10x12 workshop

Hello everyone.

Ive just joined the forum and have very much enjoyed all of the great information.

I just read "Learn to Timber Frame: Craftsmanship, Simplicity, Timeless Beauty" by Beemer and am confused about layout and engineering. I was planning to build a basic hemlock 10x12 TF workshop and was planning to use 6x6 for the posts, plates and beams and use 3x5 for the bracing, rafters and joists. I plan to construct three bents so there is support in the middle of the top plate. Am I under engineering the building? This project will be a lot of work so I only want to build it once. In the book, Beemer builds a 12x16 structure and uses 8x8 for the foundation, 8x7 for the top plate and 3x6 for rafters and braces.

Any help will be very much appreciated.

Will reads and posts here fairly regularly, so he may well get to this post of yours pretty quick...

In the interim, I would offer the following, and Will (et al) can add there 2¢ if I have missed anything...

There is a number of reasons an author or workshop facilitator will employ larger timbers for such projects. It is usually a "first time frame" for folks...and thus...must offer a number of platforms for students to learn on and perhaps have some error in as well...

The larger sizes gives better margins from the point of view regarding engineering, as well as, to just "the feel" of working the sizes timbers (mean average) that many American Frames are often (not always) constructed from...

Size-wise, for a building you plane on constructing, the timbers could be even smaller (down in the 4x range for many of them) but the joinery system and layout would be completely different...

The question is, as your first timber frame, you may not have the skill sets to alter Will's joinery system he has for the specific frame illustrated in his book. It would be perhaps un-wise to alter sizing for a specific design without the direct input from the designer (Will) and/or seeking PE (professional engineer) approval for timber resizing and joinery alteration.

As a designer myself, I provide the frame designs engineered to be built as the plan states them. Alteration by the owner without assuming full liability themselves and/or seeking additional PE support is unwise most often....Unless one has developed the skill sets and knowledge base to do so...or...the plans give clear margins of size differential where alterations can be facilitated...Some designs and those illustrated in books come with these margins clearly stated...

Opinionated advice (mine included) here is just that "opinion" and could cover a large spectrum of experiences...good and not so much...within the craft.

Bottom line, proceeded with caution, and/or contact the author directly, or pay fees for PE resizing...I have seen dire events take place by fairly seasoned Timberwrights and General Contractors with decades of experience building "stick-frames" that attempt altering designs without knowing..." what they don't know..."

Good Luck and have fun!!!

j

Thanks for your spot-on comments, Jay.
Hemlock: There is a 10x12 option (with an addition) shown on page 141, and you only need two bents and can keep the original sizes. No snow load to speak of in Tucson so even better.
One problem with going to 6x6 posts is getting enough room for joinery where pieces come in from opposite sides at the same elevation, but two bents instead of three and staggering the joints gets rid of that problem.
Yes, a middle bent with tie beam would be good as much to keep the 6x6 plate from bowing out with roof spread (gets worse the lower the pitch) as much as gravity load support. Tie beam at 6x6 would probably be OK with braces under it and no loft.
Are the 6x6'x nominal or actual dimension? You might be losing another 1/2" if nominal from the lumberyard.

Hi Will,

I will actually be building the structure in Ontario (cottage)so I will have to consider snow load. If I follow the design on page 141 with the longer top plate, will I be able to lift the beam by myself? Im trying to design this so I can manage the pieces.
There is a sawmill 40 minutes from my place so the wood will be actual dimensions but I expect I will have to square them up losing some dimension.
So to get enough wood in my joints, then I should use the 8x8 post and beams to ensure I have a safe building?

Hello Hemlock,

It doesn't look like Will is at his desk...So I will give my best 2¢...




Your ability to lift a frame or frame members is solely dependant on your rigging skills and equipment. I have lifted solo multiple tons several stories into the air, but this is dangerous and critical skill sets.

Be very clear on your goals, the equipment's capabilities, and above all...take your time and pay attention to details...

This is not a topic even for several pages of postings on a forum...Seek help directly from a master rigger if you are not confident of these prerequisite skills sets to solo timber frame facilitation and raising.




No dimension need be lost unless you wish for some other reason of need and/or aesthetic...

Will brilliantly outlined his layout modalities within the reference tome. So whether using his illustrated systems or a mix of line, scribe and/or edge/mill rule systems of layout, the timber could be round and tapered, live edge, or out of square and your joinery still fit perfectly. This is about approach methodology and skill set within a layout system...and how effectively you implement design, layout, and execution of the joinery...




Yes...I believe that would be most prudent for your first frame...

Good luck, and don't hesitate to ask more questions...

Regards,

j

7x7 posts; no need for 8x8.

Thank you Will.

Would you recommend the addition of a middle bent? I would like to extend the top plate so that there is 12-18" of overhang on the exterior side to keep the weather off the building.

Thanks again.

Yes, as stated earlier:
"Yes, a middle bent with tie beam would be good as much to keep the 6x6 plate from bowing out with roof spread (gets worse the lower the pitch) as much as gravity load support. "

You could get by without a true bent, though, by putting a post under the middle of the plate for the gravity load (you probably should include a foundation support under the sill at that post, or beef up the sill), and then doing a tie from plate to plate for the outward thrust. You can see a plate tie in the photo on page 79 of my book. Use long tenons on that tie (5" or through) and offset it from the center post so as not to weaken the plate too much at that point; or use two ties offset a foot or so either side of the center post.