stuffing electrical boxes

Discussion in 'Misc DIY' started by James Owens, Oct 4, 2004.

  1. James Owens

    James Owens Guest

    Is there a trick to stuffing the caps and wires into an electrical box? So
    far I've done a few outlets with junctions (3 x 2 x 2.5 box, one 14-2
    cable in, one 14-2 out, 3 caps, 1 one-inch duplex outlet with pigtails)
    and my fingers hurt.

    I've left seven or eight inches of free cable inside each box (six is the
    required minimum but the guide says to go with eight if possible) and the
    pigtails are about three inches, and I'm using Marette 331 caps (not so
    big). I've tried folding the wires accordion-style in advance of
    connecting the outlet and that helps a little, but I still feel like I'm
    cramming the stuff in.

    Also, I keep thinking the inspector will come in and say, "Why did you
    connect this outlet to that circuit? You should have run them this way
    instead." It's not a bad layout (I used to design printed circuit boards
    for a living) but I could have used shorter runs if I hadn't been
    particular about serving each corner of the space (two rooms in a 26 x 10'
    area) with each of two circuits. As long as I have a fair distribution in
    each room and observe the technical requirements, does the inspector care
    which circuit goes where?

    I think I'm suffering from Inspector Anxiety.



    --
    "For it is only of the new one grows tired. Of the old one never tires."
    -- Kierkegaard, _Repetition_

    James Owens, Ottawa, Canada
     
    James Owens, Oct 4, 2004
    #1
    1. Advertising

  2. You should have consulted article 314 of the National Electrical Code prior
    to the installation of your outlet boxes. By code definition they are too
    small. Table 314.16(A) tells you that you are allowed six number 14
    conductors in the box. However you must deduct two from that total for each
    wiring device (Outlet) in that box and also deduct one wire for an internal
    wire clamp. If you used a connector that has its clamping mechanism outside
    of the box (Such as a romex connector) then no deduction for a clamp is
    necessary. Fortunately the ground wire only counts as one regardless of the
    amount. The pigtails don't count, but they sure do add to the space.

    You should have used 3.5" deep boxes which is permitted to have nine number
    14 wires. You wouldn't have had any problem "Stuffing" the wires, pigtails,
    and outlets into deeper boxes and you would have been code compliant. If
    depth was a concern, you could have used 4" x 4" x 1.5" square boxes with
    plaster rings based on the depth of your finished wall.

    Plastic outlet boxes tend to have more volume than the metal outlet boxes.
    They usually have the cubic inch volume stamped on them.

    I don't know what guide you used, but you should have picked up a copy of
    the National Electrical Code (NFPA 70) also. You can get it on Amazon.


    John Grabowski
    http://www.mrelectrician.tv




    "James Owens" <> wrote in message
    news:cjr2gj$418$...
    >
    > Is there a trick to stuffing the caps and wires into an electrical box? So
    > far I've done a few outlets with junctions (3 x 2 x 2.5 box, one 14-2
    > cable in, one 14-2 out, 3 caps, 1 one-inch duplex outlet with pigtails)
    > and my fingers hurt.
    >
    > I've left seven or eight inches of free cable inside each box (six is the
    > required minimum but the guide says to go with eight if possible) and the
    > pigtails are about three inches, and I'm using Marette 331 caps (not so
    > big). I've tried folding the wires accordion-style in advance of
    > connecting the outlet and that helps a little, but I still feel like I'm
    > cramming the stuff in.
    >
    > Also, I keep thinking the inspector will come in and say, "Why did you
    > connect this outlet to that circuit? You should have run them this way
    > instead." It's not a bad layout (I used to design printed circuit boards
    > for a living) but I could have used shorter runs if I hadn't been
    > particular about serving each corner of the space (two rooms in a 26 x 10'
    > area) with each of two circuits. As long as I have a fair distribution in
    > each room and observe the technical requirements, does the inspector care
    > which circuit goes where?
    >
    > I think I'm suffering from Inspector Anxiety.
    >
    >
    >
    > --
    > "For it is only of the new one grows tired. Of the old one never tires."
    > -- Kierkegaard, _Repetition_
    >
    > James Owens, Ottawa, Canada
     
    John Grabowski, Oct 4, 2004
    #2
    1. Advertising

  3. James Owens

    Dave Guest

    John, by my code book (Canada), he is allowed four conductors and four
    nuts, and he meets that. The code book I use accounts for the internal
    clamps and the duplex receptacle already.
    Are you using pigtails on the ground as well? If so, and if this is a
    duplex plug, you could leave one of the romex ground wires long, wrap it
    around a box ground screw, and then attach the distal end to the ground
    screw on the plug. The other ground wire can wrap around another ground
    screw on the box so you don't need the ground pigtail. Just be sure you have
    only one wire wrapped around one screw, as 'doubling up' on a screw is a
    no-no.. Electricians in my country do this all the time, and you would only
    need two nuts to fill the box.
    Get used to the sore fingers, it's the price you pay to enjoy manual
    labour.
    Just to clarify, I am not an electrician and do not know all the details
    of US code.

