# Inspector want ridge blocking on truss roof.



## tornstrom (Sep 5, 2012)

I just had my house that I built inspected (final inspection) and the inspector claimed that I need to have blocking between the trusses at the ridge. Since I have a ridge vent I would need two pieces of 2x4 blocking on each side of the vent (at most 12" from the ridge). This sounds very strange to me, and I have never seen that done before and I can't find any photos online where it's done that way. Is he correct? If so, can anyone point me to where in the IBC it says I need that? I would understand if it was a stick framed roof, then the ridge board would be essential, but blocking seems to serve no purpose other than temporary bracing while setting the trusses. 
Any comments welcome!


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## SeniorSitizen (Sep 10, 2012)

Ask him to point out the IBC you need to follow.


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## tornstrom (Sep 5, 2012)

SeniorSitizen said:


> Ask him to point out the IBC you need to follow.


It's IBC 2012


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## stick\shift (Mar 23, 2015)

SeniorSitizen was not asking for the version of the IBC but the specific code reference which specifies this.


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## tornstrom (Sep 5, 2012)

stick\shift said:


> SeniorSitizen was not asking for the version of the IBC but the specific code reference which specifies this.


Ah, ok. I'm going to ask the inspector that.


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## Bud9051 (Nov 11, 2015)

Just pondering out loud for a moment as I have not run into that myself, but I can almost see some reasoning. Edge clips are often required to tie one sheet to another for support. At the top, there is no "next sheet" so that edge remains unsupported. Perhaps the blocking is being specified to support that top edge??

Bud


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## tornstrom (Sep 5, 2012)

Bud9051 said:


> Just pondering out loud for a moment as I have not run into that myself, but I can almost see some reasoning. Edge clips are often required to tie one sheet to another for support. At the top, there is no "next sheet" so that edge remains unsupported. Perhaps the blocking is being specified to support that top edge??
> 
> Bud


Yes, I can see your point. If I felt there was a need for them I would for sure have put some blocking there, but these are the very-strong 1/2" zip roof panels and they hardly bow even if you stand on the very edge (thye don't even require clips). I been looking trough IBC 2012 and from what I can tell it's up to the truss engineer where any bracing should be. I haven't heard back from the inspector yet.


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## craig11152 (Jun 20, 2015)

A few thoughts 
*Seems like that sort of reasoning would create some issues venting a cathedral ceiling. 
*I've never heard of such a thing in my area.
*why wasn't that addressed in a framing inspection?
*whats the guy really want? $20?, $50? $100?


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## PatChap (Nov 17, 2012)

If its not called for by the truss company its not neccessary. Worst case ontario, ask the inspector to point out the ridge blocking on the truss plan.


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## Tizzer (Jul 24, 2010)

. Since I have a ridge vent I would need two pieces of 2x4 blocking on each side of the vent (at most 12" from the ridge).
.......................
Wonder why he wants 3 inches on each side. Seems like overkill to me. That and that 1 foot tolerance. Either put them at the top where there isn't any support or don't use them at all.:vs_worry:


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## craig11152 (Jun 20, 2015)

at the risk of repeating myself.....
"whats the guy really want? $20?, $50? $100?" 
:devil3:


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## Gary in WA (Mar 11, 2009)

Sounds as if you live in either a high wind area or a seismic zone and the roof is your shear diaphragm... required perimeter blocking on the sheathing attached to each side. IT should be in the truss papers which is probably where he read it, double blocking may be required to get the shear resistance rated for your area under the newer I-codes; pp 456, Trusses-------- pp. 456 and on pp. 461, notice footnote "b" requiring blocking at the plywood joints for shear roof, are there H-clips installed on all the rest? And usually the vent block requires nailing because it is the low perimeter with the ridge at the high perimeter. http://codes.iccsafe.org/app/book/content/PDF/2012 International Codes/IBC/Chapter 23-Wood.pdf Ask him to show you where on the truss papers or the wind/seismic zone you may be in, to help us understand better. I had to install single blocks at perimeter (top sheets all the way across ridge- both sides) for nailing, as did I nail the lower vent blocking, only on 5 or so roofs, back in 2003, then I went to remodel- need to know 1/6 as much (as residential construction) doing that...

Gary


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## tornstrom (Sep 5, 2012)

Gary in WA said:


> Sounds as if you live in either a high wind area or a seismic zone and the roof is your shear diaphragm... required perimeter blocking on the sheathing attached to each side. IT should be in the truss papers which is probably where he read it, double blocking may be required to get the shear resistance rated for your area under the newer I-codes; pp 456, Trusses-------- pp. 456 and on pp. 461, notice footnote "b" requiring blocking at the plywood joints for shear roof, are there H-clips installed on all the rest? And usually the vent block requires nailing because it is the low perimeter with the ridge at the high perimeter. http://codes.iccsafe.org/app/book/content/PDF/2012 International Codes/IBC/Chapter 23-Wood.pdf Ask him to show you where on the truss papers or the wind/seismic zone you may be in, to help us understand better. I had to install single blocks at perimeter (top sheets all the way across ridge- both sides) for nailing, as did I nail the lower vent blocking, only on 5 or so roofs, back in 2003, then I went to remodel- need to know 1/6 as much (as residential construction) doing that...
> 
> Gary


Thanks for that info! I'm waiting to hear back from the truss manufacturer. The inspector where it clearly says I don't need edge support on the 1/2" ZIP panels (they are good up to 28" span), but still says I need the ridge blocking.. so mixed messages. This is in Bastrop county, TX. Maybe there are some high wind codes that I need to follow. If there are, I wish I was told about those at the framing inspection.


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## tornstrom (Sep 5, 2012)

Solved. I talked to the head inspector in the city, and he too agreed with me. It's the decking material used that decides if you need blocking or not, not any specific code in the IBC. The 1/2 Zip panels do not require edge support or H-clips. I presented that to the inspector and he agreed that I was right and took that item of the list. Thanks Gary in WA for pointing me to that table!


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## mgp roofing (Aug 15, 2011)

FYI, edge blocking is required on all shingle roofs' ridges & eaves in my area ( New Zealand). Probably because of earthquake risk.


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## ront02769 (Nov 28, 2008)

Along the same lines, I am currently working on two habitat builds about 40 miles apart. One is about 15 miles from ocean and we are required to run continuous blocking along the top of the trusses 2" down from the peak on each side. Along with blocking at every plywood seam extending in 4' from each corner. For the other one, nothing due to difference in wind zone. Ron


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