My understanding:
S-Dry = air-dried to a moisture content of 19%
KD = kiln-dried to a moisture content of 15%
Home Depot’s understanding (went to two stores):
S-Dry = KD
The sign says KD, there’s a little sticker that says KD/DF on each board, but they are stamped S-Dry.
Any problems using S-Dry in remodeling?
Replies
I think the 'S' stands for somewhat
S-Dry=Somewhat dry
<G>
or Sun dryed
Or "Sometimes"
I believe "S-dry" means is surfaced after it's dried.
I don't think you can buy framing lumber anymore that's surface dried. That want to keep it moving through the mills, so they kiln dry everything.
If you are successful, you will win some false friends and some true enemies; Succeed anyway. [Mother Teresa]
I always thought "S-Dry" meant "surface dry" too, Taylor. But then just the other day, Sphere told me it means the boards were surfaced when dry vrs "S-Grn" (surfaced green). And I don't have any reason to doubt what he says.
Now. I THINK for something to be stamped "KD" it has been taken down to 6-8%, then might have absorbed ambiant moisture before you buy it. But that might be hardwoods, and framing lumber might be more like 18% maximum or something.
It's all very confusing and more than I can remember day to day.
As for your question about suitibility for remodelling, I remember lively coffee break debates about the merrits of framing with green DFir vrs KD hemfir. The green proponents used to argue that the framing in a new house had time to dry out before it was covered with wallboard. I'm not saying they were right, I'm just throwing out an argument I've often heard. It's something to consider if you are remodelling a small space and are sealing the framing up right away.
Used to be we had to chose between the stability of KD or the strength of DFir here in the Pacific Northwet. These days we get the best of both as more and more yards stock KD DFir, but we usually pay a bit higher price for it. I try to use DFir for studs, joists and rafters and hemfir for plates (doesn't split as easilly).
Edited 9/29/2004 9:00 am ET by jim blodgett
Yeah thanks, I read Breaktime archives where consensus was KD for remodelling, S-Grn for new, I guess you take your chances with S-Dry. Though last load of KD 2x4, 7 of 12 pieces were too bowed to be useful. Lesson: don't have KD delivered, go pick it out.
Best I can figure, perhaps HD supplier kiln-dried the lumber to 19% instead of 15%, but calling it KD in the store then seems like misrepresentation....and that's why they (or their supplier) don't want to stamp it as KD.....
HD employees, feel free to clue me in on what is going on.... Is it 15%, and if so why isn't it stamped KD?
KD and S-DRY are the same thing.
DRY in this case means 19% (or less).
Wood at below 20% is not subject to rot and mold.
But it still has some drying to reach EMC.
Here is what Paul Fisette has to day about it.
http://www.umass.edu/bmatwt/publications/articles/wood_myth.html
I stand corrected.
Thanks for the link, that article was very informative.
"I THINK for something to be stamped "KD" it has been taken down to 6-8%..."
I'm certain that's not true. Lumber can be dried to virtually ANY moisture content. Much of the lumber we get is stamped "KD19", meaning it's dried down to 19%.
There's more about it here:
http://www.southernpine.com/moisturecontent.shtmlI'm not completely worthless. I can be used as a bad example.
KD= Knock Down...
you'll have to KD yer remodel after the way that stuff of their's changes shape..
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming
WOW!!! What a Ride!