    Dave

    "John Grabowski" <> wrote in message
    news:5jb8d.5110$g%...
    > You should have consulted article 314 of the National Electrical Code
    > prior
    > to the installation of your outlet boxes. By code definition they are too
    > small. Table 314.16(A) tells you that you are allowed six number 14
    > conductors in the box. However you must deduct two from that total for
    > each
    > wiring device (Outlet) in that box and also deduct one wire for an
    > internal
    > wire clamp. If you used a connector that has its clamping mechanism
    > outside
    > of the box (Such as a romex connector) then no deduction for a clamp is
    > necessary. Fortunately the ground wire only counts as one regardless of
    > the
    > amount. The pigtails don't count, but they sure do add to the space.
    >
    > You should have used 3.5" deep boxes which is permitted to have nine
    > number
    > 14 wires. You wouldn't have had any problem "Stuffing" the wires,
    > pigtails,
    > and outlets into deeper boxes and you would have been code compliant. If
    > depth was a concern, you could have used 4" x 4" x 1.5" square boxes with
    > plaster rings based on the depth of your finished wall.
    >
    > Plastic outlet boxes tend to have more volume than the metal outlet boxes.
    > They usually have the cubic inch volume stamped on them.
    >
    > I don't know what guide you used, but you should have picked up a copy of
    > the National Electrical Code (NFPA 70) also. You can get it on Amazon.
    >
    >
    > John Grabowski
    > http://www.mrelectrician.tv
    >
    >
    >
    >
    > "James Owens" <> wrote in message
    > news:cjr2gj$418$...
    >>
    >> Is there a trick to stuffing the caps and wires into an electrical box?
    >> So
    >> far I've done a few outlets with junctions (3 x 2 x 2.5 box, one 14-2
    >> cable in, one 14-2 out, 3 caps, 1 one-inch duplex outlet with pigtails)
    >> and my fingers hurt.
    >>
    >> I've left seven or eight inches of free cable inside each box (six is the
    >> required minimum but the guide says to go with eight if possible) and the
    >> pigtails are about three inches, and I'm using Marette 331 caps (not so
    >> big). I've tried folding the wires accordion-style in advance of
    >> connecting the outlet and that helps a little, but I still feel like I'm
    >> cramming the stuff in.
    >>
    >> Also, I keep thinking the inspector will come in and say, "Why did you
    >> connect this outlet to that circuit? You should have run them this way
    >> instead." It's not a bad layout (I used to design printed circuit boards
    >> for a living) but I could have used shorter runs if I hadn't been
    >> particular about serving each corner of the space (two rooms in a 26 x
    >> 10'
    >> area) with each of two circuits. As long as I have a fair distribution in
    >> each room and observe the technical requirements, does the inspector care
    >> which circuit goes where?
    >>
    >> I think I'm suffering from Inspector Anxiety.
    >>
    >>
    >>
    >> --
    >> "For it is only of the new one grows tired. Of the old one never tires."
    >> -- Kierkegaard, _Repetition_
    >>
    >> James Owens, Ottawa, Canada

    >
    >
     
    Dave, Oct 4, 2004
    #3
  4. James Owens

    James Owens Guest

    Thanks. I'm working to Ontario code and I have carefully read a simplified
    guide, last updated 2003, with box fill tables that let me do this.
    There's even an illustration that shows basically the boxes I'm stuffing,
    and it says to use 2 x 3 x 2.5 for the job. In my several trips to Rona
    (the Canadian equivalent of Home Depot) I have never even seen a box 3.5"
    deep. (I did pick up some 3" deep boxes for junctions containing a
    switch.)

    Running a cable into and out of a box with a receptacle in it has got to be
    a fairly routine thing -- practically unavoidable. You don't mean they require
    3.5 deep boxes in the States? (If so, they must be easier to stuff!)

    BTW, in the Ontario code, the bonding wires don't count in the box fill
    calculations. For those purposes I have only four wires. The loomex cable
    clamps are built into the box, at the back.



    "John Grabowski" () writes:
    > You should have consulted article 314 of the National Electrical Code prior
    > to the installation of your outlet boxes. By code definition they are too
    > small. Table 314.16(A) tells you that you are allowed six number 14
    > conductors in the box. However you must deduct two from that total for each
    > wiring device (Outlet) in that box and also deduct one wire for an internal
    > wire clamp. If you used a connector that has its clamping mechanism outside
    > of the box (Such as a romex connector) then no deduction for a clamp is
    > necessary. Fortunately the ground wire only counts as one regardless of the
    > amount. The pigtails don't count, but they sure do add to the space.
    >
    > You should have used 3.5" deep boxes which is permitted to have nine number
    > 14 wires. You wouldn't have had any problem "Stuffing" the wires, pigtails,
    > and outlets into deeper boxes and you would have been code compliant. If
    > depth was a concern, you could have used 4" x 4" x 1.5" square boxes with
    > plaster rings based on the depth of your finished wall.
    >
    > Plastic outlet boxes tend to have more volume than the metal outlet boxes.
    > They usually have the cubic inch volume stamped on them.
    >
    > I don't know what guide you used, but you should have picked up a copy of
    > the National Electrical Code (NFPA 70) also. You can get it on Amazon.
    >
    >
    > John Grabowski
    > http://www.mrelectrician.tv
    >
    >
    >
    >
    > "James Owens" <> wrote in message
    > news:cjr2gj$418$...
    >>
    >> Is there a trick to stuffing the caps and wires into an electrical box? So
    >> far I've done a few outlets with junctions (3 x 2 x 2.5 box, one 14-2
    >> cable in, one 14-2 out, 3 caps, 1 one-inch duplex outlet with pigtails)
    >> and my fingers hurt.
    >>
    >> I've left seven or eight inches of free cable inside each box (six is the
    >> required minimum but the guide says to go with eight if possible) and the
    >> pigtails are about three inches, and I'm using Marette 331 caps (not so
    >> big). I've tried folding the wires accordion-style in advance of
    >> connecting the outlet and that helps a little, but I still feel like I'm
    >> cramming the stuff in.
    >>
    >> Also, I keep thinking the inspector will come in and say, "Why did you
    >> connect this outlet to that circuit? You should have run them this way
    >> instead." It's not a bad layout (I used to design printed circuit boards
    >> for a living) but I could have used shorter runs if I hadn't been
    >> particular about serving each corner of the space (two rooms in a 26 x 10'
    >> area) with each of two circuits. As long as I have a fair distribution in
    >> each room and observe the technical requirements, does the inspector care
    >> which circuit goes where?
    >>
    >> I think I'm suffering from Inspector Anxiety.
    >>
    >>
    >>
    >> --
    >> "For it is only of the new one grows tired. Of the old one never tires."
    >> -- Kierkegaard, _Repetition_
    >>
    >> James Owens, Ottawa, Canada

