Holes in floor joist

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tdaug53

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My helper drilled one 7/8" and one 2-1/2" hole 55 inches from supporting wall in a basement floor joist wich is a 2x10 is this ok?
 
How long is the span? I have drilled 2.5" holes in 2x10 joists with no issue but it depends on where he drilled it.
 
tdaug53 said:
My helper drilled one 7/8" and one 2-1/2" hole 55 inches from supporting wall in a basement floor joist wich is a 2x10 is this ok?
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Most places limit the size of the hole to a percentage of the framing member. I think you're ok with a 2 &1/2" hole as long as it's in the middle 1/3 of the framing member. If it's in either of the other 2/3's,,,,,you will need framing plates to fix it.
 
This may help

Example to calculate safe areas​
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Measure the clear span between supports and the joist height.
E.g. 3.0 m (10’0”) and 150mm (6”).
Figures in bold type are constants.
Safe area for drilling lies between ....​



0.25 x 3.0 (10’0”) = 750mm (30”) and


0.40 x 3.0 (10’0”) = 1200mm (48”)


The maximum diameter of hole is ....​


0.25 x 150mm (6”) = 38mm (11/2”)​


So safe areas to drill are from 750 to 1200mm from either end and up to 38mm diameter.

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The span is 20' room. He was drilling holes for home runs. He had six other 7/8 holes starting about two foot from outside wall
 
Sounds like a 2x10 may not work with a 2.5" hole. I believe what we did was to put 2 pieces of 3/4" plywood on both sides of the joist about 4' long and then drill the center of the plywood both length and width.
 
We did a 11,000 sq ft home some 5 yrs ago with night mare framing and from garage down large hall way to main rooms on lower level we had to bring some 35 home runs down that hall way area , this framing was TGI rafters but in 3 areas there was some kind of special framing between these TGI an I cant remember what it's called but we had to have the structural engineer come out to survey what we had planned to do , I told the owner we would not drill a hole until the engineer gave the approval , he gave the approval no larger than 1 1/4 inch holes max 10 holes spaced out 4 in apart , this house had the lighting panels in it like 8 of them with electronic relays , crazy job to.
 
International Residential building code R502.8.1 Sawn lumber
2" minimum from top or bottom. D/3 max.
The diameter of holes bored or cut in to members shall not exceed one-third the depth of the member. Holes shall not be closer then 2" to the top or bottom of the member, or to any other hole located in the member.
 
acrwc10 said:
International Residential building code R502.8.1 Sawn lumber
2" minimum from top or bottom. D/3 max.
The diameter of holes bored or cut in to members shall not exceed one-third the depth of the member. Holes shall not be closer then 2" to the top or bottom of the member, or to any other hole located in the member.
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We really ought to forward this info to the plumbers.... I see some things that are not mentionable getting done.:roll:
 
When they cut out large holes they gusset with plywood as I described earlier. Apparently you can make a larger hole when you gusset with plywood on both sides.
 
Dennis Alwon said:
When they cut out large holes they gusset with plywood as I described earlier. Apparently you can make a larger hole when you gusset with plywood on both sides.
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Really, every time?
Not in the real world, that is why there are these guy called building inspectors. Gusseting with plywood is not a code recognized method of "fixing" an over sized hole or notch, you need to double up joists or use engineered brackets. Even then you are limited to what you can get away with.
 
Dennis Alwon said:
When they cut out large holes they gusset with plywood as I described earlier. Apparently you can make a larger hole when you gusset with plywood on both sides.
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If holes and notches occur in sawn lumber that exceeds code limits, we have to require an engineered fix, because there are no perscriptive fixes in the code. Structural panel gussets are one fix I typically see. If engineered lumber has been used like I-joists, LVL's, etc, and the manufacturer's chart limitation are exceeded, then an engineer must be used.

I almost never see any framing issues with wiring methods unless it is a SE cable or feeder going through an exterior wall top plate.

For the most part, I see plumbing causing the most butchering issues.
 
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