The Forestry Forum

General Forestry => Timber Framing/Log construction => Topic started by: TomRosa on May 04, 2022, 09:41:49 AM

Title: King post post to ridge beam.
Post by: TomRosa on May 04, 2022, 09:41:49 AM
Hi. Im working on my round wood timber frame and im coming to the point of raising the ridge pole.

Ive seen a video on a log cabin build and they use a dowel / peg system.

https://youtu.be/qczgg6xbiqM?t=3199 (https://youtu.be/qczgg6xbiqM?t=3199)

Is this a common technique, and what are your thoughts?

What are the other ways of seating the ridge beam?

Thankyou
Title: Re: King post post to ridge beam.
Post by: Don P on May 04, 2022, 06:31:47 PM
Hi Tom, Welcome
We are supposed to provide a "continuous load path" that can handle up, down, and sideways.
The peg does a good job with down and sideways but does nothing for up. The nails are a bit better but in green end grain the penalty in withdrawal is something like 75%. Threaded screws or lags will probably get you there. A tenon in the post top into a mortise in the ridge with a peg across the joint. Down at the bottom a tenon on the post into a water collecting mortise in the top log will do the job but there is the risk with upward facing mortises, detail to keep it dry. Steel knife plates could also be used in place of the pegs, then a cross pin through the plate in each member. 1/4 the weight of that roof is on a post that is supported by a spanning log. That needs to be checked or chocked. His end posts will settle with the building. The center post will not settle, there should be a screw jack under that post.