Hello, I am new to the Guild, thank you for adding me. I am hoping to get some information for a small loft project I am working on.
I was looking for advice or suggestions on building the header beam. My thought was to use a scarf joint to join the beams. Supporting the beams at the joint. I am new to timber framing so I am open to any ideas on a better option to join the beams. Also, I was planning on using reclaimed hand hewn oak timber and was curious on the good or the bad on using that vs new lumber. I have included a very rough sketch for dimensions.
Dave I'm new as well and I think the scarf joint seems to be the way to go. I haven't heard or seen any other technique to accomplish what you are looking to do. I've seen it done a couple of ways. Check this out:
There have been many studies by the timber framing guild engineering council on scarf joints. You should research this idea of a scarf joint over a post. It is usually recommended to NOT be over a post. When you put a timber over a post you are asking that timber to give you all it can give you to support your frame. Then you can half of it away. How can a timber give it all the strength you need if you cut half of it away? Do more research on scarf joint locations and find a better location for your scarf joint.
Thanks for the reply. And thanks also for adding the the links. Two good examples. The fit on these joints and others I have looked at is amazing. I have some old pieces of timber I will definitely be practicing on.
Thanks so much for the information and suggestions. I have been searching the forum. I found a thread that you posted to from years ago on joint placement over a post concerning the force/stress points. Looks like the joint should be located at some point next to the post. I had thoughts about losing some strength by cutting half the beam away like you stated. When I had looked at scarf joints in some old barns in my area most of those seemed to be over the post so I guess I thought that was ok.
I think I will need two joints as my span will be 35’. I don’t think I can find a beams long enough to make it with one joint. Do you know if two joints would be an issues? Maybe I will need to move the joints just past the post towards the center of the 14’ section?
You can cut as many scarfs as you need as long as they are in the correct supported locations. I once cut a 56' long plate with 16' timbers so we had to do several scarfs along that side. There are other style scarf joints that are easier to cut and assemble. Which type depends on the forces on the timber. If it is a tension timber then one type is used. If there is low or no tension in the timber/frame then another can be used. If it is a tie beam, then most likely there will be tension in the timber holding the two wall together. I would use a stop splayed tabled scarf with under squinted butts and wedges. This is a good joint for tension timbers. Good luck with your projects Jim Rogers