Ribbed metal rough in

[fireryan]

What's the best way to rough in boxes behind ribbed metal walls. Has to be in conduit or flex, is the best way to leave the flex a little long and just adjust the boxes as they are putting up the tin so you don't line up on a rib?

 

[electrofelon]

What's the best way to rough in boxes behind ribbed metal walls. Has to be in conduit or flex, is the best way to leave the flex a little long and just adjust the boxes as they are putting up the tin so you don't line up on a rib?

I would leave a wire behind and drill out the metal for a box after the metal is installed. I would also put up some blocking so I had something to secure the box to.

Is this like a steel building or traditional wood framing with metal siding?

 

[fireryan]

I would leave a wire behind and drill out the metal for a box after the metal is installed. I would also put up some blocking so I had something to secure the box to.

Is this like a steel building or traditional wood framing with metal siding?

Wood frame building. Specs require the boxes to be recessed in the walls unfortunently

 

[electrofelon]

Wood frame building. Specs require the boxes to be recessed in the walls unfortunently

I would mark out the locations, put a block in to fasten an octagon box to and leave a wire there. Drill the hole after the metal is up, Mount the box.

Another option might be able to use a bar hanger box and leave it loose so you can slide it left or right. You would have to get your height near perfect though.

 

[readydave8]

Vinyl siding blocks?

 

[electrofelon]

Vinyl siding blocks?

Yeah might be a good idea. Or perhaps could have the carpenters make you some out of cedar. depends on the profile of the metal. I was assuming with my comments that there was a flat spot large enough for the fixture canopy, maybe that's not the case.

 

[Little Bill]

I would mark out the locations, put a block in to fasten an octagon box to and leave a wire there.

I believe the OP is talking about receptacle boxes, not ceiling boxes.

 

[electrofelon]

I believe the OP is talking about receptacle boxes, not ceiling boxes.

Yeah could be, don't know why I assumed fixture boxes. If for outlets, and assuming this is outside I would probably use an Arlington inbox.

 

[Little Bill]

Yeah could be, don't know why I assumed fixture boxes. If for outlets, and assuming this is outside I would probably use an Arlington inbox.

I don't think he means outside either. I think it is a metal building with corrugated steel. He is roughing it in and the receptacles are to be recessed. He wants to know how to avoid the ribs in the steel when putting in the boxes. IMO, he is going to have to work with the installer of the metal siding. May have to put in some blocking to mount the receptacle boxes to. Or maybe some Caddy mounts for the boxes.