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To notch or drill for lines running through joists above..

To notch or drill for lines running through joists above..

Old 01-28-01, 10:25 AM
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I need to move power, hot and cold water, and a flex gas line up into the floor joists above. What's the general consensus on drilling versus notching?

Here's the area...

There's probably 20 joists that I have to go through. So I either have to drill 100 or so holes or notch 100 or so notches. If you look directly to the right of the HVAC trunkline, you'll see the support beam that the joist rests on for load reference.

Most all the DIY books I have say to notch is ok if not in the middle third of the joist span, but what do you guys think?

Old 01-28-01, 01:22 PM
Lew Falconer
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Hi TL. A good rule of thumb is never notch a floor joist no matter where it is. It weakens the joist too much and you would have far too many notches to do what you want. If you insist on moving everything into the joists, drill as small a hole as possible in the middle of the joist. I have another suggestion you might want to think about. You appear to have lots of headroom. You're going to have to box in the plenum anyway. Either extend the full depth box to encase the wiring etc. or box the wiring in with a half height box extended from the plenum box. This leaves your joist at full strength and doesn't really affect your headroom. The other option is to add 2"x2" lumber to the underside of your joists to lower the ceiling below the wiring and just be real careful where you put the screws into the drywall.
Let us know what you think.
Old 01-28-01, 01:26 PM
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Thanks Lew,

Allow me to demonstrate my lack of knowledge/experience in construction...

How about I squish (technical term) them all closer to the HVAC plenum?? Certainly there's some no no in that?

Old 01-28-01, 01:29 PM
Lew Falconer
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Squish away

I was going to suggest moving everything over but I had a Senior Moment and forgot. That would work fine and then the box for the plenum wouldn't be all that large. I think we've done it!
Old 01-28-01, 02:05 PM
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Lew has given you excellent advice and I like all of it.

I would NEVER notch these joists. Notching a joist on the bottom side is a very bad idea. I'm surprised that a DIY book would suggest it.

Personally, I'd just box them in as is. A simple box the same drop as the ducts will produce the simplest lines on your ceiling and keep your drywall job easier.

Moving the lines is good too, if you're up to the job. But I personally wouldn't go to all that trouble to narrow this soffit by less than two feet -- pretty small payback. You might enjoy the extra space some day when you want to run some more stuff through that soffit.

Old 01-30-01, 09:06 AM
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question for a question

Hello, refering to the above reply: "middle" being edge to edge middle not end to end middle
Now on with my question for the question: I recently heard that phone lines need to be sheilded from electric (romex). That might be something to check into. I am also interested.
Thanks for letting me put in my 2 sence.

P.S. The family handyman magazine had a great article in it about joists this last year. Seems like a moot point however, previous advise seems way smart.

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