How long will buried pressure treated wood last?

Asked By: Iuri Linnewedel | Last Updated: 31st May, 2020
Category: hobbies and interests woodworking
4.3/5 (1,713 Views . 45 Votes)
The Forest Products Laboratory and other research groups have shown that treated wood stakes placed in the ground for more than 40 years remain rot-free. But young pressure-treated decks, many less than 10 years old, are being shoveled into landfills.

Click to see full answer


In respect to this, will pressure treated wood rot if buried?

Pressure-Treated Wood Makes the Grade Pressure-treated wood in contact with the ground needs the most protection, and will rot in just a few years if you use the wrong grade. If your wood will touch the ground or be buried, you should get the highest grade you can, up to .

Beside above, do you need to seal cut pressure treated wood? Whilst treating or sealing any cut ends is important with any Treated Lumber product, maintaining a sealed end is most important when applicating Pressure Treated lumber in-ground, such as Fence Posts and Landscaping / Retaining Wall.

Subsequently, one may also ask, how do you protect pressure treated wood underground?

Thoroughly coat the lumber with water sealer made for wood. Using a pump garden sprayer, spray one coat onto dry lumber. Allow the sealer to soak completely into the lumber grain, and allow two hours between coats. Apply the second coat of sealer to the lumber with a roller or brush.

Why is my pressure treated wood rotting?

has rotted is due to a fungal issue. The fungi that cause this are very small organisms that move into the wood and feed on it over time. This causes the pressure treated wood to decay and soften which then turns into rot. All kinds of fungal issues basically create the same problem: rot.

23 Related Question Answers Found

Can pressure treated wood be placed in the ground?

To start, pressure-treated wood is softwood lumber, typically southern yellow pine, that's been chemically treated to resist rot, decay and termites. Lumber designated for "Ground Contact" can be placed directly on or in the ground.

Do termites eat pressure treated wood?

Pressure-treated wood is resistant to termites, but make sure that there's no contact with soil. Pressure-treated wood is wood that has had a chemical preservative forced into the pores to form a barrier that resists decay and wood-eating insects like termites and carpenter ants.

How long will non pressure treated wood last outside?

Some say that untreated 2×4's can last up to two years before showing signs of rot and others say it can last even longer. When deciding if you should you use an untreated 2×4 it depends greatly on the application, how much weather and sun it's exposed to and if it's making ground contact.

Can you pressure treat your own lumber?

Untreated wood like pine will only last a year or two if it is touching moist ground. Pressure-treated lumber is wood that has been immersed in a liquid preservative and placed in a pressure chamber. The most common chemical used to treat lumber used to be chromated copper arsenate, or CCA.

Will wooden posts rot in concrete?


A: Actually, your point is well taken. Simply setting the posts in concrete does create a condition that will accelerate rot in the bottom of the posts. With pressure-treated posts, the rot will be slow. Concrete should be poured around the post - no concrete under the post.

How do you protect a wooden post from rotting in the ground?

How to Protect Wooden Fence Posts From Rotting
  1. Remove the wood fence post from the ground.
  2. Dig a hole with a shovel about 10 inches beneath the area where the fence post will rest.
  3. Paint with a paintbrush the entire wood fence post with a waterproofing sealant intended for exterior wood, such as decks and fences.

How do you keep wood from rotting in the ground?

To treat your post, soak the bottom foot for 15 to 20 minutes in a large bucket of wood preservative containing copper napthenate. After your post has soaked thoroughly, use a brush to apply a thick layer of preservative on the bottom 2 feet. Make sure to let the post dry overnight before setting it into the ground.

How do you keep treated posts from rotting?

Tamp down the gravel. You can use concrete, if desired, but the moisture in the concrete can sometimes cause wooden posts to rot more quickly, while the gravel allows water to drain quickly away from the fence post and into the soil.

Can treated lumber be buried?


Use Properly Treated Wood in Ground Contact. It appears that many of these deck projects included Above Ground Use treated wood in direct contact with the ground, and in some cases these materials were even buried into the ground or backfilled with dirt.

Should deck boards have a gap?

The goal is to have about an 1/8-inch gap (the diameter of an 8d nail) between boards after the decking has dried to its equilibrium moisture content. If the decking is installed wet, as is often the case for pressure treated material, it is best to install the boards tight, letting gaps form as the wood dries.

Can you put a sealer on pressure treated wood?

Sealers & Finishes for Pressure-Treated Lumber. Although treated wood is protected against decay and termite attack, the application of a water-repellent sealer to all exposed wood surfaces is recommended upon completion of construction. Treated Southern Pine lumber will accept a finish similar to untreated material.

Is pressure treated lumber treated all the way through?

Generally, yes. Most wood that is treated with a waterborne treatment is treated through its entire thickness to varying levels of retention. Ripping treated dimension lumber and putting it in contact with concrete is nothing to be concerned about.

When can I seal pressure treated wood?

A newly built deck that uses pressurized wood will need time to dry completely before a sealer can be applied. The chemicals used to treat the wood leave moisture behind, and depending on the climate, it can take anywhere from a few weeks to a few months until it's dry enough to seal.

Is pressure treated wood harder to cut?


Dry it Out. The process that makes treated lumber protected against insects, water and mold also add a lot of moisture to the wood. This moisture can make it difficult for someone to cut the lumber. The added moisture can cause the saw blade to slip, the cut to not be clean or for the wood to splinter and chip.

Should you paint pressure treated wood?

Besides making sure your pressure treated lumber is dried out from the treatment process, it's also essential not to paint any wood if it's wet from rain or snow. Do your painting during warm, dry weather and low humidity conditions. If your lumber is outside, wait at least a month after the last rain before painting.

Does paint stick to pressure treated wood?

Pressure-treated lumber can take weeks or even months to dry. Once the wood absorbs water on the surface, it's read for paint. Our experts recommend priming with a latex primer and a compatible exterior latex paint, also known as water-based paint.