Kiln Dried After Treatment
What is KDAT Lumber?
Kiln-Dried After Treatment (KDAT) wood is treated similarly to "green" or "wet" wood, but with one crucial difference: it undergoes an extra drying step in a kiln after being pressurized with chemicals. Using controlled temperatures, this process reduces the moisture content by as much as 80%, creating a much drier piece of wood. This minimization of moisture mitigates problematic characteristics like warps, cups, checks, and shrinking that are common with traditional "wet" lumber, which can take eight months to a year to dry naturally.
Why Southern Pine is the Best Species treated wood.
Southern Pine has long been the preferred species for pressure treatment, making up about 85% of all pressure-treated wood produced in the U.S.. Its unique porous cellular structure permits a deep and uniform penetration of preservatives, allowing the species to handle changes better than most.
Southern Pine provides superior structural integrity and stability:
- High Density: It boasts the highest specific gravity among all common structural lumber species, resulting in superior fastener-holding power and load-bearing capacity. Dense lumber must meet specific SPIB Grading Rules based on the number of annual growth rings per inch and the portion of "latewood".
- Stability: Dimension lumber 2" and less in thickness must be dried to a maximum moisture content of 19%, minimizing shrinkage and providing long-term stability. Southern Pine is more stable than Oak over time and handles stressors much better.
It can be painted, stained, or sealed immediately without waiting.
Even drying minimizes issues like cups, warps, checks, and shrinks.
It is easier to handle, cut, and plane, and is lighter than "wet" or "green" treated lumber.
It has more nail-holding and screw-holding power.