Ridge Pole Support Log - Inside / Outside

[John W]

RPSL - Inside/Ouside. Is it just preference or is there a reason? Looked through the pictures a lot and have been wondering why. Seems like it's just one more log outside to expose to the weather.

[Basil]

There are reasons to do it either way, but since it's such a vital part of the structure most of us put it inside. Simply for better protection. Some put them outside to keep them from taking up interior floorspace, but this lengthens the spans on the ridgepole so must be done with caution. If you have large overhangs and enough ridgepole to span the distance, and like the look, put it outside. Otherwise, inside. That's a simplification of course, but you get the idea.

[John W]

Excellent answer, thanks Basil.

[StressMan79]

one thing, say you are building a 30x30, on center, you have an RP with allowable spans of 17 and 6 for simply supported and cantelevered, respectively.

You'll need a center RPSL, and if you put the outer RPSL's inside, you end up with (28+12-30)/2 or 5 ft overhangs. also to make things more interesting, you'll want to have an integral number of roofing panels. Mine are 36" wide, so I'll want either 42 or 39., if you have 39, you'll only have 39-30-1 or 8 ft of total eve overhang, which goes to 4 ft/side. This is not recommended by LHBA for good reasons (a dry log is a happy log), if you put that same RPSL on the outer walls, you will still be good on your internal span, but you start @ 32 ft OC B/t them. adding 12 gives you 44. You can overhang the RP by 6 inches per side and go with 45 ft wide roof and then you have 45-30-1 or 14' of total eve overhang, or 7' per side.

This is also a consideration. You'd have to run your own numbers, but there you go. (the caplogs may become critically sized, since you don't get the additional 1 ft of span from placing the RPSLs outside.

This said, I placed mine on the inside of the structure, since I went smaller and the internal span (no center RPSL) was the critical dimension.

-Peter