split rafter at ridge beam

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Old 03-03-16, 08:10 AM
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split rafter at ridge beam

First off, I dont have a photo, but

I have 1 .. 2x6 rafter that is split and delaminated for about a 1' portion where it attaches to the ridge beam. I can see some daylight thru the split.

The wood is twisted a bit there as well. And the damaged portion is what is attached to the ridge. (if it completely detached itself from the ridge beam it would fall correct?)

I was thinking of sistering 2- 3' 2x6's to either side with glue and deck screws.

I am concerned since the wood is twisted that clamping it will not work?

Its the attachment point to that ridge beam that is damaged, I assume I need to also attach the sister boards to the ridge beam too. Is that correct?


Any advice is welcome...
 
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Old 03-03-16, 08:32 AM
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Sister the entire length of the rafter. I recently had to repair a broken ridge beam in a detached garage & I found some Simpson Strong Tie brackets at Home Cheapo.
 
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Old 03-03-16, 08:56 AM
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Here are some photos.Name:  IMG_20160303_094423.jpg
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Name:  IMG_20160303_094500.jpg
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This is the only rafter like this in the attic, must have been a bad piece of wood.

So if I sister on each side.... do I attach the sister boards to the ridge beam? If I use a bracket, am I weakening the ridge beam by screwing into it?

Also sistering the entire length is not possible, would not be able to work in the area at the soffit/wall. The damage you see in photo extends back about a foot. I was going to 3 or 4' on each side but I am confused on what to do at the point of attachement at the ridge.

Is this something I need to address? (60 year old house).
 
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Old 03-03-16, 09:50 AM
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To be honest, it isn't going anywhere if it has been up there for 60 years. If repairing it will make you feel better then ok, but anytime within the next 10 years will be soon enough.

Bud
 
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Old 03-03-16, 09:55 AM
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If you can't sister the entire rafter, just install some Simpson Strong Tie brackets.
 
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Old 03-03-16, 12:58 PM
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I guess I don't understand how rafters work.

In this case, the connection at the ridge board is obviously shot.

What's holding the rafter up? Is the lone nails in the sheared end of that rafter (barely) holding the entire board back from crashing to the attic floor?

Looking online I can find stuff about rafters pulling away from the ridge board, lots of photos with a gap between the ridge board and the rafters. Whether from shrinkage or pulling but also some that were intentionally built that way from day one. Some folks say that's not such a big deal.

Please explain?

and if I do try to sister the rafter, again I am concerned, should I be connecting them to the ridge board as well (with a bracket) or do they just get butted against it?
 
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Old 03-03-16, 01:11 PM
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Joe, all of the boards you see above that rafter are nailed to the rafter. If someone went up on the roof and jumped up and down you would see those boards flex, but that rafter isn't coming down.

Given the age of the building, those boards are probably a full 1" thick making that roof deck stronger than what we build today. I don't want to imply that you shouldn't fix what you see, but it isn't urgent.

A single 8' length of 2x6 cut to fit against the ridge beam and then screwed to the existing rafter plus the ridge beam should be fine. If you want to straighten out that twist, use two, one on each side and with longer bolts pull it all together. Then add screws up into the ridge board.

Nails are better than screws but I like that the screws can pull things in the direction I want them to go. Then nails can be added later.

Bud
 
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Old 03-03-16, 01:57 PM
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What's holding the rafter up? Is the lone nails in the sheared end of that rafter (barely) holding the entire board back from crashing to the attic floor?
The lone end nails are doing nothing and haven't for years. Bud explained very well what's holding everything together, the framing acts as a unit instead of relying on one member (mostly).
This is the beauty of stick framing. If one member fails, there's another one 16 or 24" away.

Repairing is a good idea but do it at your leisure. I would cut out the entire badly warped section and replace that section, sister as advised and connect to ridge with structural hangers.
 
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Old 03-03-16, 03:07 PM
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Thanks, I was thinking this was like an emergency thing. I certainly feel better knowing the rafter isn't being held up solely by the nails in the damaged end. I also read that a ridge board is not structural as opposed to a ridge beam.

So cutting out the twisted end.... I assume then its safe to cut out the damaged portion and just sister it. Do I replace what I cut out and then sister the replacement? And if so, how do you attach the replacement piece for the cut portion.

(the cutting out of the twisted portion seems right as the warped section is very rigid, I think I will have issue putting it back into place with clamps if left).

and as far as the bracket.... what would the best bracket be to attach the sisters to the ridge board? Some sort of L-Bracket or mending plate?
 
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Old 03-03-16, 04:07 PM
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I assume then its safe to cut out the damaged portion and just sister it.
Cutting only weakens the structure. Here's a pic of what I did in a similar situation

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Old 03-03-16, 04:50 PM
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A single adjustable hanger, like a Simpson LSU26Z would be a good idea. Sistering and gluing both sides after the hanger is on will help hold it together. I agree, it's not that big of a deal since the roof works as a unit. Well said.
 
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