Pressure treated wood is amazing for any outdoor projects. This wood has been treated with chemical sealants before it was placed in a pressure chamber, hence the name, to force the chemicals deep into the fibers of the wood. This process of sealing the wood makes it very resistant to the elements and to certain types of bugs but it also makes it kind of hard to paint. So in this article, I will go a little more in-depth and try to explain how to paint pressure treated wood properly and permanently.
In short, to paint pressure treated wood you have to clean the wood from any dust or dirt with some soapy water and let it dry for a couple of weeks. Then you have to apply some primer for outdoor use. Let the primer dry and then paint your pressure treated wood with the color of your choosing.
So these are the basic steps of painting pressure treated wood but there are a couple of more small things, that you should watch out for before you actually get to paint your pressure treated wood.
If you are not careful or patient enough then your paint job may not turn out as expected or the paint may chip off or fade over time.
I will start by explaining what pressure treated wood is and how it is made so that you can better understand why it can be challenging to paint it.
Then I will explain exactly how to properly paint it in simple steps. And finally, I will answer some frequently asked questions.
So let´s get started with painting pressure treated wood!
What is Pressure Treated Wood and How is it Made?
Pressure treated wood is a cheap alternative to naturally element resistant wood types like cedar or redwood. It is widely used for a lot of outdoor projects but there are some projects, where you should not use it even if it is cheaper. But before we get to that, we will first take a look at how pressure treated wood is made.
Pressure treated wood is made by soaking the wood in a liquid preservative, in the Us that preservative is mostly alkaline copper quat or ACQ.
Then the wood is placed in a pressure chamber to force the chemical into every fiber of the wood. This will make the wood very resistant to fungi, bugs, rain, snow, and pretty much anything that may harm the wood outside.
This method of sealing, however, is also the reason why painting pressure treated wood is so difficult. The chemicals will pretty much keep anything from sticking to the wood, including paint. But don´t worry, there are methods to paint pressure treated wood despite the chemical seal.
As I mentioned above, pressure treated wood is great but you should not use it for everything. Even though the chemicals are bound to the wood they can still migrate into the earth or they can be washed off in small amounts by water. So if you plan on building a raised garden bed, for example, then pressure treated wood is probably the wort choice for it.
You can use pressure treated wood for outdoor furniture or decking but you should not use it close to any plants especially if they are vegetable plants, that you plan on harvesting. There is a great article from “fine gardening” about using pressure treated wood and its disadvantages when used for gardening. You can read it right here.
How to Properly Paint Pressure Treated Wood
So now that you know how pressure treated wood is made and what you can use it for it´s time to see how you can properly paint it.
Clean the Pressure Treated Wood and Let it Dry
Before you can start painting the wood you have to clean it first.
Simply use some soapy water and a towel to clean the wood from any dust or dirt, that might be on it. This is important because if you don´t clean the wood the primer may not stick to the wood as good as it otherwise would.
After you cleaned the wood you have to let it dry for a couple of weeks. Yes I know, that sounds like a very long time but the wood has to be completely dry before you can properly work with it. Unfortunately pressure treated wood takes a very long time to dry completely. Depending on the type of wood it can take up to a month.
You can easily test if the wood is dry enough for priming by dripping a little bit of water on the surface of the wood. If the water soaks in the wood, then the wood is dry enough but if the water stays on the surface in forms of drips or if it takes a long time to be absorbed then your wood is not dry enough yet.
Prepare the Pressure Treated Wood with the right Primer
Before you can paint the pressure treated wood you first have to prime the surface of the wood with a primer.
The primer will stick better to the wood itself than any paint and it will at the same time create a perfect surface for the paint to stick to.
Be sure to use a primer, that is meant to be used outside. You can buy a paint primer at your local hardware store or right here on Amazon.
Apply an even layer of primer on the wood and try to cover every part of the wood as good as possible.
Follow the instructions of the primer before you apply it just to be sure. Some primers require you to lightly sand the wood before you can apply the primer. So make sure to check the instructions, just to be sure.
Let the primer dry. Depending on the kind of primer you are using this can take a few hours or a whole day.
If you missed a spot or if the first layer wasn´t enough then you can easily apply a second layer if you feel like it´s necessary. Some Primes even require you to apply a second layer although this is quite rare.
Paint the Wood
And now finally you can actually paint the wood.
I recommend using latex paint because oil-based or water-based paints won´t stick well enough to the primer and will eventually wash off if you don´t seal them to protect them from the elements.
Even though you can paint wood with acrylics I would not recommend it for wood, that is going to be outside.
You can buy latex paints in your local hardware store or here on Amazon. I recommend latex paints from Rust-Oleum. They are quite cheap and I had really good results with them. The satin finish looks really good but you can get a shiny finish as well.
Try to apply the paint as evenly as possible and apply at least two thin layers to get a good smooth finish. Let the paint dry completely in between layers or you may end up with weird looking darker spots.
You can use a paintbrush or a roller. Depending on your project, you may even need both.
A paintbrush is great if you have a lot of hard to get corners or a lot of smaller areas where a roller can’t get to easily.
A roller, however, will make it easier for you to apply the paint evenly.
I usually use both. A roller for larger surfaces and a paintbrush for the hard to get to parts of my projects or if I want to add some detail to a project.