I am planning to build a timber frame barn and house on my farm in a few years. I am cutting the timbers myself. I have several types of trees available to work with, including various oaks, ash, hickory, cedar, pine and locust. What types of wood are preferable? I have a large cherry log that would make some nice timbers. Is it suitable (it would look nice) or should I keep it for furniture?
What sawing method will provide the best timbers? Will the best timber be from the center of the log or cut on either side or how?
I understand these heavy timbers will take several years to air dry. Are there any specific things I need to do for best drying (I am used to typical 1 and 2 inch lumber)?
Can you recommend a book?
From contributor J:
Box heart all beams. Air dry on sticks of suitable size due to weight of timbers. Off ground at least 16-18" and cover pile to shed rain. If you are using oak timbers, don't use metal roofing for cover, because water dripping from metal roofing will stain your timbers. Average drying time is 1" per year.
A lot of timber frames are built green. The older the timber the harder it is to chisel joints. Best timing is to raise frame in fall, enclose over first winter and spring, finish insides over summer and fall, then put heat to house second winter. This allows frame time to air dry while standing. This can help to reduce checking of timbers.
Hickory can twist a lot but can be used. Oaks are best for posts, as they are one of the strongest. Locust is good for pegs. Pine is good for any timber--some frames in the northeast are all pine. Cherry will make nice braces--I've seen that before. Some builders use all the types you've mentioned in the same frame. To each his own.
The Timber Frame Guild is your first stop and best investment. Also study old timber frame buildings in your area and copy and use the same construction and woods. The best book that I have used is Tedd Benson's first book. It leaves some gaps in some procedures and using the right joints to the imagination, but is a must have book for any timber framer.
I expect to use 6" posts so that would take 6 years to dry completely! (I have read that in other places as well.) I had planned to use railroad ties with clean boards on top for the bottom of the drying stack. I expect 2" lumber would be best for stickers in timbers. I use a drying shed with a metal roof. Should the stack still be covered? If so, with what?
"A lot of timber frames are built green." This shocked me. Timber framing is uncommon around here (Arkansas Ozarks) but I expected dry wood to be used. Doesn't the drying mess up the joints?
Actually raising/enclosing the structure in the fall and allowing to dry while standing sounds like a reasonable plan due to my time/money restraints as a rancher.
Since oak is one of the best and most available in my area, I will use it. I assume it is best if the timbers are completely clear (no knots). Does the type of oak matter much or are they all good for timbers?
I plan to buy 'Timber Frame Joinery and Design Workbook' from the Timber Framers Guild and am looking for one or two more.
Most timber frames are built green, as was mentioned before. It's not any fun to try and work joints into beams by hand when the wood is dry! It's much worse with oak or one of the other tough hardwoods. The joints tend to tighten up as the beams dry. Also, if you put the building up while it's green, the beams will tend to be held in place by the joints and therefore will be less likely to warp totally out of shape. What do you do if you dry your beams for 3-4 years, and when you go to use them, you find one with too much bow or twist? You can't use one green beam with a bunch of dry ones, and you probably don't want to wait another couple of years.
Yes, one beam per log. This makes each beam strong. Off center heart beams will or can bend, bow or twist when drying. To saw a box heart beam you have to measure from the heart to the saw table on each end and raise the lower end until it matches. Blocks, taper controls or whatever it takes, until heart is level with blade or table, whichever type of sawmill you're using, bandsaw or circular. Then you have to plan your last cut first. That is, if you're making a 6x6, your last cut is 3" off the heart, so don't cut any deeper than 3" off. From that point you add up the thicknesses of the other lumber you are making, such as 1" boards or 2" planks, to determine the starting cut. Once you've done this one, the first and second (adjacent) face, you don't have to block the third or fourth face as they are now aligned to the heart.
If you are drying these in a shed, no additional cover will be needed. But again, you don't want to wait 6 years. Plan on putting it up as soon as possible after you've finished milling the last timbers or other lumber necessary to assemble the house/barn. As to drying messing up the joints, you have to plan your joints for shrinkage (more learning here), then as said, the joints get tighter, (with proper planning).
