# Toe nails = bearing?



## Darren Emery (Mar 2, 2012)

Pardon the poor drawing - my drafting classes were decades ago. Lower end of rafter, intersecting a valley rafter.  MY SOP has been to require mechancial fastener, or PE review.  Am I off base here?

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## fatboy (Mar 2, 2012)

Nice drawing actually. My position, there have been valley rafters around for centuries, without the benefit of engineers approval or engineered hangers. I've not had issue with them.


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## mjesse (Mar 2, 2012)

Nails are acceptable for the cheek cuts on hip and/or valley jacks.

No PE review


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## codeworks (Mar 2, 2012)

table 602.3(1) 2006, we are not in 2009 yet, go with the fastener schedule in the code book, roof rafter to ridge or hip/valley rafter, toe nails=4 - 16d, face nail, 3-16d. is there some ungodly roof load (snow) that would require a hanger or a pe design on this ? i wouldn't think so unless it's alot of snow, or some other condition, i'd just use the schedule in the code book


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## KZQuixote (Mar 2, 2012)

Darren Emery said:
			
		

> Pardon the poor drawing - my drafting classes were decades ago. Lower end of rafter, intersecting a valley rafter.  MY SOP has been to require mechancial fastener, or PE review.
> 
> Am I off base here?


I agree, nice drawing.

From 2009 IRC

602.3(1)

Item 6 Roof rafters to ridge, valley or hip rafter:

Toe nails 4-16d

Face nail 3-16d

No hangers required.


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## High Desert (Mar 2, 2012)

I agree with the others. There are prescriptive nailing provisions that address it. Don't know how you could require more than the code requires.


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## Darren Emery (Mar 2, 2012)

This is why I love this forum.  I read, I post, I debate, I learn.

Already been to the site, ate a small serving of crow, and stoped the framer before he put any work into the fix.

Thanks all!

Darren


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## codeworks (Mar 2, 2012)

when in doubt, i like to use, "give me some time to check on this and i'll get back to you". that way i'm not painting myself into a corner. besides, it's not easy to keep 4 code books, city ordinances, policies and procedures memorized for quick and easy access. even if it is expected of us as building inspectors. thats why it's in print. bugs me when i can't find it when theres a contractor i just wrote up ofr a violation who says "show me". ok just give me time.......


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## KZQuixote (Mar 2, 2012)

Darren Emery said:
			
		

> This is why I love this forum.  I read, I post, I debate, I learn.  Already been to the site, ate a small serving of crow, and stoped the framer before he put any work into the fix.
> 
> Thanks all!
> 
> Darren


You're a good guy Darren!

You've demonstrated your commitment and should be recognized for it.

Bill


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## fatboy (Mar 2, 2012)

Crow is best when warm......having had to eat at that table.


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## Daddy-0- (Mar 2, 2012)

I agree. Admitting mistakes is a huge step. Many inspectors never get there. It is good for the profession to have people who want to learn and admit mistakes. Nice job


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## ICE (Mar 2, 2012)

I'm wrong often enough.  I'm right now and then too.  Today a contractor started to complain about the number of corrections he got.  I told him to be thankful that I can't remember all of the code.


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## TheCommish (Mar 2, 2012)

If I could just get the contract to put half as much effort to the drawing as you they would be better off, nice job.

I will never enforce something I cannot cite chapter and verse, I will say I don’t think it is right if am not sure, I am willing to have intelligent discussion, draw a lot on walls and always am mindful what has work for years needs education to change.

We need to afford the tradesman the chance to city the exception or the code verse that allows what they want to do if it exists.

And besides there are about 8500 pages of code plus 150 pages of zoning ordinances that I enforce, I am not Dr. Spencer Reid (Criminal Minds) therefore I cannot remember everything.


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## jim baird (Mar 3, 2012)

I see the rationale you mis-applied, Darren.  I can't quote a reference, but I see the bearing requirement as applying where the load is in a vertical direction.  Those angled cuts of rafter ends need bearing for the full length of the angle cut where they meet the ridge/valley/hip member.