    >
    >



    --
    "For it is only of the new one grows tired. Of the old one never tires."
    -- Kierkegaard, _Repetition_

    James Owens, Ottawa, Canada
     
    James Owens, Oct 4, 2004
    #4
  5. James Owens

    James Owens Guest

    "Dave" () writes:

    > Are you using pigtails on the ground as well? If so, and if this is a
    > duplex plug, you could leave one of the romex ground wires long, wrap it
    > around a box ground screw, and then attach the distal end to the ground
    > screw on the plug. The other ground wire can wrap around another ground
    > screw on the box so you don't need the ground pigtail. Just be sure you have
    > only one wire wrapped around one screw, as 'doubling up' on a screw is a
    > no-no.. Electricians in my country do this all the time, and you would only
    > need two nuts to fill the box.


    Thanks. I'm using a pigtail for the ground. The book I'm working from is
    explicit: the bonding wire goes first to the box, next to all the other
    bare wires, third via pigtail to the receptacle. So that's the way I'll do
    it -- just call me chicken. :)

    It isn't explicit about whether, if there are two bare wires coming in,
    only one of them should go to the box. The text doesn't say, but the
    picture shows it that way. I've taken the incoming cable (from source) to
    the box, but there are two screws -- I could connect the other bare
    wire to the box before the pigtail. Would that be a good idea or not?

    Also, about "wrapping around" the screw, is a complete 360 needed, or a
    270, or is it OK just to run the wire under the screw at one side?


    > Get used to the sore fingers, it's the price you pay to enjoy manual
    > labour.


    I was afraid of that. Thanks.

    --
    "For it is only of the new one grows tired. Of the old one never tires."
    -- Kierkegaard, _Repetition_

    James Owens, Ottawa, Canada
     
    James Owens, Oct 4, 2004
    #5
  6. James Owens

    Eric Tonks Guest

    A 3 1/2" deep box would be difficult to use on 3 1/2" deep 2" x 4"s,
    especially with ground screws and clamp screws sticking out the back. That
    means the drywall would be hitting, and pressing on the back and could cause
    the screws to pop a hole through the drywall. They would be fine for 2" x 6"
    studs.


    "James Owens" <> wrote in message
    news:cjrksm$q0p$...
    >
    > Thanks. I'm working to Ontario code and I have carefully read a simplified
    > guide, last updated 2003, with box fill tables that let me do this.
    > There's even an illustration that shows basically the boxes I'm stuffing,
    > and it says to use 2 x 3 x 2.5 for the job. In my several trips to Rona
    > (the Canadian equivalent of Home Depot) I have never even seen a box 3.5"
    > deep. (I did pick up some 3" deep boxes for junctions containing a
    > switch.)
    >
    > Running a cable into and out of a box with a receptacle in it has got to

    be
    > a fairly routine thing -- practically unavoidable. You don't mean they

    require
    > 3.5 deep boxes in the States? (If so, they must be easier to stuff!)
    >
    > BTW, in the Ontario code, the bonding wires don't count in the box fill
    > calculations. For those purposes I have only four wires. The loomex cable
    > clamps are built into the box, at the back.
    >
    >
    >
    > "John Grabowski" () writes:
    > > You should have consulted article 314 of the National Electrical Code

    prior
    > > to the installation of your outlet boxes. By code definition they are

    too
    > > small. Table 314.16(A) tells you that you are allowed six number 14
    > > conductors in the box. However you must deduct two from that total for

    each
    > > wiring device (Outlet) in that box and also deduct one wire for an

    internal
    > > wire clamp. If you used a connector that has its clamping mechanism

    outside
    > > of the box (Such as a romex connector) then no deduction for a clamp is
    > > necessary. Fortunately the ground wire only counts as one regardless of

    the
    > > amount. The pigtails don't count, but they sure do add to the space.
    > >
    > > You should have used 3.5" deep boxes which is permitted to have nine

    number
    > > 14 wires. You wouldn't have had any problem "Stuffing" the wires,

    pigtails,
    > > and outlets into deeper boxes and you would have been code compliant.

    If
    > > depth was a concern, you could have used 4" x 4" x 1.5" square boxes

    with
    > > plaster rings based on the depth of your finished wall.
    > >
    > > Plastic outlet boxes tend to have more volume than the metal outlet

    boxes.
    > > They usually have the cubic inch volume stamped on them.
    > >
    > > I don't know what guide you used, but you should have picked up a copy

    of
    > > the National Electrical Code (NFPA 70) also. You can get it on Amazon.
    > >
    > >
    > > John Grabowski
    > > http://www.mrelectrician.tv
    > >
    > >
    > >
    > >
    > > "James Owens" <> wrote in message
    > > news:cjr2gj$418$...
    > >>
    > >> Is there a trick to stuffing the caps and wires into an electrical box?

