Detached garage remodel to apt. I have been drilling holes in studs ,(80 year old Dade County pine), and it's starting to look like Swiss cheese. Is it possible to use some of the holes to hold two (2), 12/2 nm without creating a potential problem? This would be for bathroom light and outlet cgfi circuit and one of the bedroom receptacle circuits. I understand that bundling has to be figured into, as regards capacity. Thanks, Ken

A very general rule of thumb; you can run up to four cables in a hole as long as the hole is big enough to not damage the cables.

I normally go three of this type:
12-2
14-2
12-3 (Mixed) with the above

Once the wire gets over 12AWG NM, then things change.

Yet,

Stan is 100% correct. The hole size is very important!

I have a question (Yes, I'm hijacking this thread--some what):

In your opinion, when do you consider the wires bundled--when running them horizontally through bored holes?

Me personally: I don't. I just believe the wires should be installed maiking sure other wires can be pulled through easily. Once it feels a little tight, I'm done. Yet, this can be a long debate, if we consider derating, and yada... yada... yada...

Maybe I shouldn't have asked! :D

A very general rule of thumb; you can run up to four cables in a hole as long as the hole is big enough to not damage the cables.Thank you for answering my question, it was very helpful, Ken.