Extending existing wireways to make it larger

[Tainted]

If I have a 4"x4" metal wireway with wires already inside and I want to transform it into a 8"x8" wireway, is that possible?

What I mean is would it be possible to sawcut the 4"x4" wireway and just extend the wireway wall by adding some more metal onto it making it into a 8"x8" wireway?

would this be a violation

 

[infinity]

Metal wireways are designed to be cut, punched, modified, etc. How much modification eventually voids the listing is probably not defined and is an inspector's call. Are you asking about taking an 8x8 wireway and cutting it to modify the 4x4 wireway?

 

[Tainted]

Metal wireways are designed to be cut, punched, modified, etc. How much modification eventually voids the listing is probably not defined and is an inspector's call. Are you asking about taking an 8x8 wireway and cutting it to modify the 4x4 wireway?

not exactly what I'm saying,

There is a 4x4 existing wireway already installed in field with wires in it. We want to convert it into a 8x8 wireway without uninstalling and taking out wires inside the 4x4 wireway.

We propose to add extra metal onto the 4x4 wireway to transform it into a 8x8 wireway. This way, half of the wireway will be new metal horizontally if that makes sense.

 

[electrofelon]

FWIW, metal wireways are not required to be listed, but i bet most are. You are always at the mercy of the AHJ finding it acceptable per 110.2, 110.3

Not sure why this is in the code since they are not required to be listed, but it says what it says so make sure you dont cut off the part that has the label...

376.120 Marking. Metal wireways shall be so marked that their manufacturer’s name or trademark will be visible after installation.

 

[Tainted]

FWIW, metal wireways are not required to be listed, but i bet most are. You are always at the mercy of the AHJ finding it acceptable per 110.2, 110.3

Not sure why this is in the code since they are not required to be listed, but it says what it says so make sure you dont cut off the part that has the label...

376.120 Marking. Metal wireways shall be so marked that their manufacturer’s name or trademark will be visible after installation.

Interesting point about the marking.

So in my situation the wireway is going to be half manufactured by me because I'm modifying the existing 4x4 wireway into a 8x8 wireway lol. All I'm doing is adding new sheet metal onto it . Yea it's strange how this is in the code

 

[LarryFine]

Wouldn't it be 1/4 existing and 3/4 new in cross-section?

 

[Tainted]

Wouldn't it be 1/4 existing and 3/4 new in cross-section?

You are correct, i screwed up the math

 

[electrofelon]

In practice, I would say if the work is done well and looks neat and clean in the end, the inspector probably will never notice

 

[Tainted]

In practice, I would say if the work is done well and looks neat and clean in the end, the inspector probably will never notice

Instead of modifying the 4x4 wireway, I think it would be easier if I cut the 4x4 out of the way and get one of the 8x8 wireways with hinged cover and just tug all the existing wires in there.

 

[LarryFine]

So, you want to keep the back and either the top or the bottom, so you'd have to cut away the bottom or top you want to remove, as well as the front lip of the remaining horizontal surface.

Then you have to remove 4" of what will be the back and 4" of the horizontal surface of the new wireway you want to join into the old one. Then you need to weld or splice them together.

 

[Tainted]

So, you want to keep the back and either the top or the bottom, so you'd have to cut away the bottom or top you want to remove, as well as the front lip of the remaining horizontal surface.

Then you have to remove 4" of what will be the back and 4" of the horizontal surface of the new wireway you want to join into the old one. Then you need to weld or splice them together.

it will involve welding or screwing it in with bolts. but honestly this is way to much work and is more complicated than just getting a 8x8 wireway with hinged covers see post 9

 

[don_resqcapt19]

What type of circuits are in the wireway? Will there be an issue with ampacity adjustment because there are more than 30 current carrying conductors in the 8x8 wireway?

 

[petersonra]

Could you install the 4x4 inside the 8x8? No mods to the smaller one required that way.

 

[PaulMmn]

Instead of modifying the 4x4 wireway, I think it would be easier if I cut the 4x4 out of the way and get one of the 8x8 wireways with hinged cover and just tug all the existing wires in there.

View attachment 2572550

What is the construction of the existing 4x4? Same thing, with a removable cover? A couple of straps to hang the contents during the conversion, remove the old, position the new, and undo the straps.

 

[wwhitney]

There are still the conductor entries and exits from the wireway to deal with--those are presumably not through the hinged cover, but rather through an end plate, or through one of the other 3 sidewalls of the wireway.

So to do the changeover without disconnecting conductors, you'd need to cut out part of the existing wireway around each conductor entry/exit, a piece large enough to reach a free edge of the wireway. Then you can remove the remaining wireway and endwalls, leaving those pieces around the conductors.

For the new wireway, you'd need to cut out corresponding pieces in the desired locations, again with each cutout extending to a free edge of one of the new pieces. Perhaps otherwise making the cutouts smaller, so each piece of the old wireway would overlap the new wireway so that you could attach the old pieces to the new wireway.

Cheers, Wayne

 

[Tainted]

What type of circuits are in the wireway? Will there be an issue with ampacity adjustment because there are more than 30 current carrying conductors in the 8x8 wireway?

apartment feeders, no more than 30 CCC.

Could you install the 4x4 inside the 8x8? No mods to the smaller one required that way.

I probably could, and then I could put 30 CCC in the area outside of the 4x4 since the existing will have barriers