    So
    > >> far I've done a few outlets with junctions (3 x 2 x 2.5 box, one 14-2
    > >> cable in, one 14-2 out, 3 caps, 1 one-inch duplex outlet with pigtails)
    > >> and my fingers hurt.
    > >>
    > >> I've left seven or eight inches of free cable inside each box (six is

    the
    > >> required minimum but the guide says to go with eight if possible) and

    the
    > >> pigtails are about three inches, and I'm using Marette 331 caps (not so
    > >> big). I've tried folding the wires accordion-style in advance of
    > >> connecting the outlet and that helps a little, but I still feel like

    I'm
    > >> cramming the stuff in.
    > >>
    > >> Also, I keep thinking the inspector will come in and say, "Why did you
    > >> connect this outlet to that circuit? You should have run them this way
    > >> instead." It's not a bad layout (I used to design printed circuit

    boards
    > >> for a living) but I could have used shorter runs if I hadn't been
    > >> particular about serving each corner of the space (two rooms in a 26 x

    10'
    > >> area) with each of two circuits. As long as I have a fair distribution

    in
    > >> each room and observe the technical requirements, does the inspector

    care
    > >> which circuit goes where?
    > >>
    > >> I think I'm suffering from Inspector Anxiety.
    > >>
    > >>
    > >>
    > >> --
    > >> "For it is only of the new one grows tired. Of the old one never

    tires."
    > >> -- Kierkegaard, _Repetition_
    > >>
    > >> James Owens, Ottawa, Canada

    > >
    > >

    >
    >
    > --
    > "For it is only of the new one grows tired. Of the old one never tires."
    > -- Kierkegaard, _Repetition_
    >
    > James Owens, Ottawa, Canada
     
    Eric Tonks, Oct 4, 2004
    #6
  7. James Owens

    zxcvbob Guest

    James Owens wrote:
    > "Dave" () writes:
    >
    >
    >> Are you using pigtails on the ground as well? If so, and if this is a
    >>duplex plug, you could leave one of the romex ground wires long, wrap it
    >>around a box ground screw, and then attach the distal end to the ground
    >>screw on the plug. The other ground wire can wrap around another ground
    >>screw on the box so you don't need the ground pigtail. Just be sure you have
    >>only one wire wrapped around one screw, as 'doubling up' on a screw is a
    >>no-no.. Electricians in my country do this all the time, and you would only
    >>need two nuts to fill the box.

    >
    >
    > Thanks. I'm using a pigtail for the ground. The book I'm working from is
    > explicit: the bonding wire goes first to the box, next to all the other
    > bare wires, third via pigtail to the receptacle. So that's the way I'll do
    > it -- just call me chicken. :)


    If you don't have many to do, you might look for some ready-made
    pigtails made with stranded wire.

    > It isn't explicit about whether, if there are two bare wires coming in,
    > only one of them should go to the box. The text doesn't say, but the
    > picture shows it that way. I've taken the incoming cable (from source) to
    > the box, but there are two screws -- I could connect the other bare
    > wire to the box before the pigtail. Would that be a good idea or not?
    > Also, about "wrapping around" the screw, is a complete 360 needed, or a
    > 270, or is it OK just to run the wire under the screw at one side?


    Wrap it around as much as you can without it overlapping itself. I
    generally go 270 if the wire stops at the screw, or 180 - 200 if the
    wire is wrapping around the screw and then continuing on to the device.


    BTW, your 2x3x2.5" box should be fine for two #14 cables and a device.
    It's marginal (and probably too small) for two #12 cables and a device.

    Bob
     
    zxcvbob, Oct 4, 2004
    #7
  8. James Owens

    willshak Guest

    Eric Tonks wrote:

    >A 3 1/2" deep box would be difficult to use on 3 1/2" deep 2" x 4"s,
    >especially with ground screws and clamp screws sticking out the back. That
    >means the drywall would be hitting, and pressing on the back and could cause
    >the screws to pop a hole through the drywall. They would be fine for 2" x 6"
    >studs.
    >
    >

    Nope, the box usually projects out from the front of the stud a distance
    equal to the thickness of the drywall installed, or to be installed,
    usually 1/2". Therefore there is a 1/2" gap between the back of the box
    and the opposite side drywall.

    >
    >"James Owens" <> wrote in message
    >news:cjrksm$q0p$...
    >
    >
    >>Thanks. I'm working to Ontario code and I have carefully read a simplified
    >>guide, last updated 2003, with box fill tables that let me do this.
    >>There's even an illustration that shows basically the boxes I'm stuffing,
    >>and it says to use 2 x 3 x 2.5 for the job. In my several trips to Rona
    >>(the Canadian equivalent of Home Depot) I have never even seen a box 3.5"
    >>deep. (I did pick up some 3" deep boxes for junctions containing a
    >>switch.)
    >>
    >>Running a cable into and out of a box with a receptacle in it has got to
    >>
    >>

    >be
    >
    >
    >>a fairly routine thing -- practically unavoidable. You don't mean they
    >>
    >>

    >require
    >
    >
    >>3.5 deep boxes in the States? (If so, they must be easier to stuff!)
    >>
    >>BTW, in the Ontario code, the bonding wires don't count in the box fill
    >>calculations. For those purposes I have only four wires. The loomex cable
    >>clamps are built into the box, at the back.
    >>
    >>
    >>
    >>"John Grabowski" () writes:
    >>
    >>
    >>>You should have consulted article 314 of the National Electrical Code
    >>>
    >>>

    >prior
    >
    >
    >>>to the installation of your outlet boxes. By code definition they are
    >>>
    >>>

    >too
    >
    >
    >>>small. Table 314.16(A) tells you that you are allowed six number 14
    >>>conductors in the box. However you must deduct two from that total for
    >>>
    >>>

    >each
    >
    >
    >>>wiring device (Outlet) in that box and also deduct one wire for an
    >>>
    >>>

