How Does Moisture Affect Lumber?

Many different factors influence the grading of softwood lumber. One of the largest players in lumber’s grade, surprisingly, doesn’t involve the lumber’s cutting process or its number of knots. Instead, it concerns moisture. How does moisture affect softwood lumber? Oswald Wholesale Lumber is an expert dealer of  lumber near you and we have the facts on how moisture impacts softwood lumber grading.

Determining moisture content

Any association that grades lumber must disclose the moisture content that was present in the wood at the time it was turned into lumber. This is essential since a piece of softwood lumber will shrink during the surfacing process. Moisture can affect how much or how little it shrinks, which in turn affects how the lumber can be used for a project or on a job site. Lumber with a high moisture content is optimal for new construction jobs since it’s generally cheaper. Moisture-heavy lumber is not likely to split easily when nailed and shrinks at a steady pace. On the other hand, some jobs require drier wood, such as remodeling projects. When deciding which lumber will work best for your particular projects, it’s best to the pros at a wholesale lumber business or a building supply in Columbia, SC.


This stamp indicates that the lumber was surfaced in a green condition. In other words, the moisture content was above 19%.


S-Dry means that the lumber is surface-dry and that the lumber’s moisture content was less than 19%.


When lumber has this stamp, it means that the moisture content in the lumber was less than 15%.


Lumber with this stamp has been kiln-dried and completely heat-treated. This heat-treating process destroys fungi spores and insects, which both lead to lumber decay. Shipped lumber must be KDHT stamped.

Are you looking for lumber near you in the Batesburg-Leesville or Lexington areas? Visit Oswald Wholesale Lumber where you can view our high-grade selections of both hardwood and softwood lumber. See how our building supply in Columbia, SC can help you find the right lumber for your projects.

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6707 Augusta Hwy.
Batesburg-Leesville, SC 29070-7604

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