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cut rafters


Ken Meyer

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Got a call from a homeowner this morning. He just has a new roof installed, they added ridge vents. The goof who cut the sheathing for the vents set his saw too deep and cut into every 2x4 rafter about an inch or so. Some of the rafters are now notched at the top where they meet the ridge board, which is a 2x4.

The roofer is offering to repair the rafters by attaching plywood gussets on either side of each rafter. It seems like a reasonable fix to me, what do you think? Would it be better to sister some short pieces of 2x4 onto the cut rafters?

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If I saw this during an inspection, I would let a qualified builder or engineer design a repair.

But, since this fellow is asking you directly, I suppose an opinion is called for.[:)]

Plywood will not provide very much bearing surface on the ridge board.

Lengths of 2X4 could be nailed or screwed in there, but the shingle nails will get in the way, and it will turn into a joke if this same worker trys to do it.

I don't know. Is there a Simpson tie for that application?

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No prescriptive method covers that, so technically an engineer is called for. Practically, I'd probably just go with the gussets. 1/2" CDX, 6 gun staples to a side. Talk to a truss manufacturer if you wish. If I detailed here what I'd do myself, we'd have a two page thread before the night was over.

Marc

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I don't know. Is there a Simpson tie for that application?

The only thing I could find from Simpson was the LSTA/MSTA series from the High Wind Framing Connection Guide. It's a strap that fits on top, not installed from the bottom. You'd have to removed some decking.

Marc

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If it were my house, I'd never even fix it, based on the location of the cuts.

After looking again at the pictures, the bottom edge of the rafters lack any bearing-- I'd prefer that was fixed.

I agree. If you finish the last 1/4 inch of the top cut, and look at the small ridge board, from the picture it looks like you've only got a couple of inches total support on each rafter.

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They look like 2x4 rafters and will sag or break in the middle

Or split right about where the bottom of the ridge board is located.

Ken,

Technically, a PE is supposed to design a repair for those damaged rafters. If you get involved in telling them how to fix this, you may be overstepping in my opinion.

Any chance you could e- mail the pictures to a PE in the area to see what he/ she thinks about it?

The roofer is offering to repair the rafters by attaching plywood gussets on either side of each rafter.

What size must the plywood gussets be?

Fastened with glue, nails, and if nails, placed where?

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This is one of those things that's wrong, the roofer was a doofus, but c'mon......how bad could it get?

I mean, the rafters don't even have bearing, but they've held up for 75 years without splitting.

It looks like an old dump that probably has a 100 issues worse than this. I see so many old dumps that have been hacked and jacked repeatedly, they make this look benign. Like gtblum said, jam a shim in the cut with some epoxy if it makes you feel better.

If you call a PE, they'll scratch their heads, furrow their brows, and probably say it's stupid, but harmless. I've not met many PE's that know much about old house carpentry; most of them around here look @ old houses, and then immediately insist all new structural steel be installed to replace all the timbers that have worked fine for 100 years.

As far as the homeowner's question, I'd probably say I'd have to come out and look, and then charge them for my opinion, cost dependent on how far I had to drive.

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Ken,

If they took of five layers that frame is breathing easy.

Let the roofer add the gussets just as an act of penance.

I'm with you, Jim. Furthermore, those gussets should be solid oak, in keeping with the heritage aspect. [:)]
Heritage aspect?

Seriously? The home is only 87 years old. Plywood and drywall have been around longer.

ONE TEAM - ONE FIGHT!!!

Mike

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