    >internal
    >
    >
    >>>wire clamp. If you used a connector that has its clamping mechanism
    >>>
    >>>

    >outside
    >
    >
    >>>of the box (Such as a romex connector) then no deduction for a clamp is
    >>>necessary. Fortunately the ground wire only counts as one regardless of
    >>>
    >>>

    >the
    >
    >
    >>>amount. The pigtails don't count, but they sure do add to the space.
    >>>
    >>>You should have used 3.5" deep boxes which is permitted to have nine
    >>>
    >>>

    >number
    >
    >
    >>>14 wires. You wouldn't have had any problem "Stuffing" the wires,
    >>>
    >>>

    >pigtails,
    >
    >
    >>>and outlets into deeper boxes and you would have been code compliant.
    >>>
    >>>

    >If
    >
    >
    >>>depth was a concern, you could have used 4" x 4" x 1.5" square boxes
    >>>
    >>>

    >with
    >
    >
    >>>plaster rings based on the depth of your finished wall.
    >>>
    >>>Plastic outlet boxes tend to have more volume than the metal outlet
    >>>
    >>>

    >boxes.
    >
    >
    >>>They usually have the cubic inch volume stamped on them.
    >>>
    >>>I don't know what guide you used, but you should have picked up a copy
    >>>
    >>>

    >of
    >
    >
    >>>the National Electrical Code (NFPA 70) also. You can get it on Amazon.
    >>>
    >>>
    >>>John Grabowski
    >>>http://www.mrelectrician.tv
    >>>
    >>>
    >>>
    >>>
    >>>"James Owens" <> wrote in message
    >>>news:cjr2gj$418$...
    >>>
    >>>
    >>>>Is there a trick to stuffing the caps and wires into an electrical box?
    >>>>
    >>>>

    >So
    >
    >
    >>>>far I've done a few outlets with junctions (3 x 2 x 2.5 box, one 14-2
    >>>>cable in, one 14-2 out, 3 caps, 1 one-inch duplex outlet with pigtails)
    >>>>and my fingers hurt.
    >>>>
    >>>>I've left seven or eight inches of free cable inside each box (six is
    >>>>
    >>>>

    >the
    >
    >
    >>>>required minimum but the guide says to go with eight if possible) and
    >>>>
    >>>>

    >the
    >
    >
    >>>>pigtails are about three inches, and I'm using Marette 331 caps (not so
    >>>>big). I've tried folding the wires accordion-style in advance of
    >>>>connecting the outlet and that helps a little, but I still feel like
    >>>>
    >>>>

    >I'm
    >
    >
    >>>>cramming the stuff in.
    >>>>
    >>>>Also, I keep thinking the inspector will come in and say, "Why did you
    >>>>connect this outlet to that circuit? You should have run them this way
    >>>>instead." It's not a bad layout (I used to design printed circuit
    >>>>
    >>>>

    >boards
    >
    >
    >>>>for a living) but I could have used shorter runs if I hadn't been
    >>>>particular about serving each corner of the space (two rooms in a 26 x
    >>>>
    >>>>

    >10'
    >
    >
    >>>>area) with each of two circuits. As long as I have a fair distribution
    >>>>
    >>>>

    >in
    >
    >
    >>>>each room and observe the technical requirements, does the inspector
    >>>>
    >>>>

    >care
    >
    >
    >>>>which circuit goes where?
    >>>>
    >>>>I think I'm suffering from Inspector Anxiety.
    >>>>
    >>>>
    >>>>
    >>>>--
    >>>>"For it is only of the new one grows tired. Of the old one never
    >>>>
    >>>>

    >tires."
    >
    >
    >>>>-- Kierkegaard, _Repetition_
    >>>>
    >>>> James Owens, Ottawa, Canada
    >>>>
    >>>>
    >>>
    >>>

    >>--
    >>"For it is only of the new one grows tired. Of the old one never tires."
    >>-- Kierkegaard, _Repetition_
    >>
    >> James Owens, Ottawa, Canada
    >>
    >>

    >
    >
    >
    >
     
    willshak, Oct 4, 2004
    #8
  9. James Owens

    Chris Lewis Guest

    According to James Owens <>:

    > Thanks. I'm working to Ontario code and I have carefully read a simplified
    > guide, last updated 2003, with box fill tables that let me do this.
    > There's even an illustration that shows basically the boxes I'm stuffing,
    > and it says to use 2 x 3 x 2.5 for the job. In my several trips to Rona
    > (the Canadian equivalent of Home Depot) I have never even seen a box 3.5"
    > deep. (I did pick up some 3" deep boxes for junctions containing a
    > switch.)


    It's best to always use the deep boxes (eg: 3") except when you simply
    don't have enough depth for it. Your fingers will thank you.
    --
    Chris Lewis, Una confibula non set est
    It's not just anyone who gets a Starship Cruiser class named after them.
     
    Chris Lewis, Oct 4, 2004
    #9
  10. James Owens

    willshak Guest

    willshak wrote:

    > Eric Tonks wrote:
    >
    >> A 3 1/2" deep box would be difficult to use on 3 1/2" deep 2" x 4"s,
    >> especially with ground screws and clamp screws sticking out the back.
    >> That
    >> means the drywall would be hitting, and pressing on the back and
    >> could cause
    >> the screws to pop a hole through the drywall. They would be fine for
    >> 2" x 6"
    >> studs.
    >>
    >>

    > Nope, the box usually projects out from the front of the stud a
    > distance equal to the thickness of the drywall installed, or to be
    > installed, usually 1/2". Therefore there is a 1/2" gap between the
    > back of the box and the opposite side drywall.



