Follow us on Pinterest
Welcome, Guest! Log In  |  Join Now

Tricks for Treated Lumber

Pages in this Story:
A Chemical Bath Starts the Process
Some freshly pressure-treated
lumber holds so much moisture
that puddles form around the
heads of driven fasteners.

A Chemical Bath Starts the Process

Wet and warped

The new breeds of PT lumber still start out as stacks of Southern yellow pine placed into large, sealed vats where air is evacuated and the preservative chemicals are introduced. The low pressure draws the chemicals into the sapwood. Because there is little chance for it to dry between its chemical bath and the time it hits the home-center shelves, PT lumber can have a moisture content percentage into the low-to-mid 20s. (Compare to kiln-dried hardwoods that average 6-8 percent.) Once left in your shop or a sunny spot, the drying--and the warping--begins.

The best approach to counter this: Let the wood acclimate outdoors in the shade for several weeks; then fasten it firmly in place with screws. One common mistake for beginning deck-builders is to leave a gap for drainage between the decking boards. This strategy isn't necessary for PT lumber; the shrinkage during drying will provide all the gap necessary.

Continued on page 3:  Safety


Comments (2)
benewah67 wrote:

where do you find .60 treated deck material

1/4/2012 03:53:16 PM Report Abuse
TXwoodrat wrote:

Always check the number on the label stapled to the wood, .20 Won't last long. Most big box stores only carry .20. If you want your treated lumber to last any length of time get .40 or above. I only buy marine grade .60 when I buy treated lumber. Landscape timbers are all rated .20, so expect to replace them much sooner than you would think. Note that the .20 label says "not for ground contact," but these are "landscape" timbers so does that make sense?

6/15/2011 12:16:16 PM Report Abuse

Add your comment

You must be logged in to leave a comment. Register | Log In

Please confirm your comment by answering the question below and clicking "Submit Comment."


Connect With Us
  • Recent Posts
  • Top Posts
See More >