ECN Forum Forums General Topics of the Trade General Discussion Area Drilling beams?

What is the story on drilling through wood beams? 5" thick 12" high.

you lost me Redsy

can't i just drill it?

To completely confuse things:

Hixson (Mining and Electrical P.E.) said "Always drill dead center"...

McClung (Archetect, GC) says: "Drill in upper third near endpoints, lower third in the middle of the beam..."

I say... "Drill wherever is most convenient..."

Heck, in my mood right now, I'd take a sawzall and completely remove the sucker...

sparky,
I think some limitations are placed on drilling beams. I was retrofitting some recessed cans, and when I cut a small section of ceiling away to notch what I thought was a floor joist, I noticed that it was 5" wide. I opened up the hole some more and it appears to be a long beam. I don't thing it's OK to drill through, but I don't do much new residential work, so I thought someone here would know.

sparky66wv,

relax, and ask your girl for a massage.

[This message has been edited by Redsy (edited 11-03-2001).]

My mistake. It was an engineered wood product beam. In case it makes a difference.

[This message has been edited by Redsy (edited 11-03-2001).]

Better be careful what you drill! Structural engineers get real up tight when you make Swiss cheese out of their design. In housing I think it is drill the center but only in the outer third. I could be wrong, as I don’t do housing. In commercial work you better get the blessing of the structural engineer before you drill any structural member. God help you if you drill a glue lamb! It can be done but only with good reason and close structural supervision.
I did a restaurant a while back where the entire dinning area roof structure was wood framed with plywood sheeting on top and exposed tongue and groove below. We were not allowed to drill ANYTHING! No way forget it not in this lifetime. Ok, how do we get all the electrical in?
Well, we ended up having to run everything through a little void created by the plastered underside of the rafter tails around the perimeter. I’m talking multiple ½, ¾ and 1”conduit. At each point where there was a fixture or device we turned into the building parallel to the framing members. What a pain!
Moral of the story: Don’t drill unless you have permission. You may be paying some carpenters to replace their work.

Nick,

Glue lamb?

Maybe it is spelled as a compound word. I don’t know. (I am a terrible speller) They are very common in this part of the country in light commercial buildings. Mostly, but not limited to, concrete tilt ups. If you haven’t seen one they are made from multiple layers of wood pressed and glued together. They are used as main structural support

Redsy,

The 'Lam' is as in Laminated.
Multiple layers of pressed wood, plywood etc. Strong stuff. Where is this beam? I doubt that you drilling a small hole through it will weaken anything.

Bill

[This message has been edited by Bill Addiss (edited 11-04-2001).]

I do a lot of residential these days, which is'nt my first choice , but feeds the fam. I'll typically drill out with milwakee self-feed bits. If the hole is large enough , and it has obvious space around the conductors, it is not 'bundled', the rationale being heat captivated. So i drill big holes, especially home runs back to the MDP. The thing about the self-feeds & a right angle, is they are straight, the pull is without strain, goes smoothly. One of the most congested area's, as well as site specific, is the kitchen. As bearing walls are usually 2x6", a 1 1/2" centered run is OK. Besides, the plumbers are usually the first focus of any structual meddling. Most carpenters i've asked ask for a centered hole in beams.