1-1/2" deep multi-gang electrical boxes

Discussion in 'Electrical Forum discussion & Blog' started by Lakee911, Jan 14, 2008.

  1. Lakee911

    Lakee911 I&C Engineer (mostly WWTP)

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    Hey fellas,
    Does anyone know of a manufacturer that makes multi-gang (2, 3 or 4 gang)electrical boxes that are 1.5" or less deep? I need them for a basement remodel. 1" furring strips are being used over a concrete wall with 1/2" drywall over that.
    I did find some 1-1/4" deep single gang boxes, but they're limited to only single gang. :(

    Thanks,
    Jason
  2. jwelectric

    jwelectric Electrical Contractor/Instructor

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    use either a 4 square or a 4 11/16 with a 1/2 plaster ring.
  3. Lakee911

    Lakee911 I&C Engineer (mostly WWTP)

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    If I use a 4 square, I'm unable to mount any devices as they only have screws in the corners and they're 1.5" deep.

    Where can I find one that is 1" or 11/16" deep?

    Thanks,
    Jason
  4. jwelectric

    jwelectric Electrical Contractor/Instructor

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    sorry I should have said flat plaster ring and a jumbo plate cover.
  5. jwelectric

    jwelectric Electrical Contractor/Instructor

    Messages:
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    Location:
    North Carolina
  6. Lakee911

    Lakee911 I&C Engineer (mostly WWTP)

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    That first link won't look very nice in a finished basement. The second link doesn't work and the third is 2" thick. :(

    Any other ideas?

    I'm afraid I'll have to chip out the concrete behind a 2" device. :(

    Thanks,
    Jason
  7. Chris75

    Chris75 Electrician

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    1 1/4 is awfully shallow, can you fur the wall out a touch more? You are going to struggle with every receptacle and switch you install...
  8. jwelectric

    jwelectric Electrical Contractor/Instructor

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    The third can also be bought in a depth of 1 1/2 inches.

    I am giving you ideas not gathering material for you unless you have a check with my name on it and then if there is enough zeros on it I will even make the installation for you.
  9. Alectrician

    Alectrician DIY Senior Member

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    Simply tell them to properly fir it out 1 1/2" and do it with standard shallow boxes.


    If it's a basement I don't think you are supposed to chip out block.
  10. Chris75

    Chris75 Electrician

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    The problem your going to have even with 1 1/2 boxes is box fill, the way I see it is a 3x2x1 1/2 box is good for 7.5 cu. in., a 14-2 alone is 6 cu. in, so you wont even be able to install a device and make code... They make a 4" sq. by 1 1/4 which is good for 18 cu in plus the plaster ring... Your going to have to fur the wall out to meet code IMO.
  11. Lakee911

    Lakee911 I&C Engineer (mostly WWTP)

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    That's kind of harsh, jw. That third one does not, from all the research that I've done, exist in a 1-1/2" depth. So, I challenge you to find me one.

    As for the boxes that are made to accept a flat plaster ring that are 1-1/2" deep--that could work. I'll look into that.

    Otherwise, I'll just fir out the wall a little more and use a standard box.

    Thanks for your help, jw and everyone!

    Jason
  12. Chris75

    Chris75 Electrician

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    608
    Location:
    Litchfield, CT
    I personally would have just framed the walls with flat 2x4's, not sure of your building codes and insulation factor, but that could be a whole other issue...:D


    [​IMG]
    You can get these in 1 1/2 so with a 1/2 in plaster ring you would be fine. if you fur the walls out to 1 1/2 hope this helps you out.
    Last edited: Jan 14, 2008
  13. Lakee911

    Lakee911 I&C Engineer (mostly WWTP)

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    Hey Chris,
    That is a good point, but Carlon makes a box (http://www.homeandbeyond.com/prod-0010802.html) that is 1-1/4" deep and it's rated at 8" cu in. I've commonly heard that reffered to as a "switch box" and I believe their website says that it meets code for a switch or a receptacle. It has the UL stamp too. Anyhow.

    1 14/2+G: 1*2*2+1 = 5
    1 Yoke: 1*2 = 2
    5 + 2 = 7 < 8.

    I believe no clamp is needed for a 1G box. So, is that math ok? I would think that a 2G box that's 1-1/2" would be at least 19.2 cu in. Even 18 shoud be ok though.

    2 14/2+G: 2*2*2+1 = 9
    2 Yokes: 2*2 = 4
    2 clamps = 2
    9 + 4 + 2 = 15 < 19.2

    What do you think?
  14. Lakee911

    Lakee911 I&C Engineer (mostly WWTP)

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    Ok, everyone replying all at once! I guess I can't say I'm not getting help. :) I'm going to try that box, Chris with the flat plaster ring. Thanks.
  15. Chris75

    Chris75 Electrician

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    Location:
    Litchfield, CT
    14-2 w ground would equal 6 cu in, 2 for the black, 2 for the white, 2 for the ground...
    device (yoke) would be double volume allowance, based in largest conductor supported by the device. = 4

    I would say ney on the cable clamp,
    so your up to 10 cu in...

    so with a 4" sq new work plastic at 18 cu in, you could have 1 device, and two cables in the box and still be okay.
    Last edited: Jan 14, 2008
  16. Lakee911

    Lakee911 I&C Engineer (mostly WWTP)

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    You're right ... the grounds are all counted once, but still multiplied by the 2cu in per conductor for #14. So that makes it 8.

    I don't see how the device would be double volume allowance though. It should only be 2 for a single device, no? I'm not arguing (for once)...just trying to learn :)
  17. Chris75

    Chris75 Electrician

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    608
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    if you take a look at 314.16 (B)(4) Device or Equipment Fill

    For each yoke or strap containing one or more devices or equipment, a double volume allowance in accordance with Table 314.16(B) shall be made for each yoke or strap based on the largest conductor connected to a device(s) or equipment supported by that yoke or strap.
  18. jwelectric

    jwelectric Electrical Contractor/Instructor

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    Didn't mean to sound harsh I meant it to sound funny.

    Looking for one of those 1 1/2 inch deep go to Lowe's Home Improvement on highway 64/49 Asheboro, North Carolina and they have them by the case.
  19. Lakee911

    Lakee911 I&C Engineer (mostly WWTP)

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    We got a winner!

    Ok then. Ha ha :)

    Ok, so I went to bLowes, in Columbus, OH and I measured these boxes. Unfortunately, these are measured 1.5" deep from the inside and once you add the back and the plaster ring they are approximately 1-11/16 deep. Boo

    So, I thought that another option would be to use a plastic 4"x4" box and sand or cut 3/16" of an inch off the face to make up for the added height. This would doable, but not ideal for more than a box or two.

    I did, however, stumble upon this Raco box (http://www.myproship.com/index.aspx...38bfb9907b33d920d4&tab=13&Qtype=1&sku=6228373) at Lowes. It is exactly 1.5" inches deep, on the outside, and it is gangable, if that is the correct term. A screw comes off the side and the side comes off. Multiple boxes can then be attached to eachother. You can put as many together as you would like. The plaster ears come off too to make a standard box. They're $1.98 each.

    So, ok I'm good. I'm done. Thanks! :)
  20. Lakee911

    Lakee911 I&C Engineer (mostly WWTP)

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    I'm not sure I understand that, but my code book is at work. I'll look at it tomorrow. Is that 2008 or 2005?

    Jason

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