be prone to rot, especially if it is outdoors.
A primer fills all of the imperfections and creates a strong, moisture and rot resistant barrier. When you put the paint over the top of the primer, you cement that protective barrier and the wood underneath is completely free from moisture. It also stops any tannins and stains leaking out of the wood and degrading the paint.
All of the challenges associated with painting wood are amplified if the wood is old, so never skip the primer or you will end up reapplying the paint over and over.
Do You Need to Add Paint Over Exterior Primers?
Primer is not designed to be used as a substitute for paint. If you put it on an exterior wood project with nothing on top, it will not stand up to the elements as well as exterior paint. It might last a while, but it’s designed to be a base layer that helps the paint bond better. That’s why I recommend using one of these exterior paints.
It’s the paint that protects the wood from the rain and the UV rays from the sun. So, it is advisable to use a high-quality exterior paint over the top of your primer.
However, there are 2-in-1 products that contain a paint and a primer. If you are using these, you don’t need a separate paint, you just need a few good coats. It’s important to check the products you are using so you know if you need to paint over the top or not. Before painting or re-coating know how long it takes paint to dry outside first, adding a fresh coat too early can cause peeling and poor adhering paint problems.
Should You Add a Sealer Over Painted Exterior Wood?
No, you don’t need to use a sealer over painted exterior wood. Exterior paint is designed to be used outside. It has additives that make it water-resistant and stop it from fading in the sun. When applied correctly, with a good quality primer underneath, the paint provides enough protection for the wood.
Sometimes you may want to provide a softer feel to the painted wood and using a sealer can help, but it will also keep the paint in good shape. See our article on how to seal painted outdoor wood.
Should You Sand Old Wood Before Priming?
Sanding is an important step, in most cases. Before you prime the wood, you need to prepare the surface properly by removing old paint, getting rid of dirt, and clearing away mildew. Anything that will stop the primer from adhering properly needs to be stripped off before you prime or paint the wood.
But when you are working with old wood, you need to be careful that you don’t damage it any more than it already is. If you sand brittle wood too much, you could take large chunks of wood out and it will be beyond saving. In this case, sand gently to remove any loose paint flakes but don’t be too rough.
Another thing to watch out for when sanding old wood is the potential health risk associated with old pressure treated wood. Read all about them in our safety sanding tips guide here.
Can You Pressure Wash Old Wood?
Pressure washing old wood can be an effective way to clean it up before you prime it, but you have to be careful. If the pressure is very high, it can damage the wood, especially if it’s already in poor condition. Ideally, you should pressure wash softwoods at 500-600 psi and hardwoods at no higher than 1200 psi, but if the wood is old, set the pressure even lower.
Sometimes pressure washing a wood deck the wood becomes fuzzy. To quickly answer why, it is that the old decking is weaker and the fibers will get pushed upwards from the pressure.
After pressure washing wood, make sure that it is completely dry before you prime and paint, or it won’t adhere properly.
Final Thoughts
Priming is crucial when painting old wood because it hides the imperfections and holds everything together. It also creates a good surface for painting and helps to avoid mildew. All of the primers on this list will help you bring old wood back to life instead of replacing it, just make sure that you take the time to apply it properly.
Jamie is the founder of The Backyard Pros. When he was 15 years old he started working at a garden centre helping people buy plants, gardening products, and lawn care products. He has real estate experience and he is a home owner. Jamie loves backyard projects, refinishing furniture, and enjoys sharing his knowledge online.