Repairing a beam in a mortise/tenon barn

Re: Repairing a beam in a mortise/tenon barn

Carol from AZ

>You might Google Timberframers Guild of America.

Re: Repairing a beam in a mortise/tenon barn

Thomas Skaggs, Foothills of Mount Level

>This is a notion:

Could you....

-Remove the damaged timber

- Create a new timber to fit

- Cut mortises in both ends of the new timber

- Cut through mortises in the sill and the 1rst floor beam to correspond with the other mortises.

- Make independent tenons (square pegs) for both ends.

- Excavate a little under the sill enough to insert upward and tap in the new loose tenon.

- Insert the top tenon from above and tap into place.

- Peg both tenons from the side to keep in place.

Ok, I may not be visualizing the situation properly but it's just an idea.

Tom

Re: Repairing a beam in a mortise/tenon barn

Ernie Miller

>I agree with carol about checking with the timber framers. I can tell you that you will not be able to remove the old one and put a new one peice beam back in with out doing some major demolation. You will be able to make a two peice beam that can replace the old one but it will not be as strong even if you pin and glue the splice together. It will probably be strong enough as most of these barns were pretty much over built. I could make a drawing for you but all the demensions will have to be adjusted by you.

Re: Repairing a beam in a mortise/tenon barn

Stephen Kirk in Quakertown PA

>Hey, that's a good idea. I've looked up their site before, they must have just escaped my mind at the moment.

That's what I was thinking.

Jason Roehl in Mulberry, IN

>I'd say get a jack under the upper beam, just enough to take weight off the support beam, then cut out that support. Like Tom said, make the mortices into through mortices and use floating tenons. You might even be able to make the bottom tenon solid, slip it in, then only use a loose tenon on top, doweled from the side to pin it in place. A little construction adhesive wouldn't hurt, either.

Jason

Re: Repairing a beam in a mortise/tenon barn *LINK*

John McGaw

>I am not a timberframer and I do not play one on TV but I am sure that there is a rather neat variation of the scarf joint used in the trade to splice timbers end-to-end. This variation is self-locking under pressure and seems as if it would be ideal for this sort of task. Basically one would create a replacement timber on the ground just a hair (well two saw kerfs anyway) longer than is needed, cut the joint to split the timber in half, install the halves into the gap and then slide the joint together and pound in a square peg to lock it.

As an afterthought I looked up a picture of the joint in use.


Scarf Joint Photo

Re: Repairing a beam in a mortise/tenon barn

Ed Mulligan, Cape Cod

>How about a steel plate to bridge the damaged area? Or a threaded rod like those used to laterally support the sides in old brick homes?

If the repair must be made of wood, make a lamination in place with epoxy. The center piece has suitable tenons and is length and width of original beam. Crosscut this in half. Insert halves in mortises. Laminate timbers to the two sides of the center piece to make up the original beam dimensions.

Ed

Re: Repairing a beam in a mortise/tenon barn

Barry Irby

>I have no Idea what the "proper" repair is. Check with the Timber Framers Guild.

OTOH you need to know whether the timber in question is in tension or compression or both or in bending.

Also, you metioned the timber was "chewed" partially through. Does that mean the horses have been chewing on it? I understand they do this sometimes. If so, you need to check that out. I am given to understand it might be some sort of "issue" that might be possible to limit by changes in their feed. (I'm not at all sure this is true, but its worth checking.) What you need to know is whether the horses will chew through the repairs also. If so you need to be sure they won't be harmed. No treated or toxic woods.

Do the repairs need to be authentic or just structural. If they only need to be structural you could make them with a couple of angle irons bolted to the existing beam. That would make it almost imposible for the chewing to do any more damage.

Re: Repairing a beam in a mortise/tenon barn

Gene Gauss

>I replaced one of the diagonal brace beams in my barn by making it in pieces. The first piece was the thickness of the tenons on each end, the width of the beam the same as the one being replaced, and the full length that it would have to be if I could have put it in in one piece. Next, I cut that piece in half and fitted the tenons on each end. Then I inserted each piece into the mortices on each end, and plated planks of appropriate width and thickness that fitted up against the inside dimensions between the posts on each end using lots of decking screws to make a good strong laminated beam (in your case, it would go between the sill and beam). I drilled through and replaced the wood nails made of dowels trimmed to fit tightly. I could have glued between the laminations, but didn't think it was necessary. Not difficult - not even tedious. Gene Gauss