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Tool to notch a joist

stickshift

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Need to notch underside of ceiling joist to run some wires. Not enough room to use circular saw (nearby ceiling drywall). Tried carbide blade on oscillating multitool, but that's very slow (think it cuts metal quicker). What would GJ do?
 
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loganb

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Change the blade on the oscillating tool, a course tooth blade designed for wood will make fast work of it

In general though notching a bottom chord or rafter isn't a desired practice and should be avoided
 
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stickshift

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notching the bottom of a joist is not recommended as it will weaken and can cause it to split there . you may compromise the integrity & cause issues down the road, like home buyers inspections. can't you drill them?
Don't have access to drill anywhere near center of joist height.

I'm following the rules regarding notching (notch will be much smaller than max permissible notch; in fact, it will be just deep enough to fit the romex, then nail plate over it.
 
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stickshift

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Change the blade on the oscillating tool, a course tooth blade designed for wood will make fast work of it

In general though notching a bottom chord or rafter isn't a desired practice and should be avoided
Makes sense, thanks. That carbide blade has very fine teeth.
 

PCustoms

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A chisel? Should take 30 seconds, may require a hammer.

But I wouldn't notch a joist.
 

Jlbc212

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I've used a hand held, battery powered router to make notches in wood studs and joists. Mine is a Makita but I think Milwaukee makes one too.
 

ttmiller

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Why not use a right angle drill? I’d do just about anything to avoid notching.
 

James-W

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Use a small router with a straight cutter that is just wide enough and set the depth just deep enough to place the romex cable. Then cover it with the metal nail plate. As mentioned, it is not the best idea to notch a joist, but if you have no other choice in the matter then make the notch as small as possible.
 

danfromsyr

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maybe use surface molding and not notch the joist?
I've even used surface wire molding and a surface box to mount a ceiling light in a room w/o a central light.
 

joe_padavano

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Need to notch underside of ceiling joist to run some wires. Not enough room to use circular saw (nearby ceiling drywall). Tried carbide blade on oscillating multitool, but that's very slow (think it cuts metal quicker). What would GJ do?

This is a really, REALLY bad idea. Loads on joists put the bottom in tension. That's absolutely the last place you should cut. Unfortunately it appears that you've already made up your mind.
 
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stickshift

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Just as a followup, I didn't have a course tooth blade for my OMT (the suggestion I liked the best) (it's on my list for next trip to hardware store), so I ended up using Dremel + sanding drum (+ shop vac to limit dust) to create the very shallow notch needed to pass the wires.

To all the posts warning about notching underside of joist, yes, I understand the tension issue. This is a very short span (width of a stairwell), and the notch follows the rules regarding minimum and maximum distance from end of span. And as described, I'm well under the allowed depth and width of notch.
 
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tdkkart

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Just as a followup, I didn't have a course tooth blade for my OMT (the suggestion I liked the best) (it's on my list for next trip to hardware store), so I ended up using Dremel + sanding drum (+ shop vac to limit dust) to create the very shallow notch needed to pass the wires.

To all the posts warning about notching underside of joist, yes, I understand the tension issue. This is a very short span (width of a stairwell), and the notch follows the rules regarding minimum and maximum distance from end of span. And as described, I'm well under the allowed depth and width of notch.
Are you licensed, do you have a permit, have you shut off power and used proper LOTO procedures, do you know the inspector?

Geez, some people just need to get a life other than banging on a keyboard.
 

thr3squared

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Here's just a general trick for notching framing - mark the width of the notch with a pencil. The set the depth of your notch on a skill saw. Make a series of small cuts with the saw to remove material between your pencil marks. You'll end up with a series of little "fins". Then hit the fins with a hammer, they'll pop right out (surprisingly cleanly). Then if you'd like clean it up with a hammer and chisel.
 

malibu101

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Banging my keyboard here...

You should have made a groove. Like an upsidedown "U".
A notch means square corners, those can be stress risers.

I ain't got no degree in nothing though and don't read instructions.
 

Sumboodie

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Chainsaw.

My buddy did that for a window install. His wife was less than happy when she found sawdust on the bed. Haha
 

dutchgray

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Banging my keyboard here...

You should have made a groove. Like an upsidedown "U".
A notch means square corners, those can be stress risers.

I ain't got no degree in nothing though and don't read instructions.
I don't believe wood is notch sensitive like steel is wherein a small sharp corner or deep scratch can substantially reduce the strength, I believe when you notch a joist you reduce its strength to the equivalent dimension that remains. It will of course always fail where you notch it as that will be the weakest part.

I would never notch the underside of a joist, drilling in the centre third is preferred and a top side notch is allowed.
 

csp

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I'm shocked that nobody has said anything about Romex being run in a notch, regardless of the nailer. Where's the electrical safety police?!
 

Git

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