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Thread: JOIST OPENING

  1. #1
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    Default JOIST OPENING

    HEY ALL

    glad the world didn't end.

    found this hole in basement ceiling joist--is this correct. or is it damaging support

    thanks

    cvf

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  2. #2
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    Default Re: JOIST OPENING

    Allowed only if included in the desigh.
    FWIW I don't think it would be a problem.

    ' correct a wise man and you gain a friend... correct a fool and he'll bloody your nose'.

  3. #3
    James Duffin's Avatar
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    Default Re: JOIST OPENING

    If it's okay to put a 10" hole in the joist for ductwork then that hole ain't nothing!


  4. #4
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    Default Re: JOIST OPENING

    After enlarging the photo I see that the holes are over the joist saddle. This can cause the joist to crush at the saddle.
    May not cause a problem, but could.
    Call it out.

    ' correct a wise man and you gain a friend... correct a fool and he'll bloody your nose'.

  5. #5
    James Duffin's Avatar
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    Default Re: JOIST OPENING

    I agree the hole should not be there unless the hole is a knockout.

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  6. #6
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    Thumbs down Re: JOIST OPENING

    Yes the PRI behind the light is damaged, yes it is a problem, as is the hanger. The flange is ripped out to the bottom chord at the centerline of the hole/knockout which is too close to inside edge of support. The photo displays damage to the bottom chord compression/crushed. The hanger altered/notched, bottom pinned, flange opening w/in 2" of PRI end, beyond inside edge of support - within bearing/support face!

    No exemption for knockout should this have initially been one before PRI was altered in length - if had been knockout as opening is ripped to chord and w/in support/bearing face.

    There are several other areas/issues of concern also, including besides framing/structural support.

    That appears to be gyp board upon the underside of a stair on the left. Presumably this is the support for the landing and basement door threshold with a "hung" pre-fab utility stair to the basement from the floor above.

    I have more concerns regarding structural framing/failures besides the PRI end flange, chord and altered mis-applied hanger, can't see what I'd want to investigate further. UKn spans or loading.

    Clickable link to ESR-1405 (which is also attached):

    http://www.icc-es.org/reports/pdf_fi...S/ESR-1405.pdf

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  7. #7
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    Default Re: JOIST OPENING

    No it's not OK..sheesh look at that workmanship. First red flag is it's not round. A hole must be round for it not to weaken the structure. Not to mention all the other problems noted here.


  8. #8
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    Default Re: JOIST OPENING

    This hole is not ok most manufactures would require some sort of repair and removal of the wires from this location. As you can see from this link holes are not allowed in or near the bearing points.
    http://www.bc.com/dms/wood/ewp/3_Gui...l_complete.pdf


  9. #9
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    Default Re: JOIST OPENING

    Notice the type of wires and cables these are. It is not Romex

    The hole is not the major problem...The problem is "Acme Video Sound and Security Systems"! Most of these guys know how how to hook up a complicated Audio/Video system...And can probably program your VCR to stop flashing 12:00-12:00-12:00-12:00...

    But they (most of them) are not trained in any type of construction code...That is why one hole for all cable is found here.


  10. #10
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    Default Re: JOIST OPENING

    Quote Originally Posted by paul hardy View Post
    This hole is not ok most manufactures would require some sort of repair and removal of the wires from this location. As you can see from this link holes are not allowed in or near the bearing points.
    http://www.bc.com/dms/wood/ewp/3_Gui...l_complete.pdf
    Agreed, check the manufactures design manual. Can't have holes at bearing points.

    Randy Gordon, construction
    Michigan Building Inspector/Plan Reviewer

  11. #11
    Richard Anderson's Avatar
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    Default Re: JOIST OPENING

    I had came across the same and asked a HVAC contractor and he said they do this with ducting all the time BUT before any holes are made an engineer must OK it, you can ask the home owner if it had been approved, it is allowed but how and where is the concern. In my case the HVAC tech missed his floor vent by three feet and drilled another hole in the same joist, not good.


