How Long Should You Wait to Stain Pressure-Treated Wood?

painting over treated wood

If you buy something through our posts, we may get a small commission. Read more here.

Pressure-treated wood is an excellent option due to its minimal aging effects and insect-repellent nature. However, an extra layer of protection through staining must be done to maximize its benefits. 

Our professional woodworkers will explain how long should you wait before staining pressure-treated wood as well as essential application tips.

Does Stain Protect Pressure-Treated Wood?

Staining is recommended to protect pressure-treated wood. Since this type of wood is porous, external factors like rainwater, dew, or snow can easily penetrate the material. Without staining, the wood will be prone to swelling and will shrink once it dries. 

treated wood

This pattern of swelling and shrinking can cause the material to split and also result in splinters, cracks, and other blemishes. Staining can also protect pressure-treated wood from UV rays that can cause fading, discoloration, and warping over time.

How Long Should You Wait to Stain?

Wet Pressure-Treated Wood

Pressure-treated wood undergoes a process in which preservatives are absorbed in the wood. Therefore, it is important to wait for just the right time to start staining—not too early, but also not too late. 

For wet pressure-treated wood, drying can take months. But a general rule of thumb is around 90 days after the project completion. External factors such as the weather and general environment can affect how quickly it dries. The best way to tell if the wood is ready to be stained is to test it.

Kiln Dried Pressure-Treated Lumber

Unlike wet pressure-treated wood, kiln dried pressure-treated lumber can be stained at least 72 hours after the treatment using oil or a water-based stain. 

Kiln Dried Pressure-Treated Lumber

It is important to note that the wood has already been kiln-dried at the lumber yard. Indicators “KDAT” or “ADAT” are usually stamped on the lumber. KDAT is “Kiln-Dried after treatment”, while ADAT is “air-dried after treatment”.

How to Determine if Pressure-Treated Wood is Dry and Ready for Staining

A few droplets of water on the pressure-treated 8/4 lumber can determine if it is dry enough and ready for staining. If the drops clump instead of being fully immersed, you would need to wait for a few more days. If it absorbs into the wood instantly, then it is ready to be sealed or stained.

What Will Happen if it is Stained Too Early?

If pressure-treated wood is stained too early, the staining material will be unable to successfully adhere or absorb to the wood and will result in a waste of resources. 

treated lumbers

Moreso, the protective benefits of the stain on the wood won’t take effect, so you would have to redo the entire process completely.

Which is the Best Stain for Pressure-Treated Wood?

There are a variety of options when choosing a staining material for pressure-treated wood. 

Water-based treatments are easier to work with and are less toxic. However, it may not fully adhere to the deeper grains of the wood. You may also choose between colored or natural-look treatments.

Our pro woodworkers recommend an oil-based stain for pressure-treated wood. Oil-based stains are their certified go-to option when sealing exterior wood because these are water-resistant and can thoroughly absorb well into the wood grains. 

Additionally, oil-based stains also offer a uniform finish and will not leave unsightly lap marks. Compared to water-based stains, the dry time of oil-based stains is considerably longer so you have more time to blend and even out the brush strokes.

painting over treated wood

It is also vital to know that you will need to apply more than one coat for certain areas that will need more stain, like the ends. Therefore, when selecting the best stain for pressure-treated wood, look for a decent amount that will do the job completely.

Also, you may want to opt for environmental-friendly and safe brands. Volatile Organic Compounds (VOC) [1] are toxic and should be used while wearing protection like a cotton mask or respirator to avoid inhaling harmful fumes.

Is it Better to Stain or Paint Pressure-Treated Wood?

Our team highly suggests staining rather than painting when it comes to pressure-treated lumber. This is because paint rarely adheres completely to pressure-treated wood. 

Similarly, wet lumber also hinders how the paint sticks to the wood. The preservatives ingrained in pressure-treated wood make it more difficult for the paint to bond. Thus, staining is recommended as painting will require extra effort to achieve.

FAQ

What is the green stuff on pressure-treated wood?

The green stuff on pressure-treated wood is caused by chemical reactions between the preservative components and the wood. Copper, the most widely used element in wood preserving, creates a green stain on the wood.

Conclusion

Staining is highly beneficial for pressure-treated wood for its protective properties against decay and damage. Fortunately, it can be easily done and all you need to do is wait until the wood fully dries. 

If done well, it will elevate your fence or deck’s overall aesthetics. We hope this guide has explained the waiting period for staining pressure-treated wood.

Robert Johnson is a woodworker who takes joy in sharing his passion for creating to the rest of the world. His brainchild, Sawinery, allowed him to do so as well as connect with other craftsmen and women. He has since built an enviable workshop for himself and an equally impressive online accomplishment: an extensive resource site serving old timers and novices alike.
Robert Johnson