    I should have checked my shop first. Apparently, like lumber, they use
    nominal sizes for electrical boxes too. I have a 3" blue plastic box,
    that when measured is actually 2-7/8" from front to back (outside
    measurement). I also have a 3-1/2" (20 cu in) tan plastic, 2 hr fire
    rated box that when measured, is 3-1/4" from front to back (outside), so
    the gap between the back of a 3-1/2" box and the opposing drywall in a
    2x4 studded wall would be about 3/4", after allowing for the face
    drywall projection.
     
    willshak, Oct 4, 2004
    #10
  11. James Owens

    James Owens Guest

    Chris Lewis () writes:
    > According to James Owens <>:
    >
    >> Thanks. I'm working to Ontario code and I have carefully read a simplified
    >> guide, last updated 2003, with box fill tables that let me do this.
    >> There's even an illustration that shows basically the boxes I'm stuffing,
    >> and it says to use 2 x 3 x 2.5 for the job. In my several trips to Rona
    >> (the Canadian equivalent of Home Depot) I have never even seen a box 3.5"
    >> deep. (I did pick up some 3" deep boxes for junctions containing a
    >> switch.)

    >
    > It's best to always use the deep boxes (eg: 3") except when you simply
    > don't have enough depth for it. Your fingers will thank you.
    > --
    > Chris Lewis, Una confibula non set est
    > It's not just anyone who gets a Starship Cruiser class named after them.


    There's another puzzle for me. On an inside partition, The 3" box brings
    the incoming cable pretty close to the edge of the 3.5" stud -- closer
    than the 1.25 inch allowance, I believe. Where the cable is too close to
    the stud edge and not free to move aside, we're supposed to protect it
    against errant drywall screws using a metal plate attached to the stud.
    Would they be required behind the 3" box?

    No wonder people hire electricians to do this. . .



    --
    "For it is only of the new one grows tired. Of the old one never tires."
    -- Kierkegaard, _Repetition_

    James Owens, Ottawa, Canada
     
    James Owens, Oct 4, 2004
    #11
  12. James Owens

    NULL Guest

    KJS wrote:
    >
    > I am not familiar with the code used in Ontario. Under the NEC, you would
    > have to protect NM cable anywhere it was within 1 1/4" of the rough framing
    > surface even "behind" a box. (I assume you're concerned with the side of the
    > wall opposite to the box opening.)



    Is this really true that your have to protect the back of a 3" or 3.5"
    box for interior walls? I didn't see my builder do it 4 years ago when
    they built my house, that uses 2x4 studs. I don't think I see anyone do
    it .. I did not see anything like that at Home Depot.
     
    NULL, Oct 4, 2004
    #12
  13. James Owens

    James Owens Guest

    KJS () writes:

    > I am not familiar with the code used in Ontario. Under the NEC, you would
    > have to protect NM cable anywhere it was within 1 1/4" of the rough framing
    > surface even "behind" a box. (I assume you're concerned with the side of the
    > wall opposite to the box opening.)
    >
    > To return to your original question: I'm surprised the Ontario code allows
    > the box fill you're using. As another poster observed, it would not be
    > allowed under the NEC, and I was under the impression that Canadian codes
    > were generally more restrictive. More to the point: electrical codes are
    > minimal requirements for safety. They are not design manuals. I never use
    > single gang boxes (even the 2 1/2" deep ones) for duplex outlet
    > installations. They just don't have enough room for wire and device
    > installation. This is especially true with larger strap-mounted devices such
    > as GFCI receptacles.


    There are restrictions involving the receptacle size -- the tables I'm
    using assume are for receptacles or switches no deeper than one inch. For
    GFCI a bigger box would probably be required. Switches are a lot thinner
    than receptacles, but they're treated interchangeably.

    > There are requirements
    > for the minimum number of receptacles, however. Basically, there must be an
    > outlet for every 6 lineal feet of wall, with the outlets spaced as evenly as
    > possible. You might check your code for a similar requirement...
    >
    > Good Luck,
    >
    > - Kenneth


    The rule here is that any point on the wall has to be within six feet of a
    receptacle, measured along the wall (no cutting corners), with no
    obstacles (columns down to the floor, say). Also any isolated bit of wall
    longer than three feet has to have a receptacle. This is just for living
    spaces. The simplified code for kitchens takes up pages and pages. Thank
    goodness I don't need to know.

    BTW, our figures are really in centimeters, but we just ignore that.

    --
    "For it is only of the new one grows tired. Of the old one never tires."
    -- Kierkegaard, _Repetition_

    James Owens, Ottawa, Canada
     
    James Owens, Oct 4, 2004
    #13
  14. In article <>, KJS wrote:

    > By way of illustration, the NEC requires 2 cubic inches for each #14
    > conductor, with 1 conductor allowance for the aggregate of grounding
    > conductors, 2 allowances for each strap-mounted device (such as a duplex
    > receptacle), and 1 allowance for each internal cable clamp. Your application
    > therefore involves 9 conductor allowances for 18 cubic inches. A 3 x 2 x 2
    > 1/2 box is 12 1/2 cubic inches, while a 4 x 4 x 1 1/2 with 1/2" sindle device
    > ring totals 24 1/2 cubic inches.


    A couple questions on this:

    Does specifying the box size as 3 x 2 x 2.5 imply the box is metal?
    The OP spoke of grounding the box, so it is metal, I am just wondering
    about the terminology.

    Why is a 3 x 2 x 2.5 metal box only 12.5 cubic inches? 3*2*2.5 = 15.
    Is the volume loss due to slight undersizing, or rounding the corners,
    or what?