  12. #12
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    Default Re: JOIST OPENING

    Quote Originally Posted by James Duffin View Post
    If it's okay to put a 10" hole in the joist for ductwork then that hole ain't nothing!
    Not really James... a 10" hole in the center of the span may be fine, a 2" hole at the bearing end of the joist could spell disaster.

    Randy Gordon, construction
    Michigan Building Inspector/Plan Reviewer

  13. #13
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    Default Re: JOIST OPENING

    Quote Originally Posted by Richard Anderson View Post
    I had came across the same and asked a HVAC contractor and he said they do this with ducting all the time BUT before any holes are made an engineer must OK it, you can ask the home owner if it had been approved, it is allowed but how and where is the concern. In my case the HVAC tech missed his floor vent by three feet and drilled another hole in the same joist, not good.
    Holes at the bearing points are not good, holes toward the center of the span are allowed to be quite large. The reason is because at the bearing, you can get weight that will actually buckle or bow the center at the OSB web.

    In the center of the joist without a wall or a bearing to hold the bottom of the joist, it would be impossible for the joist to bow in the center. It would just deflect both the top and bottom cords simultanously.

    Randy Gordon, construction
    Michigan Building Inspector/Plan Reviewer

  14. #14
    James Duffin's Avatar
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    Default Re: JOIST OPENING

    Quote Originally Posted by Door Guy View Post
    Not really James... a 10" hole in the center of the span may be fine, a 2" hole at the bearing end of the joist could spell disaster.
    I added a post after my first post that says I agree with you...


  15. #15
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    Default Re: JOIST OPENING

    Quote Originally Posted by James Duffin View Post
    I added a post after my first post that says I agree with you...
    Sorry James, I missed it. Thanks for the pdf, a picture speaks a thousand word somtimes.

    Randy Gordon, construction
    Michigan Building Inspector/Plan Reviewer

  16. #16
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    Default Re: JOIST OPENING

    Quote Originally Posted by Door Guy View Post
    Holes at the bearing points are not good, holes toward the center of the span are allowed to be quite large. The reason is because at the bearing, you can get weight that will actually buckle or bow the center at the OSB web.

    In the center of the joist without a wall or a bearing to hold the bottom of the joist, it would be impossible for the joist to bow in the center. It would just deflect both the top and bottom cords simultanously.
    It's actually a function of bending moment and shear. The bending moment is greatest at the center of the span of a simply support beam (or joist), and the shear is smallest at the center. This places the top flange in compression and the bottom in tension. The center (or neutral axis) sees little stress. That's why holes in the web are okay away from the supports, but notches in the flanges, which take the tensile force at the bottom of the beam, are a no-no.

    That's also why an I-beam has the shape that it has (wide flanges and a narrow web). The flanges take the tension and compression. If the top flange is not braced (by floor framing, for example), the joist/beam could buckle.

    At the ends of the joist, the shear is the greatest, but the bending moment is the smallest (zero). Shear restistance relies on the area of the member, so reducing teh area via notches or holes is prohibited.


  17. #17
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    Default Re: JOIST OPENING

    I've worked as a carpenter for several years and this problem should have been taken care of in the design of the house. The I-joists should NOT have ANY additional holes in them other than the knockouts that the manufacturer provides based on the plans that they receive. If you want to put additional holes, it should be ok'd by an structural engineer. These joists are very strong when properly installed and have been used for years in commercial buildings. In recent years I've been seeing them more and more in new residential construction. The problem starts when there are no plans for the different trades to go by. The plummer, HVAC, etc. installers don't know enough or care enough to use the knockouts or get approval to make new holes from an engineer. They will do what is most convenient and least expensive.

    Check to see if the manufacturer's name is on the web. If it's there, you can contact them by e-mail and most of them will give an answer if it is safe. Some will even send out a representative free of charge. If I were you I'd note it in my report and recommend that it be further inspected.


