Improper rafter repair, right?

Section of decking and rafter was repaired on a ~1960 house. I’m thinking that brace should’ve been centered under the joint and not nailed to the side of it, correct?

Anything to say about the sistering?

The sister should have been far longer.
The vertical brace is suspect: what’s it bearing on? Is it disturbing the truss effect of the rafters? Why is it even there?


Right, im finding a number quoted online that says 3’ past the joint on each side, and fastened with nails as well as carriage bolts every 16". does that sound right?

I dont know for sure, there was very sketchy boards in the attic and I didnt dig around. Im assuming it’s nailed to the side of the joist below it like it is to the rafter above.

It seems like an amateur/diy job. Im thinking they wanted to make sure it doesn’t cave in when they were putting a new roof covering on. Would you recommend they sister it correctly and then just remove the brace? There are purlins/braces further up the rafters from this point.

As a home inspector, you just say it’s wrong, and refer to a framer/contractor.

I’d also take a good look at the attic or your photos to see if any extra or removed purlins or braces are an issue. Rafter trusses are designed, and can’t be messed with with impunity.

If I were doing it myself I’d run the sister rafter all the way up to the purlin, as long as possible. I’d absolutely remove the vertical brace. It changes how the roof loads based on wind or seismic, and simply can’t be good.

Had I a time machine, I’d have run the sister from the purlin to the edge of the roofline. But it’s too late for that.


Great, thanks a lot Bryce!

Agreed. Load point to load point.

No. That is no where near “right.”


good, because I just put “improper rafter repair, seek professional framing contractor”, more or less… but what would be the proper sistering method? nails and bolts and 6’ sounds pretty secure to me.

In general, use a full-length rafter. Partial repairs IMO require some design work which will cost way more than buying a few full-length rafters. As a structural engineer, I am required to factor in dead, live, wind, and snow loads which may seem like overkill to the average DYI individual, but to do anything less would be unethical and could cost me my license. By the time I get called out, especially on stick-built roof problems, a simple broken rafter turns out to be an entire roof that needs bracing.


As a PE or SE, what do you think about the extra vertical brace added in the original repair.

(Note: I see stuff like that often)

Unless there was a support wall or beam under the vertical brace I see nothing good about that repair.


engineers! :laughing: :grinning_face_with_smiling_eyes: This ain’t no Taj Mahal!

Afternoon, Bryce.
Hope this post finds you well.

I would use the word/adjective, “SUSPECT” as to not box myself in having to explain or opine on the repair under deposition or communicating with professionals if it was not my strong suit.

Observation: Repaired roof deck rafter and decking.
Suspect, rafter repair.
Recommend: A licensed carpentry contractor evaluate the rafter repair.
Act upon any referrals offered.
Limitations: Inspect from the attic hatch. Insulation limited visibility.

For better or worse, I am a person of action, and want to ensure my reports (and this is NOT my report) call out the issues that really need fixing as such.

Using too mild a word leads to buyers and sellers mentally prepared to do nothing.


Any collar ties?

That vertical brace has created a new load path from the roof to the attic floor that the original designer likely did not account for in the framing.


Nor did they place the brace under the splice. It’s crap. :smile:


exactly. These are not trusses, as others have stated. It is stick framed rafters, and that vertical piece puts load on the ceiling joist that is only designed to carry the weight of the drywall. (unless a wall underneath this point)
I also recommend that any sistering be done full length

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You have to be subjective in this case. It is 1 repaired rafter. As well, we do not know where the brace was in terms of, how far down the ridge to the edge of the roof eave the rafter spit scab was, and if there are collar ties. So I highly doubt 1 repaired split rafter repair will take that much load transfer.

Think subjectively. 1 of a posable 16x2 rafters baring the roof assembly would be what as compared to where the repair is on that side of the roof? Minimal I suspect.

If the repair fasters where washered lag bolts and proportionally staggered vertically/horizontally in a pattern, like a ledger board, with the sistered lumber glued to laminate the 3 pieces of lumber together, it would be but a mention in my notes.

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That mid-span brace would add a 207 pound point load to one attic floor joist, mid span, if that home were in my county and had the same dimensions and configuration of my roof, during the peak high wind event for my county as prescribed by ASCE 7-16. That load would push the attic floor joist past the deflection limit (L/240) by a factor of almost 2.5, and result in drywall cracking.