Replies

1. 
   unclemike42 | Jun 10, 2022 06:21am | #1

   https://www.fp-supply.com/cmss_files/imagelibrary/I%20Joists/Allowable-Holes-I-Joists--amp--Beams.pdf

   You can verify i joist brand and look for specific guidance that applies.

   It depends on the dimensions of the joist, and the type. and how close to supports the hole is.

   Those holes look large enough to want to look up guidance on the holes.

1. 
   J0nn | Jun 13, 2022 03:14pm | #3

   Thanks for the link. It’s hard to read compared to guidance for dimensional lumber. I think the bottom line is that only 1/8 of an inch of web need be left and the flange should never be touched. The tables seem to be guidance for where the I beam is sitting on the load bearing wall. Upon further reading it seems that the web is there mainly to keep the upper and lower flanges in place. Compression occurs on the upper flange and tension on the lower. Just like the metal on bridges if you have ever done stress analysis. Some web is needed to create this dynamic, just like cross members on a bridge span, but not nearly as much as seems natural (I think) especially when compared to dimensional lumber.

1. 
   rww0002 | Jun 14, 2022 09:59am | #5

   I think you are misreading the table. Depending on the depth of the joists (it is hard to tell by your photos how deep they are), you will still have size limitations and it gets more restrictive the closer to bearing you are.
   You are correct that the web is not as important and the flange, but the 1/8" minimum is in addition to the max hole size noted in the chart.

   For example - for 11 7/8" joists, the maximum hole dimension is 8 7/8" and must be further than 6' from the bearing or supports and can be no closer to one of the flanges than 1/8". Also, only one of these large holes would be permitted per joist.

   I cannot tell by the photos if the holes meet the max hole size limits or not, but they sure look terrible, especially if that wire is all that is being run through there..

1. 
   J0nn | Jun 14, 2022 11:21am | #7

   Thanks for the clarification. The hole is not near bearing, but there are other large holes side by side that do not meet spec as per the tables. Maybe we should bring it up with the builder. I suppose the holes could be patched with glue in place plywood?

1. 
   rww0002 | Jun 14, 2022 11:46am | #9

   I would definitely bring it up with the builder. this is very poor workmanship. There are likely fixes available through most suppliers but I would push for a supplier-approved detail so that you do not void product warranty.

   From your photo it looks like one of the top flanges is cut as well (hard to see exactly what is going on , but the second joist in to the right side..)

   This is not acceptable for new construction and you should not accept the work. push for a supplier-approved fix or replacement (and not at your cost).

2. 
   greg_e | Jun 14, 2022 04:43pm | #10

   The manufacturer of the I joists can offer guidance on repair of the joists. The builder definitely needs to fix it.

2. 
   firedudec56 | Jun 11, 2022 09:31pm | #2

   since the holes were not actually "drilled/hole sawed", I'd be concerned. There's very specific guidance to cutting into the web of I-joists (as well as solid stock framing) and those look like trouble
   I have an old house (1904 on porch column base) that has some 4x6 framing that's down to maybe 2x stock thanks to plumbers of the past.
   if I get ambitious. I'll try for some pictures.

   good luck

1. 
   J0nn | Jun 13, 2022 03:20pm | #4

   From what I have read since posting, very large holes are allowed in I beams. These holes “ don’t look right” compared to dimensional lumber. From what I gather, the guidance on dimensional lumber is to drill in the middle since the upper part undergoes compression and the lower part tension. And the hole can only be something like 1/3 of the total height.The flanges on ibeams take these loads so the same rules do not apply when it comes to the size of holes in the web that is allowed. The inch that was left should be fine from what I understand.

1. 
   rww0002 | Jun 14, 2022 10:10am | #6

   This is not right. See comment above.. While the holes allowed are larger than dimensional lumber, there are still max hole sizes, and allowable hole size gets smaller the closer you get to supports.

   I think generally the max hole size at midspan is something like 3" less than the joist depth, but it varies a bit by manufacturer. - see table linked above

1. 
   J0nn | Jun 14, 2022 11:22am | #8

   Yea, is just so hard to believe that the trades person mucked this up so badly

1. 
   calvin | Jun 15, 2022 06:28pm | #11

   I wouldn’t give him/her the compliment of “trades” in their title.