Does Pressure Treated Lumber Shrink

Even products that are sealed and treated are going to shrink. This most typically occurs across the width of boards, so builders should take into consideration the fact that their lumber will shrink over time. Additionally, as part of the drying stage of treated wood, the boards will crack, also referred to as checks.

How long does it take for pressure treated wood to shrink?

Over time, most treated lumber will shrink slightly across its width as it dries out. Take this small amount of shrinkage into account when laying decking or fence boards. After being outdoors for six to 12 months, treated lumber will develop cracks, called “checks,” along the surface of each board.

Does pressure treated wood warp less?

Treated wood doesn’t always twist/warp/shrink, but in my experience more often than not it will to some degree. For something small like window planter boxes etc. I would use non-treated lumber and stain or paint with a quality exterior grade product.