A-Frame Beams

[Harry McBride]

Hey guys! I inspected a A-Frame home yesterday with wood beams that went from the floor level to the tip of the A-Frame. The issue is that there is no bracing between the beams and the beams have slightly separated from each other. The home is 34 years old and I have no idea whether the separation occured as the unbraced beams were drying or from structural stress. The movement appears to be old. I was surprised not to see any bracing or metal strapping. Any ideas would be great.

[jking2]

It looks like the beams still line up at the peak, but at the bottom there is about a 1" exposure. This may be due to the beams taking on a left hand twist while drying.

Jim King

[rcramer]

Kinda looks like a crappy cut to me, do you have any other pictures?

[David P. Valley]

I see this roof framing all the time. Those small gaps and minor twists are no big deal. It's minor settling of the building over the years.

These older homes didn't have ridge boards and collar ties. If the roof structure appears fine and there's no obvious signs of structural issues with the rafters, then simply report what you see.

No big deal from what I see in your pic.

[Richard A. Hetzel]

It's possible the beams/rafters are fastened together from the outside, probably by through-bolts, which would now be concealed by the decking.

[pdickerson]

Framing lumber is sold kiln dried so it won't shrink and twist, but beams are sold green. It looks to me like the beams dried out and shrunk in the process. Wood shrinks accross the grain, but not with it. An angle cut at the end of a beam will become more acute as it dries out and shrinks. This accounts for the joint that is tight at the top and gappy at the bottom. I don't see this as a problem.

[afrost]

Originally Posted by pdickerson

Framing lumber is sold kiln dried so it won't shrink and twist, but beams are sold green. It looks to me like the beams dried out and shrunk in the process. Wood shrinks accross the grain, but not with it. An angle cut at the end of a beam will become more acute as it dries out and shrinks. This accounts for the joint that is tight at the top and gappy at the bottom. I don't see this as a problem.

kiln dried framing lumber does twist, sometimes like a banana.
beams are available seasoned.

there is tendency for the rafters to spread at the base of the a-frame rafters. but the slab (or whatever the floor system is) can be the base of the "triangle" that keeps the system together. perhaps that spread a bit and thus the ridge cut of the rafters have spread. or perhaps it was not a good cut -- not the easiest cut for the average carpenter.

i don't see it as an issue.