moisture content

[Skicat]

Does anyone have any info regarding moisture content at the time of manufacture and / or the time of delivery of wood products (mainly dimensional lumber) to a jobsite? I'm trying to estimate shrinkage and am having trouble finding initial moisture content values. Thank you.

 

[boo1]

see link:

http://www.hornerflooring.com/techguide/maintenance/moisturecontent.pdf

 

[MiketheEngineer]

If I remember it must be under 19% - closer to 15% is the rule. In service it should drop to 5-10% depending on ambient humidity and use.

 

[RARWOOD]

Most dimension Lumber, 2" in nominal thickness, is surfaced at the mill to the dry standard and would show S-Dry on the grade stamp.. The dry standard requires the material to be at a moisture content of 19% or less at the time of surfacing. So most 2x4's, 2x8's, 2x10's & 2x12's are at a moisture content close to 19% when they are surfaced.

Field studies have shown that S-Dry lumber averages around 15% moisture content by the time it reaches the job site. There is also a MC-15 standard that requires the material to be less then 15% at the time of surfacing.

Dimension lumber 3" to 4" in thickness and all timbers are surfaced green, with a moisture content exceeding 30% at the time of surfacing.

 

[Dinosaur]

Most low end lumber is KD19 or KD15. This stands for Kiln Dried to 19% moisture or 15%, respectively. Some is dried to lower values, but will likely cost a lot. I only see lower values in cabinet lumber and furniture.