    In your conductor allowance, you made two allowances for clamps for
    the two cables. Do plastic romex clamps require an allowance? With
    metal clamps (two screws), can you put the clamp portion outside, and
    does that avoid an allowance?

    Thanks, Wayne
     
    Wayne Whitney, Oct 4, 2004
    #14
  15. I always use stranded wire because I don't have all these problems
    pushing the receptacle or switch back into the box. The only reason
    why Romex is even used is because it's slighly cheaper than stranded
    wire, and home buiulders are penny pinchers. Always buy the
    receptacle/switch box that you can put in a given location. My
    biggest gripe on boxes is that if you like the metal ones like I do (I
    would never use a plastic box) then it's either a "switch" box that
    isn't tall enough or a "handy" box that isn't deep enough. At least
    you get to pick which direction you want to be constricted in.
     
    Childfree Scott, Oct 4, 2004
    #15
  16. James Owens

    toller Guest

    Since no one else has mentioned this, maybe I am doing it wrong, but I never
    use 8". 4-6" depending on what I am doing.
     
    toller, Oct 4, 2004
    #16
  17. James Owens

    zxcvbob Guest

    Wayne Whitney wrote:

    > In article <>, KJS wrote:
    >
    >
    >>By way of illustration, the NEC requires 2 cubic inches for each #14
    >>conductor, with 1 conductor allowance for the aggregate of grounding
    >>conductors, 2 allowances for each strap-mounted device (such as a duplex
    >>receptacle), and 1 allowance for each internal cable clamp. Your application
    >>therefore involves 9 conductor allowances for 18 cubic inches. A 3 x 2 x 2
    >>1/2 box is 12 1/2 cubic inches, while a 4 x 4 x 1 1/2 with 1/2" sindle device
    >>ring totals 24 1/2 cubic inches.

    >
    >
    > A couple questions on this:
    >
    > Does specifying the box size as 3 x 2 x 2.5 imply the box is metal?
    > The OP spoke of grounding the box, so it is metal, I am just wondering
    > about the terminology.
    >
    > Why is a 3 x 2 x 2.5 metal box only 12.5 cubic inches? 3*2*2.5 = 15.
    > Is the volume loss due to slight undersizing, or rounding the corners,
    > or what?


    I assumed a 3*3*2.5" box would be about 14 in3, but I looked it up and
    surprise: <http://doityourself.com/store/outletboxes.htm> It is 12.5
    for almost all of them.

    > In your conductor allowance, you made two allowances for clamps for
    > the two cables. Do plastic romex clamps require an allowance? With
    > metal clamps (two screws), can you put the clamp portion outside, and
    > does that avoid an allowance?


    You can completely remove the bottom clamp from a switch box and have
    both cables come in from the top and save one allowance. I've never
    tried moving a clamp to the outside of the box...

    Bob
     
    zxcvbob, Oct 4, 2004
    #17
  18. James Owens

    KJS Guest

    On Mon, 4 Oct 2004 13:53:16 -0700, zxcvbob wrote
    (in article <>):

    > Wayne Whitney wrote:
    >
    >> In article <>, KJS
    >> wrote:
    >>
    >>
    >>> By way of illustration, the NEC requires 2 cubic inches for each #14
    >>> conductor, with 1 conductor allowance for the aggregate of grounding
    >>> conductors, 2 allowances for each strap-mounted device (such as a duplex
    >>> receptacle), and 1 allowance for each internal cable clamp. Your
    >>> application
    >>> therefore involves 9 conductor allowances for 18 cubic inches. A 3 x 2 x
    >>> 2
    >>> 1/2 box is 12 1/2 cubic inches, while a 4 x 4 x 1 1/2 with 1/2" sindle
    >>> device
    >>> ring totals 24 1/2 cubic inches.

    >>
    >>
    >> A couple questions on this:
    >>
    >> Does specifying the box size as 3 x 2 x 2.5 imply the box is metal?
    >> The OP spoke of grounding the box, so it is metal, I am just wondering
    >> about the terminology.
    >>
    >> Why is a 3 x 2 x 2.5 metal box only 12.5 cubic inches? 3*2*2.5 = 15.
    >> Is the volume loss due to slight undersizing, or rounding the corners,
    >> or what?

    >
    > I assumed a 3*3*2.5" box would be about 14 in3, but I looked it up and
    > surprise: <http://doityourself.com/store/outletboxes.htm> It is 12.5
    > for almost all of them.
    >
    >> In your conductor allowance, you made two allowances for clamps for
    >> the two cables. Do plastic romex clamps require an allowance? With
    >> metal clamps (two screws), can you put the clamp portion outside, and
    >> does that avoid an allowance?

    >
    > You can completely remove the bottom clamp from a switch box and have
    > both cables come in from the top and save one allowance. I've never
    > tried moving a clamp to the outside of the box...
    >
    > Bob


    Wayne & Bob -

    I was referring to metal boxes as covered by NEC 370-16. The table covers
    only certain common metal boxes. Other boxes (including plastic) must have
    their capacity indicated on them.

    The trade sizes of boxes are the exterior measurements, and the cubic inch
    capacity is taken from the interior measurements. The difference is wall
    thickness.

    The deduction for clamp fill applies to internal clamps only. Plastic or
    metal Romex clamps with an exterior clamping mechanism do not require a
    deduction. Not only can you install a "two-screw" metal Romex clamp with the
    mechanism outside the box, that's the way they're supposed to be installed!
    (The screws go outside and the locknut inside...)

