# Need to drill hole through rim joist for venting



## hammerlane (Oct 6, 2011)

old thread deleted


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## LMHmedchem (Aug 14, 2010)

Your local building inspector should have something like .pdf files on their website with that kind of information. A 5" hole would be far too big for a floor joist without some additional bracing, but a rim joist does not have the span load on it, so you may be able to do more. Also you need to be mindful of what is loaded on the beam at that point, as in from above.

*LMHmedchem*


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## hammerlane (Oct 6, 2011)

I believe the max hole size for 2x8 joist is 2-3/8 inch diameter


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## hammerlane (Oct 6, 2011)

found this:


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## LMHmedchem (Aug 14, 2010)

hammerlane said:


> found this:


This is for floor joists that span empty space. A rim joist is sitting on the foundation and so is supported along it's entire length. A rim joist can have a larger hole in it as long as there isn't a major support post anchored just above that location on the rim.

This is one site that gives structure codes, but it is not searchable.
http://publicecodes.citation.com/st/ny/st/b400v10/index.htm

I think the easiest thing to do is to call the building department and ask.

*LMHmedchem*


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## hammerlane (Oct 6, 2011)

LMHmedchem said:


> This is for floor joists that span empty space. A rim joist is sitting on the foundation and so is supported along it's entire length. A rim joist can have a larger hole in it as long as there isn't a major support post anchored just above that location on the rim.
> 
> This is one site that gives structure codes, but it is not searchable.
> http://publicecodes.citation.com/st/ny/st/b400v10/index.htm
> ...



I agree. Just posting the above for spanning joists


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## LMHmedchem (Aug 14, 2010)

hammerlane said:


> I agree. Just posting the above for spanning joists


It would be nice if the building codes were searchable, but I guess that would be a bit too much to ask.

I personally don't worry all the much about the rim joist, but I do make sure that I am going through a place without too much load over top. I would avoid areas of the joist whit a bearing wall above. If I have any reservations, I scab on a 3/4" plywood plate, or two, with adhesive and 3" deck screws like you would if you had to reenforce a large notch in a joist where a trap was run through.

Be aware, this is my opinion and practice, and you asked about code. You probably should contact the building department and ask. Just say you are thinking of doing something and want to know if it's allowed. They will probably say that rim joists are exempted and you are fine. There may not be anything specific in the code if it's exempted. I don't remember doing this for anything larger than a 3/4" copper pipe, so keep that in mind. Isn't there a windows you could use?

*LMHmedchem*


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