Existing Walls

[Alwayslearningelec]

Any of you guys have tricks/tips when installing a 4" box in existing gypsum wall and have to support the box from stud to stud?

1. Would you cut the wall open vertical all the way to snake MC cable down if you have to feed from above?
2. Can you just get away with cutting the wall open from stud to stud where the box will go and be supported?

 

[LarryFine]

1. Would you cut the wall open vertical all the way to snake MC cable down if you have to feed from above?

Definitely not. I'm too good at fishing to do that. At most, I would make a small hole near the wall's top plate and either patch it or close it with a low-voltage ring and a blank plate.

2. Can you just get away with cutting the wall open from stud to stud where the box will go and be supported?

If it has to land on two studs, I would first try the expanding bar from a retro-fit ceiling fan box kit. You might have to drill mounting holes in the square box to match the round box.

 

[Alwayslearningelec]

Definitely not. I'm too good at fishing to do that. At most, I would make a small hole near the wall's top plate and either patch it or close it with a low-voltage ring and a blank plate.


If it has to land on two studs, I would first try the expanding bar from a retro-fit ceiling fan box kit. You might have to drill mounting holes in the square box to match the round box.

Thanks what if there is insulation within the walls that prevent fishing MC down?

 

[petersonra]

Thanks what if there is insulation within the walls that prevent fishing MC down?

What kind of insulation "prevents" fishing? Even foam can be fished around if you really want to. It is just time consuming and tedious.

 

[Alwayslearningelec]

What kind of insulation "prevents" fishing? Even foam can be fished around if you really want to. It is just time consuming and tedious.

So then maybe cutting the wall open would be quicker

 

[petersonra]

So then maybe cutting the wall open would be quicker

Depends on how hard it is to fix the drywall afterwards. Might be fairly straightforward to cut a section of drywall out floor to ceiling at the studs and just replace it and patch the cuts afterwards. But I would guess that drastic of a solution is not necessary.

Get with whomever is going to do the drywall and paint repairs and ask them. Maybe have them do the cutting too.

 

[Krusscher]

So then maybe cutting the wall open would be quicker

What kind of insulation is it? a fish rod or tape will go through fiberglass insulation.

Why does this box need to be supported by both studs?

 

[petersonra]

Why does this box need to be supported by both studs?

Probably wants to put it somewhere in the middle of the stud bay instead of at a stud.

Do you even need to support the box from a stud? Can't you use a metal old work box for this?

 

[roger]

Probably wants to put it somewhere in the middle of the stud bay instead of at a stud.

Do you even need to support the box from a stud? Can't you use a metal old work box for this?

If it's a fire rated partition it has to be secured to a stud per UL.

 

[ActionDave]

How much other drywall patching is involved in the project? A sixteen inch patch is not much worse than a four inch patch. If there is more tear out already going on and a crew coming to patch and paint I'd be inclined to make my job easier.

 

[roger]

How much other drywall patching is involved in the project? A sixteen inch patch is not much worse than a four inch patch. If there is more tear out already going on and a crew coming to patch and paint I'd be inclined to make my job easier.

When we had a few or more to do I would have a drywall company quote me for the number of repairs and include it in my price.

 

[LarryFine]

Thanks what if there is insulation within the walls that prevent fishing MC down?

It makes fising tougher, maybe, but it never prevents it, even with horizontal blocking.

A stud bay is three-dimensional, not two. There's against the drywall and away from it.