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Old 01-02-2011, 10:24 PM   #16
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Cutting joists for attic ladder


The rafters are sitting on the ceiling joists rather than sitting next to them. Your rafters are not nailed directly to the ceiling joists, forming a “truss”, rather the rafter is above the joist, page #11; http://www.nibs.org/client/assets/fi...pter6final.pdf At least you have a rim joist preventing rotation.
Read about the spreading forces and the required continuous ceiling joists/rafter ties face nailed to prevent this on page 93. Notice the chart on page 94, if you had a 24’ span (5/12 cut) with 50# snow load, it would require 8- 16d sinker nails (face nailed) at each rafter/joist joint to withstand the forces there. http://www.ce.udel.edu/courses/CIEG4...%20-%20IBC.pdf
Only the rafter toe-nail fasteners to the flat 2x4 (and it’s nails) are keeping your rafters from coming down or pushing off the plate without the help of the side-nailed ceiling joist nails ( 8 x 93# = 744# of shear) The roof sheathing would help some, though I am not a structural engineer. If the B.D. passed it, good to go…..

The purlins and struts installed are not effective bearing on individual joists. (The purlins are laid flat rather than on edge and required to be the same thickness as the rafters). There should be a wall below for bearing. The snow load will be concentrated on the individual joists the struts are placed on. Even if the struts were bearing on a strongback over the joists, it would be ineffective and lead to ceiling finish (drywall tape) cracks or binding doors- read pp.39; http://books.google.com/books?id=iwS...rafter&f=false
You may not need the struts (I doubt you need them), depending on the span, ask your B.D. Or check your rafter ink stamp for the species and grade, find your ground snow load (Google), compare to the proper Table; http://publicecodes.citation.com/ico...002_par023.htm
If the B.D. passed it, good to go….

The ridge supports and possibly the collar ties are not required, either. The ply-clips are for OSB spanning 24” on center. (Not required, but stronger).

The OSB on the front wall for shear flow is less than I have seen, but if it passed, great. I’m in a seismic zone, Codes are more strict here….We would require 2x blocking between rafters, nailed every 6” through the roof sheathing for diaphragm shear. Especially the left side of the garage, for a two story- 24” wide minimum or hold-downs required; Figure 6 (c); http://www.xpsa.com/tech/FSC%20Braci....2%20FINAL.pdf If it passed, good to go.

I may have you worried for nothing, maybe one of our resident Engineers will chime in………..
I may not be seeing everything clearly, also, lol.

Gary

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Old 01-03-2011, 06:48 AM   #17
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Cutting joists for attic ladder


Quote:
Originally Posted by gregzoll View Post
Even better like building a house, and not putting any plumbing or electrical in after finish work is done.

Thanks for the memory....

I got a call from a client saying his house was broken into during construction and they stole all of his Copper Piping. I explained that is not a problem but, he needs to understand that we were finished our job and had the inspection so if he wanted us to redo the work we would need to bill him again. He yells for about 30 minutes and then calls his insurance company who set up an appointment in 2 weeks. The Home owner never told the drywall guys and they had all the Rock hung in that house in less than a week! No Plumbing in the House but the Rock was Hung! Insurance paid for the Plumbing but not the drywall
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Old 01-03-2011, 07:04 AM   #18
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Cutting joists for attic ladder


GBR the top paragraph sound dire. Short of tearing off the roof and rebuilding how would I increase strength on what's already there?
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Old 01-03-2011, 07:12 AM   #19
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Cutting joists for attic ladder


By Purlin & Strut are you referring to the flat blocks above the wall in this pic:



I may have misunderstood, I thought these were supposed to lie flat for side to side partition wall strength. Can I add additional blocks and lay them vertically beside the existing blocks? The wall didn't exist before, so it is not load bearing.
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Old 01-03-2011, 09:02 AM   #20
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Originally Posted by GBR in WA View Post
The rafters are sitting on the ceiling joists rather than sitting next to them.
That's the way my house was built 50 years ago. That's also the way MANY houses around here are built. As an electrician, I notice this extra height when snaking a wire down the exterior wall, it's definitely nice to have that room for your body and for the drill.
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Old 01-03-2011, 12:36 PM   #21
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Cutting joists for attic ladder


Page #8, your choice.....every 4' apart. Notice also the purlins in that article.
http://www.apexhomeinspections.biz/a...guidelines.pdf

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Old 01-09-2011, 11:28 AM   #22
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I hope this is strong enough.. I won't be carrying more than 20-30lbs up the stairs (rated at 350#) but wanted to over build it just in case.





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Old 01-09-2011, 12:35 PM   #23
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Cutting joists for attic ladder


Nice job, thanks for the follow-up pics
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Old 02-23-2011, 10:23 PM   #24
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Cutting joists for attic ladder


Here are a couple pics of the header plate & rafters. I've had a couple guys come by and look at it. One said it looked basically fine but could use strengthening up, the other said it wouldn't fall apart tomorrow, but would start to pull apart over time.

Both suggested adding hurricane straps attaching the rafter to the header plate.







Makes me furious that the builder didn't do this while building the shop. I would have gladly paid extra had he just told me.

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