I'm building a small timber frame cabin for a friend on Salt Spring Island, B.C. My friend is currently milling Douglas Fir timbers from the property for the project. We are looking for some advice on the minimum reasonable amount of time to 'season' the timbers before we start the joinery. We are comfortable with the consequences of shrinkage of green timber on the frame but are concerned about the impact of twisting after we cut and raise the frame. We are thinking 6-8 weeks. Also, what is the best way to store the timber during 'seasoning'. Thanks.

I think your timeline on "seasoning" (or is that curing) is correct....around 2 months. Steve Chappell's book "timberframers workshop" has a good section on this.
if you have your own mill and you are expecting this wood to react(spiral grain or whatever)then mill it a bit oversize and resaw it after curing.
I have good luck storing timbers outdoors under old steel roof sheeting(slabs from the outside of the timbers would also work), held down with rocks and timber end cuts. In my opinion, stack the timbers crown up with only two supports(1/4 way or less from each end), and carry the two supports up throught the pile in a plumb line.
Big sticks between timbers are a bonus(at least 2x2)
I had the pleasure this week of renovating our old combine barn into a timber barn, then piling it full of timber......open at both ends for easy tractor/loader access, it's a good feeling to see our timber in a well ventilated shelter.
-Mark.

Stacking long timbers with only two supports could be asking for trouble. Leaving the ends free to twist, rotate, bow, bend or flex any way they want isn't the best policy.
I've been criticized before by stating that I support my timbers every two feet on center from end to end, but I don't enjoy working with twisted snakes as much as others do.
At the top of this page is a search button, put in "storing timbers" or "timber storage" and all open forums and get some other views and read what has been posted before.
And evaluate your options based on your personal circumstances.
Good luck with your project.
Jim Rogers

Why season the timbers at all before cutting joinery?
Timber framing was created in relation to the use of hand tools and therefore freshly felled timber. Millions of Timber Frames from the 12th century on have been built utilising green wood and are still in use today.
I would assert that the selection of trees and proper sawing are much more valuable in reducing twist, and other defects than "curing."
If curing was to be used, it would be more appropriate to utilise before the timbers are sawn, since sawing them twice would take a huge investment in time and energy.
In my shop, I would begin cutting the frame directly after the sawing was finished. At the same time I would sticker them properly in all phases of the project, apply Anchor Seal to the end grain, and cover them with sheet metal or some other material that would not restrict air circulation. You could also just let them grey in the weather, preferably out of continuous direct sunlight.
On this subject; Jack Sobon's Built a Classic Timber Frame is an excellent resource.
-Collin

Speaking to the stickering issue, I beleive you have a point in the smaller timber, Jim. from 1x through 4x or 5x, using plenty of stickers is good. I was thinking of 8x stuff, where I think the stickers are more trouble than they are worth, unless you are building a very big and long term pile, perhaps with a ton of stone on top?
-Mark.

Thank you Collin. I'm glad someone else out there besides me thinks that "seasoning" timbers is a waste of time.
If you have received all your timbers for your frame from the sawmill, and you are starting to cut the joints, the last timbers you cut will most likely be somewhat "seasoned" by the time you get to them. And the first timbers you cut will be "seasoned" somewhat by the time you finish the last ones.
I personally don't intensionally season any timber, any length of time. If wood drys at the rate of 1" in thickness per year, how much drier is it if you let it "season" for a few months? Not enough to make any noticeable difference.
There are more important things to be concerned about in regards to cutting your frame then the amount of time it should be "seasoned".
And I still can't understand how less support to a pile of timbers is better.......

Thanks for the advice. I think I will stick with the 6 weeks and take your advice on the end seal and sheltering.