Est. 1998 — 27 years of woodworking knowledge
Humpday Triviola
Thomas Skaggs, Foothills of Mount Level
Ok, you have a building project on your hands. Mostly outdoor or exposed wood is the nature of the job. Now to get your materials. It might be a good idea to check with the USDA for a EMC recommendation.
Why?
Re: Humpday Triviola
John Veerkamp
Is this another example of your dry sense of humor?
I think John has it, but just in case...
Lee Schierer McKean, PA
Only a balanced person with a dry sense of humor will get the golden uni today.
Lee
Re: I think John has it, but just in case...
Ken Oakley-Sunny St. Cloud, Fla.
Guess that leaves me high and dry---
John first in....answer
Thomas Skaggs, Foothills of Mount Level
John was the first in with knowing that EMC relates to equilibrium moister content.
The MC of lumber can soar when is stored at a lumber yard without a protective cover and/or stacked over wet ground. Lumber stored in a very humid environment like next to the ocean can sponge water too. A KD stamping means very little if the lumber has been left sitting in the rain at a distribution center, reload yard, retail yard or building site. Spot check the lumber you are using with a moisture meter. It is important to match the MC of the wood you are using with the equilibrium conditions it will see in service. The in-service MC or equilibrium moisture content (EMC), can be benchmarked to relative humidity:
� RH 25% ~ MC 5%
� RH 50% ~ MC 9%
� RH 75% ~ MC 14%
� RH 90% ~ MC 20%
Wood used inside of homes as finished trim, cabinets and flooring, should be installed at a MC close to 8%. Wood used in exterior applications is a different story � it depends on where you live. In New England 14% MC is a good target. In Tucson, a 6% MC would be a better mark. The USDA Forest Products Laboratory in Madison has a pamphlet (FPL-RN-0268) listing outdoor EMC�s for about 350 cities worldwide.
Well done John, et al.