Rotating rafters

[Jim Baird]

At least six in a row rafters meet at peak with engineered trusses with no ridge board. Every one has rotated. Surprisingly it doesn't look that bad from outside.

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[mjr6550]

The support for the rafters is wrong even if they had not rotated and were properly attached. From a structural standpoint that is about the same as notching the rafters about 50% at the ends. They will probably split.

[John Kogel]

Amazing! [8D]

Now how do they fix it?

[Jim Baird]

I pointed out the lack of bearing too, Mark, and yes, one or more had begun to split.

If you could fit in a ridge board and fasten those ends somehow it might arrest the development, maybe.

[Marc]

Glue two pieces of 3/4 CDX together to make a 1 1/2 inch thick sheet. Cut pieces out that will fit the void at the top of the trusses and glue them in place to provide support to the rafters. Glue/staple some 1/2 inch plywood gussets on top on both sides.

Not too hard to do and the glue (Titebond II Premium) is stronger than the wood.

I don't know about the ones that rotated. Might have to open up the roof to change them.

Where's Kurt? Few can sing like him on a lot of topics that come up here.

Marc

[Tom Raymond]

Or one could just buy a house that doesn't have obvious structural defects.

[Jim Baird]

Thanks, Marc. I was thinking like that as well tho I haven't suggested a fix method. The gussets will make the support but I think a fat horizontal tie as well, nailed to the bottoms.

[Charlie R]

You may be able to drive solid blocking between the rafters to straighten them out, doesn't always work, but sometimes you get lucky. The blocking would then keep them from rotating if you can get the blocking in place.

[John Kogel]

Right, a factor to consider is access, getting lumber up there, swinging a hammer up there?, etc.

Then who knows what else is hidden away in that structure?[:-magnify

[Jim Baird]

Also a rafter that has turned, if pulled back straight, may push the shingle nails up through the surface. I have suggested to a carpenter who called me about it that stopping the movement where it stands is the best you can do short of tear off, out, and rebuild.

[mjr6550]

Attaching plywood or OSB gusset plates to each side of the joint is probably the best approach. That is the same repair typically used for damaged truss joints.