Drilling through exterior walls

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Moe

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Is anyone familiar with code related to drilling through dimensional 2x4s for exterior walls?

I currently have a drain pipe that is installed on an exterior wall, but it is notched out of about 4 studs (1 is a jack stud for a window, the other 3 are studs below a window).

I would like to get the drain pipe in the wall completely so I can sheetrock... Should I sister all the notched beams, and then drill a 2" hole through each notched/sistered beam?

Double sister each beam?
 
From https://www.familyhandyman.com/walls/drilling-holes-notching-and-boring-holes-in-wood-studs/

  • Holes in bearing wall studs (exterior and interior walls that bear the weight of the roof and/or other stories above) may not exceed 40 percent of the width of the stud.
  • Notches in bearing wall studs may not exceed 25 percent of the stud’s width.
  • Holes in non-bearing walls can’t exceed 60 percent of their width.
  • Notches in non-bearing walls can’t exceed 40 percent of their width.
  • The edge of a hole must be at least 5/8 in. from the edge of a stud.
To appease the plumbing gods, the codes have made at least one notable exception: In bearing walls you can bore 60 percent size holes—as long as you double up the studs and don’t drill through more than two successive pairs of these doubled-up studs (Fig. A). This allows you to run a short section of “drain, waste, vent” (DWV) pipe through a 2×4 wall without beefing up the whole wall to 2×6 dimensions.

There are other, less specific guidelines:
When possible, notch a stud near the top, rather than the bottom. Don’t locate holes and notches near large or loose knots, and don’t group too many in the same area of the stud. Finally, notch only when necessary; holes weaken it less than notches.

Dorky illustration at https://cdn1.tmbi.com/TFH/Attachments/FH00JUN_NOTBOR_01.pdf
 
I'm sorry but you really shouldn't notch, like frodo said, remove notched things and replace them with drilled
 
Double the studs, use Simpson Stud shoes to reinforce the holes, and follow their fastening directions to the letter. I’d recommend the HSS2 versions, because they allow the use of the sds screws for attachment. They are approved under the ICC codes, and most others.
 
Doesn't look like holes would work either.

Code reads:
-Holes in non-bearing walls can’t exceed 60 percent of their width.
-The edge of a hole must be at least 5/8 in. from the edge of a stud.


The pipes I see in those pictures cannot meet these code requirements.

Opps...wrong thread with similar problem
 
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R602.6 Drilling and Notching of Studs

Drilling and notching of studs shall be in accordance with the following:
  1. Notching. Any stud in an exterior wall or bearing partition shall be permitted to be cut or notched to a depth not exceeding 25 percent of its width. Studs in nonbearing partitions shall be permitted to be notched to a depth not to exceed 40 percent of a single stud width.
  2. Drilling. Any stud shall be permitted to be bored or drilled, provided that the diameter of the resulting hole is not more than 60 percent of the stud width, the edge of the hole is not more than 5/8 inch (16 mm) to the edge of the stud, and the hole is not located in the same section as a cut or notch. Studs located in exterior walls or bearing partitions drilled over 40 percent and up to 60 percent shall be doubled with not more than two successive doubled studs bored. See Figures R602.6(1) and R602.6(2).


    Exception: Use of approved stud shoes is permitted where they are installed in accordance with the manufacturer's recommendations.
drilling a 2 1/8'' hole for a 1 7/8 pvc pipe is approved under the exception as long as stud shoes are installed



2.jpg
 
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We do very little residential . What is a stud shoe ?

Wyr
God bless
 
It is a metal plate that has been bent into a flat bottomed U shape, that will fit over a 2x4 stud. It has a round section missing from the sides of the U to fit around a pipe, and has screw/nail holes to fasten it to the wooden stud. It's purpose is to reinforce the stud when it is necessary to drill a bigger hole through the stud than you would normally be allowed to.
 

And, these are not installed completely. They are missing fasteners. The side plates should be pulled in snug against the stud. Done right there are twelve fasteners required.

It is important that they are installed in strict accordance with the manufacturers instructions. And, if you are going to be inspected: I would advise having the instruction sheet ready, for the Inspector.
 

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