  18. #18
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    Default Re: JOIST OPENING

    Quote Originally Posted by Pete Bucey View Post
    I've worked as a carpenter for several years and this problem should have been taken care of in the design of the house. The I-joists should NOT have ANY additional holes in them other than the knockouts that the manufacturer provides based on the plans that they receive. If you want to put additional holes, it should be ok'd by an structural engineer. These joists are very strong when properly installed and have been used for years in commercial buildings. In recent years I've been seeing them more and more in new residential construction. The problem starts when there are no plans for the different trades to go by. The plummer, HVAC, etc. installers don't know enough or care enough to use the knockouts or get approval to make new holes from an engineer. They will do what is most convenient and least expensive.

    Check to see if the manufacturer's name is on the web. If it's there, you can contact them by e-mail and most of them will give an answer if it is safe. Some will even send out a representative free of charge. If I were you I'd note it in my report and recommend that it be further inspected.
    I joist that I have gotten in the past 5 - 7 years don't have any knockouts in them. However, they should come with a design manual for drilling holes.

    Randy Gordon, construction
    Michigan Building Inspector/Plan Reviewer

  19. #19
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    Default Re: JOIST OPENING

    Quote Originally Posted by Door Guy View Post
    I joist that I have gotten in the past 5 - 7 years don't have any knockouts in them. However, they should come with a design manual for drilling holes.
    I just inspected some I-Joists ("just" as in about a month ago) and they all had a series of small round knock-outs not too far up from the bottom.

    I've forgotten what the installation instructions stated for the largest hole allowed, but any two holes had to be at least twice the diameter of the larger hole apart from each other, measured hole edge to hole edge. I.e., a 4" hole had to have 8" of I-Joist web material between it and another 4" or smaller hole.

    Jerry Peck, Construction / Litigation Consultant
    Construction Litigation Consultants, LLC ( www.ConstructionLitigationConsultants.com )
    www.AskCodeMan.com

  20. #20
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    Default Re: JOIST OPENING

    Quote Originally Posted by Jerry Peck View Post
    I just inspected some I-Joists ("just" as in about a month ago) and they all had a series of small round knock-outs not too far up from the bottom.

    I've forgotten what the installation instructions stated for the largest hole allowed, but any two holes had to be at least twice the diameter of the larger hole apart from each other, measured hole edge to hole edge. I.e., a 4" hole had to have 8" of I-Joist web material between it and another 4" or smaller hole.
    Must be we are using a brand that stopped using them. Electricans could never use them anyway. When you would knock them out it would create a hole in the web about twice the size of the knock out. They just started drilling their own holes. They never line up with each other and wires looked like a snake trail. Not to keen on the knock outs... the ones we used were worthless and a waste of the manufactures time putting them in.

    Randy Gordon, construction
    Michigan Building Inspector/Plan Reviewer

  21. #21
    Daniel Leung's Avatar
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    Default Re: JOIST OPENING

    Quote Originally Posted by Jerry Peck View Post
    I've forgotten what the installation instructions stated for the largest hole allowed, but any two holes had to be at least twice the diameter of the larger hole apart from each other, measured hole edge to hole edge. I.e., a 4" hole had to have 8" of I-Joist web material between it and another 4" or smaller hole.
    Jerry you are correct! for this website : Engineered Wood
    "Uncut length of web between adjacent holes must be twice the length of the large hole dimension"
    Also, "Up to 1.5" diameter hole allowed anywhere in web closest spacing =1'-0" o.c."


  22. #22
    Floyd Thorne's Avatar
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    Default Re: JOIST OPENING

    Is this not an engineered joist? I don't believe this is O.K. anywhere, even here in the South....


  23. #23
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    Default Re: JOIST OPENING

    The joist in front of the light has a knockout open already, then they drilled another hole right next to it.

    On the joist you will usually see "ESR-1234" printed somewhere. Then go to the ES site at was pointed out by Mr. Watson and find the ES report for the specific joist.

    You do not need engineer's permission to drill holes in uniformly loaded joists as long as the hole are in accordance with the ESR.

    The other questions would be: are the holes round? Are they 1-1/2"or less?

    If I was a betting man, I would wager those holes are not compliant. However, you will need to look at the instructions for the specific joist pictured.


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