Can You Use Non Pressure Treated Wood for a Deck?

Can You Use Non Pressure Treated Wood for a Deck?

Can You Use Non Pressure Treated Wood for a Deck? Yes, you can use non-pressure treated wood for a deck.  The downside is that it will last between 15% and 50% fewer years compared to pressure-treated wood, and it’s still advisable to treat the wood with weatherproofing and stain.

If you plan to use non-pressure treated wood for your exterior projects, it must require protection from different elements. Wood is a long-lasting and robust material, and you can use it in a wide range of areas. No protection and too much exposure to moisture and insect activity may cause serious problems.

The question, however, is: can you use non pressure treated wood for a deck? Let’s find out in the following lines.

Non Pressure Treated Wood for a Deck

You can still use non-pressure treated wood for your outdoor projects like a wood deck or shades. To increase these structures’ lifespan, you need to take some protective measures so they can serve you as long as possible. For your outdoor project, you can use stain, wood sealers, and paint to protect your untreated wood.

Suppose you are using untreated wood outside and unable to secure your structure with the necessary protection like stain and sealer. In that case, it will wear out quickly, and you’ll have to incur extra cost on repairs or re-installation.

Threats to Non-Pressure Treated Wood 

If you have planned to use non-pressure treated wood for the deck, you need to understand the possible challenges you will face in the process. You can face different issues that will badly affect and devalue your structure. These include:


Water is the biggest threat to wood’s survival. If your wood gets wet, several issues can arise, including decay, rot, and molds growth as time passes. By merely using an outdoor wood sealer, you can protect your outdoor non-pressure treated wood from water and avoid damages.

You may easily find high-quality sealers available in the market. Wood sealers are waterproof and will do excellent work against water infiltration.


You may find several benefits of sunlight, but it has some side effects on both pressure treated and non-pressure treated wood. As we know, the sun produces ultraviolet rays, which might be dangerous. They will quickly drain the entire oil from the wood. 

You will notice the wood structure starts losing color and fades once the oil is eliminated from its structure. 

But, I have a solution for it. You can use stain with UV light blockers to protect your wood against the sunlight.

Untreated Wood Species for Deck

I’ve observed that some people use pressure-treated wood for their outdoor decks because it increases the lifespan of the structure. But you can find some species of wood with naturally occupying chemicals even if they’re installed untreated. They help in harsh weather and also protect against insects. 

Such wood species are:


It is initially used for boat building and can stand in any weather conditions and an excellent choice for outdoor projects, which is affordable.


Redwood is famous for its ability to stand against elements and for its beautiful colors, which become a reasonable choice for outdoor projects. But due to a shortage of material, it is not readily available in the stores.


Cedar is readily available and famous for its natural beauty and can stand against insects and prevent decay. It is brittle and may split when nailed or screwed.    


This wood grows in southeast Asia in wet and soggy soil. Cypress wood comes in different colors ranging from light yellow to dark reddish-brown. It has an average resistance to decay and is used for fence posts and marine applications like boat docks. Cypress wood is stable and will not crack or split easily. Also, it is widely used for cabinets and interior trim.

Untreated outdoor wood must benefit from regular application. Like stains, sealers, and paint to maintain the beauty and increase their lifespan.  

These wood species work well with protective agents like sealers, making themselves perfect for exterior usages like deck and shades. On the other hand, some other wood species like alder, pine, and hemlock are weaker, and if left untreated and used outside, they have high rates of rotting. 

The Lifespan of Non-Pressure Treated Wood Outside

Non-pressure treated wood can take from 5 to10 years. This time length is based on factors such as how well your maintenance is, sunlight exposure, and weather condition in your area.

Usually, I don’t recommend using untreated wood on decks because many other factors can reduce its lifespan. These include termites, water, and infestation by microorganisms.

On the other hand, pressure-treated wood is also used in many cases, simply because its lifespan is longer – up to 15 years.

How to Protect Non-Pressure Treated Wood From Water

For protection purposes, there are three proven ways to water-proof a non-pressure treated wood. Here they are:

  • You can use linseed or tung oil to make a protective and hand-rubbed finish on the wood’s surface.
  • You can use varnish, polyurethane, or lacquer finish.
  • Using semi-transparent deck stains will make your non-pressure treated wood waterproof.

How to Seal Non-Pressure Treated Wood

Suppose you are planning to use non-pressure treated wood for an outdoor project. Follow these steps:

  • Before you go on to seal the wood for a longer lifespan, properly inspect the wood. Make sure it is good condition throughout, and there should be no sign of rotting  
  • You need to ensure that the wood is completely dry so that you can prepare it for sealing. For this purpose, leave it outside for some time, making sure that the surface gets dried complete. 
  • Inspect the wood and make sure there are no air traps inside. Otherwise, the seal won’t be able to hold ground. 
  • Your wood will be ready to accept a top sealing coat after 48 to 72 hours. You need to use the right method like a brush to apply the sealer over the wood’s surface.
  • There are plenty of wood sealers available in the market. Before applying, you must read the manufacturer’s instructions and strictly follow them.
  • After the first coat of the sealer on the wood, leave it to dry for some time. Once it dries, apply the second layer over the first and leave it to cure before using your surface.


You can use Non-pressure treated wood for your deck project. However, it depends on the type of wood you select for your exterior project. With the information above, it will be easier for you to choose the right wood type for your decking project.