# max hole size on 2x4 top and bottom plate



## BlueBSH (Oct 29, 2009)

I need to run some DWV vent through 2x4 walls that are non-load bearing walls.. what is the max hole size for this situation? just trying to figure out if i can retro fit 1 1/2 or 2" PVC vertically through that space...thanks!


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## TarheelTerp (Jan 6, 2009)

BlueBSH said:


> I need to run some DWV vent through 2x4 walls that are non-load bearing walls.. what is the max hole size for this situation? just trying to figure out if i can retro fit 1 1/2 or 2" PVC vertically through that space...thanks!





IPC said:


> F101.3 Bored holes. A hole not greater in diameter than 40
> per-cent of the stud width is permitted to be bored in any wood
> stud. Bored holes *not greater than 60 percent of the width of the
> stud is permitted in non-bearing* partitions or in any wall where
> ...


3.5 x 60% = 2.1"
3.5 x 40% = 1.4"


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## sublime2 (Mar 21, 2012)

Looks like your good to go!


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## bcgfdc3 (Jan 28, 2012)

Just a question. The 60%/40% is that for vertical studs? I beleive the OP is boring the top plate and bottom plate. Could you completely bore the top and bottom plate in a non load bearing wall?


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## BlueBSH (Oct 29, 2009)

bcgfdc3 said:


> Just a question. The 60%/40% is that for vertical studs? I beleive the OP is boring the top plate and bottom plate. Could you completely bore the top and bottom plate in a non load bearing wall?


thats actually one of the reasons i was asking.. ive seen examples online where they cut the plates out completely and just put nail guards across.. but wasn't sure if that is allowed now or not


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## sublime2 (Mar 21, 2012)

The calculation applys be it vertical or horizontal. Metal plates are recommended .


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## ratherbefishing (Jan 13, 2011)

If it wasn't allowed, how would any bathrooms be vented?


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## AndyGump (Sep 26, 2010)

This should help.

Taken from the 2009 IRC.

Andy.


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## psilva8 (Jan 12, 2012)

Assuming the framing is done correctly, it is not uncommon to see a section of top or bottom plate completely cut out even in a load bearing wall. Happens all the time.


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## BlueBSH (Oct 29, 2009)

AndyGump said:


> This should help.
> 
> Taken from the 2009 IRC.
> 
> Andy.


 
so... this is allowed if im reading the picture right as long as its strapped and fireblocked


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