# OK to drill holes in top plate to run conduit?



## nap (Dec 4, 2007)

How do you think we electricians would do it any other way when we are installing something?

Go ahead and drill the holes. Like you stated per the IBC, as long as you do not drill excessively, you have no worries.


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## Termite (Apr 13, 2008)

2-1/4" would be the largest hole you can drill in a 5-1/2" wall. The concern I have is that your loads must be able to be transferred downward to the studs. So, if you have a joist or (even worse) a beam sitting on the top plate between two studs 16" apart, drilling a large hole would definately reduce the plate's ability to transfer those loads laterally to the studs. If your loads stack....Joists bearing directly above studs...No problem, drill away! Just know what you're drilling through before you do it! Keep your holes centered in the plate. Unless there's a serious point load where you drill, you probably aren't going to compromise the structure.

I would strongly suggest smaller holes if your loads don't stack, if it is a possibility. 

Adding metal straps across the top plate adds strength back to the top plate in tension, which is experienced in seismic and wind load events. For taking compressive loads on the plate such as a joist or beam, there would be little or no benefit.


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## troll5501 (May 10, 2008)

Thanks very much for both of your responses. 

KC, I mapped out the studs and joists in this section of the wall and attached a to-scale drawing below. The studs and joists have different spacing, but luck has it that the joists above the area I want to cut are almost stacked perfectly. Also there are some extra studs in this area probably because there is a stairway on the other side of the wall.

The orange indicates the proposed conduits/cuts through the bottom and top plates. The only thing I don't know is if there are any joints in the top plate. It's a 20' long wall (drawing shows only a 10' section). Please let me know what you think. 










Thanks!!


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## Termite (Apr 13, 2008)

Drill away! You should have no structural issues at all if you drill 2-1/4" holes at those locations. Totally legal and safe.


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