Timber Framers Guild Forums General General Forum Questions amount of wood in stud frame vs timber frame

i am interested in this statistic. i read a couple times before, i think once in steve chappell's book that a stud frame uses more wood (board feet) than a timber frame. is this including the wood used in infill? i would like a straight stat like for every 1000 square feet of house a stud frame uses x BF versus x amount of BF for a timber frame. for the timber frame stat i would like amount of BF just as a raw frame and as a frame with infill. does anyone have this stat available? is it possible? kind thanks.

too many variables....
some stud frames are 2x6 and might even use 16" centers.
I've also seen 2x4 on 24" centers....
and some timberframes use 8x8's on 8' centers, others I've seen(like our old barn) have 10x10 posts on 20' centers......

However, If you have a timberframe book, say ted benson's first book, there is a more or less standard timberframe plan in there. you could pull out the board footage from that frame and call it ballpark.... Then if you take a 2x4 on 16" center or a 2x6 on 24" center stickframe and pull the board footage for the same size footprint as the benson frame(you would be wise to call up a truss company and get ahold of the current center spacing and design for the gang nail trusses) ... again that would only be a ballpark figure..

I echo Mark's opinion that there are too many variables to give you a rule of thumb or standard without knowing more parameters. There are many types of enclosure systems being used by timberframing companies all requiring differing amounts of wood. Conventional stud/fiberglass batt infill is only one of these. The mostly widely embraced enclosure system currently in use is SIP's.

To get even close you would need to define the enclosure system as well as the floor and roof system. Perhaps the only fair way of doing what you are asking is to base it on a single story home built on slab to minimum local structural code and with no architectural features or details.

If you do this and compare a conventional stick built home using lightweight trusses vs. a SIP enclosed timberframe with common rafters I suspect you could possibly see a savings of up to 25-30% in total BF of total lumber used.

Keep in mind that 99% of conventional homes are framed with softwoods. Pine, Fir, Spruce, or Hemlock. Total board ft. in a timberframe can be reduced by using stronger/smaller dimensioned hardwoods such as oak instead of softwood to acheive longer spans and handle greater loads.

Also remeber that from an environmental standpoint a timberframe home can be disassembled and reassembled or the timbers recycled. Conventional framing is for the most part single use.

Hope this helps.

I can recall two barn frames; one 24' x ~53' with a 5' knee wall, 14/12 pitch and eleborate roof system, and an ~ 32' x 46' Queen post truss barn which both went out with over 60,000 pounds of wood, for the frame alone.

My buildings are generally, pound for pound, far more wood intensive than most stick frames would ever be.

Though, there is another variable; Time. There are countless examples of timber structures surviving the ages, and none yet of Platform houses doing so. If it proves that the average, well-built, well cared for, timber frame can be expected to weather two centuries, and many more, How does this figure into the efficency in terms of wood usage versus a wooden structure which lasts far, far less, despite it's using fewer board feet?

Just some back-of-the-napkin calculations:

1-10x10 post = 100 sq in
1-2x6 stud = 12 sq in

So each post is equivalent to 8.33 studs.

At 16" on center, the studs will go 133" or about 11 feet. That's pretty close to the spacing you might use between 10x10 posts. Using 8x8 posts, the timbers come out ahead if the spacing is merely 7 feet. Granted this is the simplest case. I didn't address trusses or compare plates to girts, etc. But I think it's fair to say that you're "in the same ballpark" with repect to the raw amount of lumber consumed. Now to be fair, you also need to acknowledge that the timbers require bigger trees, and thus will take longer for the forest to replace, but I think that's more than balanced out by Timberbe's point: the timber frame is built to last for many generations.