Kiln Drying Pressure Treated 3x Members 1

[mzaitz]

Morning!

I have a project where we specified Pressure Treated (0.6CCA) 3x members for the girders and joists for a fixed pier (3x10 for joists, 3x12 for girders). Sizes were selected to support a Cushman. They are supposed to be Kiln Dried after treatment to <19%. The Contractor has come back with an RFI from the supplier that they do not recommend kiln drying 3x members because they outside of the wood will dry faster than the inside which will lead to more cracking, etc. What other options are there? If it is air dried then it will shrink and crack but it will shrink after it is partially constructed. Our relative humidity varies greatly (45% to 85% just for today) but no where could I find how long it would take for the wood to equalize with the environment. Any other options?

 

[dik]

Can you use double lams of 2x material... 2*1.5" = 3" as opposed to 2.5"? I seem to remember getting pressure treated, kiln dried, material in larger 'square or rectangular' sections not 3x though...

Dik

 

[MotorCity]

Where did the kiln dried requirement come from? You should be concerned with the moisture content at delivery, not how they were dried. If the wood is exposed to moisture in the constructed state, then the moisture content may be a moot point as it will change with the weather.