Great Room framing on single family residence

[jar546]

Great Room framing on single family residence

Actually I just posted the pic for discussion with no particular issue in mind. It's just a pic but the discussions that are created has always intrigued me. This is not a test , it is simply to create discussion for us to learn from. There just may be something wrong in the pic.

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[ICE]

Actually There just may be something wrong in the pic.Sent from my iPhone using Tapatalk

Well tell us more. Did we get anything right? What did we miss?

Sent from my iPhone using my thumb

I'm getting pretty good with the thumb....little girls can do this and drive at the same time...

 

[Rio]

The shear transfer from the roof diaphragm relies on a frieze block and not the connection between the rafter and the ceiling joist. As it is, the rafter must be bearing on the flat 2x. What happened with the frieze block is not visible and there are no A-35s in the picture. So the force transfer is unknown.This being a hip roof may negate the need for a rafter tie but the whole building may need it here and there.

We should find somebody that's been there and ask them.

The shear transfer from the roof diaphragm, as you point out, is transferred through the frieze blocks. It also transfers as well by the way that the rafters are attached to the top plates as the rafters are collecting all of the roof diaphragm nailing; the more they are locked in the better the transfer. In normal framing the ceiling joists tie into the rafters and that assembly is toe nailed into the top plate in addition to the nailing of the block'g through the rafter/joist assembly, all of which is aided by the A35's at whatever schedule is called out.

 

[MtnArch]

This also looks as if it's employing what the APA calls "Advanced Framing" - where you align the rafters over the studs over the floor joists over the ...

 

[DRP]

I've always thought that if you turned a busload of carpenters loose in the Taj Mahal they'd have it thoroughly picked apart in an hour or two. With pics on the net we have the opportunity to pick apart from apart and assume what we will. Opens up more possibilities for discussion.

It looks more like just concientious guys stacking framing on 16's. We still align members whenever possible in typical framing, the corners and double plates are "un-advanced".

The bottom of the wall is probably well connected to the floor diaphragm. The top of the wall doesn't appear to be very well attached to the roof diaphragm and as Rio pointed out the thrust from the rafters probably isn't well restrained by that method of framing. I'm assuming a birdsmouth notch in the rafter is sitting on the raising plate with a boxed soffit beyond. The cj's appear to end at the building line and look to be capped by a rip of ply. If there was a rimmed floor on top of the cj's then the raising plate, I've framed that detail more than once to raise the soffit outside. It does pose connection challanges, rafter thrust and uplift. With a wall back at midspan and something going on above, there isn't much lateral restraint on the cj's. I was just looking at the bottom and top connections of the tall wall and wandered off along the top.

 

[DRP]

...pick apart from afar... I hate it when a good sentence goes bad.

 

[ICE]

Rio,

There's a few ways to skin this cat. To hear the ICC tell it, the roof sheathing doesn't get nailed to the frieze blocks.

For some reason I can't copy and paste the detail but it is:

FIGURE R602.10.6.2(1)

BRACED WALL PANEL CONNECTION

TO PERPENDICULAR RAFTERS

 

[Rio]

Thanks for the information to look at ICE. I checked it out and I couldn't copy and paste it either. What that detail looks like to me is a way to provide ventilation? I know that when we detail out roof to wall connections from the engineer we always have boundary nailing from the roof sheathing to the frieze block and back in the framing days when the inspector came out to check on the framing, if we'd covered the roof sheathing with building paper that is where the inspector would always have us open it up in that area to confirm the boundary nailing. We're in SDC D2 so maybe that has something to do with it...........