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An average day

Ty,
The roof diaphragm edge nailing is achieved by the 2x blocking (shown). 8d @ 6"o.c. is required per Table 602.3(1).
That is not the edge of the diaphragm. This is a huge misconception that I have seen spread wide and far. The edge, is the actual edge of the sheathing - the rim board at the edge of the eave. If in a SDC 'C', the truss/rafter blocking is not even required.

Check out the following - https://www.sbcindustry.com/system/...am/node/pdf/1185/educationpptheelblocking.pdf
 
That is not the edge of the diaphragm. This is a huge misconception that I have seen spread wide and far. The edge, is the actual edge of the sheathing - the rim board at the edge of the eave. If in a SDC 'C', the truss/rafter blocking is not even required.

Check out the following - https://www.sbcindustry.com/system/...am/node/pdf/1185/educationpptheelblocking.pdf

The edge of the diaphragm is where the boundary nailing occurs. In our case that's over the eave blocks so that a transfer to the wall can be accomplished. The 602 diagram that you posted is in fact in our residential code.

The following detail is what we apply:

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The edge of the diaphragm is where the boundary nailing occurs. In our case that's over the eave blocks so that a transfer to the wall can be accomplished. The 602 diagram that you posted is inn fact in our residential code.

The following detail is what we apply:

View attachment 5788
Ok, so your jurisdiction has a local amendment that requires something other than the IRC.

That's great, but the IRC does not require what you were illustrating.
 
Ok, so your jurisdiction has a local amendment that requires something other than the IRC.

That's great, but the IRC does not require what you were illustrating.

I didn't realize that I was out there in left field. I do try to refrain from leading the masses astray. For all that see this please understand that what I post or do has little relevance beyond where I work.....and you don't. As Chevy Chase would say, "I'm tigerloose and you're not"
 
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I recently built a home that I specifically asked the engineer to design it without bird blocking so I could get full airflow from the soffit vents up through the cathedral ceiling,
 
This was just getting good
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I recently built a home that I specifically asked the engineer to design it without bird blocking so I could get full airflow from the soffit vents up through the cathedral ceiling,

The roof diaphragm can provide a little or a lot of resistance. It depends on the building that’s under it. My engineer explained that a recent roof was built with the capacity for 260 lbs. per lineal foot but only 60 lbs. was required.

The subject came up because an inspector disallowed roof sheathing that was fastened with staples instead of nails. As it turns out staples are about 80% as efficient as nails. Then another engineer said that staples allow movement greater than that which a nail would allow.

It is worth noting that plans almost always specify common nails and common nails are almost alwys replaced with sinkers. A 20% reduction for sinkers is about right.

As an aside; try ripping stapled plywood from framing..... It ain't coming off.
When I worked as a carpenter I used a finish nail gun for things like handrail backing and fireblocks. The nail gun is smaller which is a plus and the block wouldn't move when I shot it. Other carpenters scoffed until they tried to pull a block out.
 
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FIGURE R602.10.8.2(2)
BRACED WALL PANEL CONNECTION OPTION TO PERPENDICULAR RAFTERS OR ROOF TRUSSES

Is an alternate which uses the eave and then transfer the load using soffit sheathing back to the braced wall panel.
 
The second story addition is legal.

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This was approved too.

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Needs paint.

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A well advertised contractor asked me to approve a furnace and A/C. They just don't even try to get it right.

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California has a requirement for a "cool roof". The color of the roofing is one indicator of a cool roof. The installation of a radiant barrier is one exception to the requirement. That applies to much of the state but not in my jurisdiction as we changed it up some. So the company that manufactures Low-E touts it as a radiant blocker.....not a radiant barrier.....ICC is quick to point out that Therma Sheet has not been tested or approved as a radiant barrier.

It looks like a radiant barrier what with the aluminum foil and all......but it's not. A legitimate radiant barrier requires a minimum one inch air gap. I see OSB with radiant barrier being installed over 1"x sheathing because the people doing it lack an understanding of how it works.

While the energy requirements are sorta important the bigger concern is the up to 7/16" layer of foam rubber under an asphalt shingle. Even if they go with one layer of Therma Sheet and one layer of felt, there's the lap splices.

It's one of those things that a right thinking person recognizes as foolish but there's nothing that can be done about it.

Won't foam rubber break down from heat over time?
 
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