Firewall and electrical switch

[Cecil]

My garage attaches to my house.  Therefore, there is a 5/8" drywall requirement on the wall between the garage and the house.  I want to add a light switch to that wall.  Does it need to be on the surface, or can I recess it in the drywall like is normally done inside the house?  Thanks.

[Robert Adams]

My garage attaches to my house.  Therefore, there is a 5/8" drywall requirement on the wall between the garage and the house.  I want to add a light switch to that wall.  Does it need to be on the surface, or can I recess it in the drywall like is normally done inside the house?  Thanks.

No different than any other switch. Cut a hole pop in a box and wire it up.

[K. L. McReynolds]

If you use a box, you can either set it so the outer edge of the box is 1/2" recessed from the surface so the switch toggle extends properly. Otherwise the toggle will be recessed in relation to the switch plate.

[Snipe Hunter]

It needs to be attached to a stud (can't use the retrofit boxes with drywall clips) and there can't be another box on the other side of the wall in the same stud bay without using some sort of fire-stop material in the box. Google... 2012 IBC Section 714 Penetrations boxes in walls 714.3

[FS7]

It needs to be attached to a stud (can't use the retrofit boxes with drywall clips) and there can't be another box on the other side of the wall in the same stud bay without using some sort of fire-stop material in the box. Google... 2012 IBC Section 714 Penetrations  boxes in walls 714.3

I don't think the NEC mandates stud attachment, and even if it did there are old work boxes (Smart Boxes, I think) that have integral screws to allow for stud attachment. There are also heavier duty old work boxes that have the capability to support thicker walls (at least an inch) so that's not an issue either.

The second part is correct, though, and there shoudn't be a cutout on the other side for fire prevention purposes.

[Cecil]

It needs to be attached to a stud (can't use the retrofit boxes with drywall clips) and there can't be another box on the other side of the wall in the same stud bay without using some sort of fire-stop material in the box. Google... 2012 IBC Section 714 Penetrations  boxes in walls 714.3

Thanks.  It is the fire code I am concerned about, as you properly accessed.  There is a box on the other side of where I intended on putting it.  I will adjust to a different stud bay, perhaps the other side of the doorway.  Thanks.

[Snipe Hunter]

Thanks.  It is the fire code I am concerned about, as you properly accessed.  There is a box on the other side of where I intended on putting it.  I will adjust to a different stud bay, perhaps the other side of the doorway.  Thanks.

You could use this if you have access to the back of the boxes.

[MNice]

Depending on where you are located, the house/garage separation is usually not a true fire wall, but just 1 layer requirement on the garage side.  In MN, most houses are built to the IRC, not the IBC, and the requirement is 1/2" rock on the garage side, where a few years ago the requirement was 5/8" on the garage side.

[Cecil]

Depending on where you are located, the house/garage separation is usually not a true fire wall, but just 1 layer requirement on the garage side.  In MN, most houses are built to the IRC, not the IBC, and the requirement is 1/2" rock on the garage side, where a few years ago the requirement was 5/8" on the garage side.

You are correct, it is not a true fire wall.  Here the requirements are 5/8, but I believe both sides.

According to these folks (http://www.pennboc.org/files/other/14426..._walls.pdf)

There are five types of fire-resistance rated walls

Exterior walls (Section 705)
Fire walls (Section 706)
Fire barriers (Section 707)
Fire partitions (Section 708)
Smoke barriers (Section 709)

I believe this would be called a fire barrier.