    Regards,

    - Kenneth
     
    KJS, Oct 4, 2004
    #18
  19. James Owens

    KJS Guest

    On Mon, 4 Oct 2004 11:57:27 -0700, James Owens wrote
    (in article <cjs6en$ivj$>):

    >
    > KJS () writes:
    >
    >> I am not familiar with the code used in Ontario. Under the NEC, you would
    >> have to protect NM cable anywhere it was within 1 1/4" of the rough framing
    >> surface even "behind" a box. (I assume you're concerned with the side of
    >> the
    >> wall opposite to the box opening.)
    >>
    >> To return to your original question: I'm surprised the Ontario code allows
    >> the box fill you're using. As another poster observed, it would not be
    >> allowed under the NEC, and I was under the impression that Canadian codes
    >> were generally more restrictive. More to the point: electrical codes are
    >> minimal requirements for safety. They are not design manuals. I never use
    >> single gang boxes (even the 2 1/2" deep ones) for duplex outlet
    >> installations. They just don't have enough room for wire and device
    >> installation. This is especially true with larger strap-mounted devices
    >> such
    >> as GFCI receptacles.

    >
    > There are restrictions involving the receptacle size -- the tables I'm
    > using assume are for receptacles or switches no deeper than one inch. For
    > GFCI a bigger box would probably be required. Switches are a lot thinner
    > than receptacles, but they're treated interchangeably.
    >
    >> There are requirements
    >> for the minimum number of receptacles, however. Basically, there must be
    >> an
    >> outlet for every 6 lineal feet of wall, with the outlets spaced as evenly
    >> as
    >> possible. You might check your code for a similar requirement...
    >>
    >> Good Luck,
    >>
    >> - Kenneth

    >
    > The rule here is that any point on the wall has to be within six feet of a
    > receptacle, measured along the wall (no cutting corners), with no
    > obstacles (columns down to the floor, say). Also any isolated bit of wall
    > longer than three feet has to have a receptacle. This is just for living
    > spaces. The simplified code for kitchens takes up pages and pages. Thank
    > goodness I don't need to know.
    >
    > BTW, our figures are really in centimeters, but we just ignore that.
    >
    > --
    > "For it is only of the new one grows tired. Of the old one never tires."
    > -- Kierkegaard, _Repetition_
    >
    > James Owens, Ottawa, Canada


    James -

    Thanks for the info. Glad you were already up to speed on the required
    receptacle (sorry, I meant point) spacing.

    Regards,

    - Kenneth
     
    KJS, Oct 4, 2004
    #19
  20. James Owens

    zxcvbob Guest

    KJS wrote:
    > On Mon, 4 Oct 2004 13:53:16 -0700, zxcvbob wrote
    > (in article <>):
    >
    >
    >>Wayne Whitney wrote:
    >>
    >>
    >>>In article <>, KJS
    >>>wrote:
    >>>
    >>>
    >>>
    >>>>By way of illustration, the NEC requires 2 cubic inches for each #14
    >>>>conductor, with 1 conductor allowance for the aggregate of grounding
    >>>>conductors, 2 allowances for each strap-mounted device (such as a duplex
    >>>>receptacle), and 1 allowance for each internal cable clamp. Your
    >>>>application
    >>>>therefore involves 9 conductor allowances for 18 cubic inches. A 3 x 2 x
    >>>>2
    >>>>1/2 box is 12 1/2 cubic inches, while a 4 x 4 x 1 1/2 with 1/2" sindle
    >>>>device
    >>>>ring totals 24 1/2 cubic inches.
    >>>
    >>>
    >>>A couple questions on this:
    >>>
    >>>Does specifying the box size as 3 x 2 x 2.5 imply the box is metal?
    >>>The OP spoke of grounding the box, so it is metal, I am just wondering
    >>>about the terminology.
    >>>
    >>>Why is a 3 x 2 x 2.5 metal box only 12.5 cubic inches? 3*2*2.5 = 15.
    >>>Is the volume loss due to slight undersizing, or rounding the corners,
    >>>or what?

    >>
    >>I assumed a 3*3*2.5" box would be about 14 in3, but I looked it up and
    >>surprise: <http://doityourself.com/store/outletboxes.htm> It is 12.5
    >>for almost all of them.
    >>
    >>
    >>>In your conductor allowance, you made two allowances for clamps for
    >>>the two cables. Do plastic romex clamps require an allowance? With
    >>>metal clamps (two screws), can you put the clamp portion outside, and
    >>>does that avoid an allowance?

    >>
    >>You can completely remove the bottom clamp from a switch box and have
    >>both cables come in from the top and save one allowance. I've never
    >>tried moving a clamp to the outside of the box...
    >>
    >>Bob

    >
    >
    > Wayne & Bob -
    >
    > I was referring to metal boxes as covered by NEC 370-16. The table covers
    > only certain common metal boxes. Other boxes (including plastic) must have
    > their capacity indicated on them.
    >
    > The trade sizes of boxes are the exterior measurements, and the cubic inch
    > capacity is taken from the interior measurements. The difference is wall
    > thickness.
    >
    > The deduction for clamp fill applies to internal clamps only. Plastic or
    > metal Romex clamps with an exterior clamping mechanism do not require a
    > deduction. Not only can you install a "two-screw" metal Romex clamp with the
    > mechanism outside the box, that's the way they're supposed to be installed!
    > (The screws go outside and the locknut inside...)
    >
    > Regards,
    >
    > - Kenneth
    >



    The clamps I was talking about are inside the box and have one kind-of
    big screw. One clamp covers 2 holes, and there's one clamp at the top
    and one at the bottom of the box.

    Someone else asked about the integral clamps in plastic boxes (a little
    tab where you push through the cable.) I wouldn't count those at all,
    but I would make sure I wasn't already right at (or over) the number of
    conductors.

    Bob
     
    zxcvbob, Oct 4, 2004
    #20
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