I have a need for a 2x8x27' ridge beam on a garage gable roof. I want to do it by splicing two 2x8x14's together. I've seen a few sagging splices over the years and I really want to do it right. What Simpson hardware is used to do that? The garage is 21 x 27 and uses 2x6 rafters 16" o.c. (4/12 pich),
2x8 ceiling joists 16" o.c., and this 2x8 ridge.Thanks
The ridge doesn't keep out the sags. Whei I started, we used 1 by
6 ridges. Your placement of the rafter at the plate is all that keeps it straight. Don't believe me? Ever see a ridge in a truss roof?
Only a structural ridge (think cathedral ceiling) experiences any appreciable load. Splicing a ridge needn't be furniture work.
You can butt the rafter pieces together so it falls between a pair of opposing rafters, or have the join end up between pairs of rafters (my preference). I use wood blocking to hold the two pieces in alignment as the rafters go up. There really isn't any hardware required, but if you wanted to you could use a mending plate.
R
If the roof has any kind of overhang, I'd use the ridge board out there too.
Layout the ridge board for rafter placement in pencil and framing square. Make the splice in the middle of two rafters. Use one 2X8 scab on both sides of the splice. Cut a bevel on top of the scabs to match the 4 on 12 pitch. Use an offset stringline to maintain up and down straightness for the ridge, and straightness in regards to perpendicular to the rafters. Should not be needed however if both outside walls are braced, and are straight and level, and rafters are identical. The ridge board should have a little crown to it, but not excessive, with crown up of course.
If working alone or minimal help, probably would have been easier to have a joist beam in the middle of the garage. The beam could temporarily, and/or permanently hold up the ridge until the rafters are in place. 2X6s would be adequate for the ceiling joists in that case.
This is interesting. I have never seen a ridge spliced. We always broke it behind a rafter. Some posters seem to have spliced them. Why? What part of the country does that occur in?
Has been my experience when two ridge boards tie in at a rafter, the nails tend to overextend the rafter end. And the end of the ridge boards too. That is, too many nails in too small an area. Have seen nothing in code regarding where a ridge end should "die", on the rafter or scabbed inbetween rafters. So, I've always gone with my perspective of "common sense". It sure does look purty when splicing at a rafter though. And, that seems to be the prevailing method for some unapparent other than esthetic reason. I sure don't know what that reason is.
You could get by with a 1x ridge board (it's pretty much a non-structural member), but can you get 20' lumber in 2x8 in your area? From Table R802.4(1) of the IRC, the ceiling joists are not going to go the 19'-3" in SPF unless you go with Select Structural. (That's for an attic without storage.) If your in the western states, Doug Fir is ok in #1 grade.
I'm in the Northeast. I'm not sure if it's a regional thing or not, but I know most of the framers around here do it your way. I don't like that method as there's too much going on in too small of an area. There can easily be a dozen nails or more, and maybe some metal connectors. Nailing that close to the end of a board with that many nails is guaranteed to cause some splitting. I don't like splitting. It's probably not a big deal structurally, but it's a weak point in the rafter/ridge connection. Butting the ridge pieces together and using some blocking to hold them together while the rafters are set doesn't have those problems and doesn't take any more time.
RI guess someone should ask why the OP doesn't consider using a 7 1/2 x
28 LVL. if you're angsting about splices, you wouldn't need them.I'm wondering where in the country they are still using such an old timey system anyway? I have never built a modern house (except for a small outbuilding or two) that didn't either use trusses or a structural ridge. I didn't think engineers would touch such a thing with a 10 foot pole anyway. Definitely not a labor saver!
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