That's where I see problems a lot, when the "heel" of the cut is resting on air instead of wood.  I especially see it on step stringers where that angle cut has no meat under the heel.


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## DRP (Mar 3, 2012)

I do appreciate your attitude. For me that is the call that tells me everything about the character of the inspector I'm dealing with.

I don't really trust many of the codebook connection tables, the connectors and conditions assumed are almost always wrong for my situation. I'd study the joint for a minute and do some simple math rather than trying to force a fit in a table. For this take: (The longest jack's horizontal span X its spacing X total load) /2 = ~load on each end of the jack rafter. Divide that by the allowable lateral load per fastener per the NDS, the connections calc at awc.org is the NDS math. You could figure each jack's required nail count for that matter.


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## steveray (Mar 5, 2012)

Hip and valley rafters shall be supported at the ridge by a brace to a bearing partition or be designed to carry and distribute the specific load at that point.

   See that one abused here alot also.......That connection always bugged me too Darren, if the contractor gives cause for concern, you can ask to see his "common" nails the code calls for...proabably used a gun....I don't think there is a code section for rafters like 502.6 for floors that calls out specific bearing...if there was, I would think it could be called out...In lieu of that nails are OK, then nail location also has to be considered....


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## Darren Emery (Mar 5, 2012)

Thanks all for the responses, and the kind words.  Much appreciated!

I learned long ago - perhaps week one as in inspector - that if I'm not willing to admit I'm wrong when I am - that I was going to have a long, difficult, and contentious career.  Life is too precious and short for that.

A couple of thoughts on my rational for this call, for purposes of further discussion, not justification  

1 - The commentary got me headed in this direction.  Yeah, I know, not enforceable, but useful for education.  From R802.6 - "The requiremens for roof rafters and ceiling joists bearing on wood, metal, and masonry are similiar to the requirements for floor joists.  See the commentary for Section R502.6 relative to the bearing requirements for wood metal and masonry."

2 - On this particular roof, the rafters are at a fairly acute angle coming into the valley rafter, and therefore the cheek cut has the rafter tail very thin.  The toenails go through very little meat of the lumber.  How much wood does the nail need to penetrate to really carry the load?

Thanks again, and hope you all have a great week!

Darren


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## steveray (Mar 5, 2012)

Your #2 item is what I was referring to at the end of my post....IRC does not give ANY info (other than quantity) on nail placement....you have to go to NDS or MFCM....


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## ICE (Mar 5, 2012)

Darren Emery said:
			
		

> 2 - On this particular roof, the rafters are at a fairly acute angle coming into the valley rafter, and therefore the cheek cut has the rafter tail very thin.  The toenails go through very little meat of the lumber.  How much wood does the nail need to penetrate to really carry the load?
> 
> Darren


No matter how acute the angle, it reaches full thickness.  Nailing near that point would make sense.  Splitting is an issue; especially with 16d sinkers and commons make it worse.  If sinkers are used, a 20% reduction in capacity from that of a common is typical.


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## Mule (Mar 5, 2012)

Darren Emery said:
			
		

> 2 -  How much wood does the nail need to penetrate to really carry the load?  Thanks again, and hope you all have a great week!
> 
> Darren


I've always heard 1 1/2 times the thickness of the wood. Which makes a little sense. You figure the length of a 16D is 3.5 inches. Normally you are nailing two 2 X's together. That's 3 inches sooo.....1/2 penetrating through the 2 X's. Close to 1 1/2 times. But now the codes allow for 10D's so that blows that theory!


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## DRP (Mar 5, 2012)

Mule, an observation on the 10 diameters required penetration into the bearing member, don't know if it means anything.

Back in the day a 2x4 was 1-5/8" thick (1.625") and a 16 common is .162" diameter, you can get 10d and full value in the face of a stud. Now a stud is 1.5" thick and a sinker is .148" diameter... 10d. I'm not sure but I think it's a conspiracy.

On #2 the NDS goes down to 3/4" sawn side member in the tables, you could interpolate between that and the 1-1/2" side member lines and not count nails in the <3/4" thick feather edge.


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