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Rafter notching


DonTx
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I see this type of thing quite often. It normally occurs at a pitch change where a sloped Family Room ceiling meets the attic.

I think notching the rafter ends this way is wrong. In my world, the beam should be set low enough to accomodate the 2x12 rafters then the 2x6's can be braced to the beam.

I usually use IRC R802.7.1 (in part)

Notches at the ends of the member shall not exceed one-fourth the depth of the member. The tension side members 4 inches (102 mm) or greater in nominal thickness shall not be notched except at the ends of the members.

What say you?

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That's kinda what I've recommended in the past Chad.

I should have mentioned this was new construction. I don't get this bent out of shape when it's an older home. Just recommend a ledger strip or hangers (depending on the slope) and let them decide whether or not they want to do it.

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Originally posted by Donald Lawson

. . . I think notching the rafter ends this way is wrong. In my world, the beam should be set low enough to accomodate the 2x12 rafters then the 2x6's can be braced to the beam.

I usually use IRC R802.7.1 (in part)

Notches at the ends of the member shall not exceed one-fourth the depth of the member. The tension side members 4 inches (102 mm) or greater in nominal thickness shall not be notched except at the ends of the members.

What say you?

I don't see a problem.

The 2x6s are bearing *on* the notch. It's exactly the same situation as a bird's mouth cut at the end of a rafter where it bears on a top plate. The notch isn't going to cause splitting because it isn't stressed.

The 2x12s are also bearing against the cut face of the notch. It's analogous to a rafter that bears against a ridge beam.

- Jim Katen, Oregon

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Originally posted by Jim Katen

The 2x6s are bearing *on* the notch. It's exactly the same situation as a bird's mouth cut at the end of a rafter where it bears on a top plate. The notch isn't going to cause splitting because it isn't stressed.

The 2x12s are also bearing against the cut face of the notch. It's analogous to a rafter that bears against a ridge beam.

- Jim Katen, Oregon

Jim, you're right.

I'd still like to see the whole shebang though. If there are ceiling joists that tie the top of the lower wall to the house, there's nothing wrong at all with the notch and they just left the tail for nailing. (?)

If it's a cathedral ceiling I'd like to see a ledger or hangers under the 2x12's so that load on the beam is always vertical. The 2x12's want to push the beam and there are no opposing rafters to resist that force.

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Deep down I figured it didn't add up to a hill of beams but I still like to see something more substantial like hangers or a ledger strip.

If you look at the first pick, third rafter to the right (or first rafter on the right if you want to look at it that way) you'll see the tail of the 2x12 has split off. I commondly find cracks/splits at these tails.

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