Maybe you should start with the barn and learn from your mistakes there and do the house second. Some people do this to learn timber framing.
As to which oaks to use, clear or not won't matter much, although you don't want to use any with big branches near any joinery. You'll have to learn how to make “grade 2 or better” timbers. That is what should be used in timber framing houses and barns. Get a grade book and look up timbers 4" and larger and see what the specs are for sizes of knot per face. These grade rules will give you some ideas about quality of timbers needed.
Jack Sobon’s books are good, both of them. Steve Chappell’s book is another. With Tedd Benson’s book and these you should have a lot of good info to build a barn, then house.
I haven't read any detailed books yet so the 8x8 may be my choice. I do plan to build the barn before starting the house (it will be needed for convenient material storage) and will do some even smaller projects first. I have access to both a circle and band saw. I will try to use the band saw, as I cannot comprehend blocking the log with a traveling table. I will try to get clear oak beams.
I do plan to consult with others on the design before beginning construction of either the barn or house.
Building a timber frame is the most rewarding thing that I have ever done. I make my living in the wood business but I love to timber frame. If I could take off I would come up there and help you build it.
What tools are recommended? I prefer simple power tools. I do have a large tractor with a loader for lifting the frames. A neighbor also has a crane I can get.
I will use the cherry for furniture and trading stock. I will not be ready to raise the barn until next year (or so) and the house until the year after, so the logs I already have will be cut and sawn for other lumber (they fell mostly during our ice storm this winter).
2" framing chisel
1 1/2" framing chisel
5# rawhide cast frame mallet
wood maul(8x8 cypress block with a 2' cherry handle)
10" Skill Saw (Skill brand)
8" Skill Saw (Skill brand)
1/2" Dewalt Drill motor
2" auger bit
2" spur bit
1 1/2" auger bit
1 1/2" spur bit
1" auger bit
peg iron (for making pegs)
Start looking in pawnshops for power tools and auger bits. Antique stores for chisels and slicks. I spent about 5 years collecting my tools.
A rabbit plane has the cutting iron right out to the edge of the sole, so you can plane a 90 degree corner up close to the shoulder of a tenon.
I'm not sure what he calls a beam hand saw, but it's probably a long hand saw for cutting off beams that are bigger than the skill saw can cut.
A beam power plane is a handheld planer that can plane a beam smooth. Nice tool, but costs a lot.
His list is a good one.
Comment from contributor B:
The one problem that I have seen with boxed heartwood is that it twists more. True, it may be stronger, especially in long spans. The timber frame company that I work for (it is a large one) no longer will use any timbers that have heart in them. If sagging is a concern, consider using bigger timbers and larger knee braces, thus minimizing the distance of the spans. All this, of course, if you don't want beautiful square timbers to twist over the years as they dry.
On the issue of shrinkage due to drying, my eyes were opened wide about 20 years ago. I framed a house where the subfloors were green 16' 2" x 6" t&g fir. They were quite dry before the finished floor was installed. The shrinkage in the 16' length was less than 1/8" while the shrinkage across the 6" width was in many cases 1/4". The shrinkage depends on when the wood was harvested. The old time barn builders cut their trees in the cold weather when the sap was down. The wood dried faster and shrunk less while drying. I wouldn't timberframe a house using this technique, but I'm planning to build a quite large shop and I'm going to use 8"x8" timbers and connecting steel hardware. Not quite a real timberframe, but my tools won't know the difference.
In this method of timber framing, tenons and mortises are laid out and cut into timbers after a reference edge has been established. Needless to say, the number of joints required for a sizeable structure can add up very quickly, so efficiency comes into question at the same rate.
With this said, one must consider ways to speed up the process without adversely impacting the quality of the joinery. One sure way to improve joint cutting efficiency is to use either manually operated boring machines or a chain mortiser. Both machines greatly enhance your ability to make one of the most time consuming timber cuts - the mortise itself.
Finishing the mortises in your frame is generally left to your hand tools, but the removal of the majority of the wood in a mortise can be greatly enhanced through the use of either one of the aforementioned machines. I realize that this is an old thread, but it still may be of use to other aspiring timber framers in the future.