Home>Discussions>ELECTRICAL & LIGHTING>Drilling through a large header
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Pediwent
Drilling through a large header

I have a 4 by 8 header running over the rough opening for a sliding door and I need to drill up through it to run wires for a switch positioned next to the door. Would doing that affect the structural integrity of the beam?

A. Spruce
Re: Drilling through a large header

The size and location of the hole and the bearing load will determine the ill effects on the beam. If you can avoid drilling the beam, you should.

canuk
Re: Drilling through a large header

Bad idea .

Run the cable through a stud bay,

Re: Drilling through a large header

Is the beam only over the rough opening? Or does it continue to either side? If to either side go up through the header of the stud walls to the side if you can (which should just be a 2x4 header) that or go horizontally through a few studs depending on where you need to locate the wires.

If you can't avoid that then go up through that 4x8. That is a pretty darned big piece of wood and a small, 1/4" hole shouldn't impact the load bearing ability of it too much, though drill the smallest possible hole.
-Matt

Pediwent
Re: Drilling through a large header

Thanks for the replies. The header is not engineered, it is a piece of dimensional lumber. It extends past the rough opening about two feet, where it butts into a large, vertical support beam. It is held up by a 4 by 4 that is placed against that support beam, which is why it would also be problematic to drill horizontally. It is held up at the rough opening by 2 2x4's nailed together. The door opening is on the garage level and there is a single story above. So the section I want to drill through is between the rough opening and the trimmer stud against the vertical beam. I've got to run 4 pieces of 14/2 Romex through the header, so it would probably be best to drill two 5/8" holes rather than a single 1" hole.

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canuk
Re: Drilling through a large header

Close to the trimmers as possible. Holes should be spaced 1 inch minimum from each other.

A. Spruce
Re: Drilling through a large header

Question, if either side of the opening is all 2x4 and 4x4, where will these wires be running to? It sounds like there isn't room for switch boxes either.:confused:

Pediwent
Re: Drilling through a large header

There is actually close to 2 ft between the trimmers at the rough opening and the trimmer at the end of the header. I'm installing a two gang box in that cavity for switches to control the interior and exterior lighting.

A. Spruce
Re: Drilling through a large header
Pediwent wrote:

There is actually close to 2 ft between the trimmers at the rough opening and the trimmer at the end of the header. I'm installing a two gang box in that cavity for switches to control the interior and exterior lighting.

With this in mind, then I wouldn't worry too much about two small holes to pull your wires, because the trimmer for the door opening and the trimmers at the end of the header will more than make up for them. As I recall, you can pull two 14/2 romex cables through a 3/4" hole. If you drill one hole at the door trimmer and one on the other side of the stud bay at the header trimmer, you will not significantly change the structural value of the header.

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