Double Drywall Spacing for Electrical Boxes

redjr · « **on:** 16 Feb 2014, 01:41 am »

Hi all,

I'm getting a little further along on my basement build-out and have a question for anyone that has hung double 5/8" drywall and used Green Glue between the sheets. Reason I'm asking is I want to understand what the overall thickness of the drywall ends up being after Green Glue has been applied and setup properly. I'm sure that depends upon how much GG is applied, but for a typical application does it add 1/16", 1/8" or 1/4" to the over all thickness of the 2 sheets of drywall? I'm trying to zero in on how far out I need to leave my electrical boxes so that they are reasonably flush with the drywall once it's up. I know the distance is not critical, but I'd like to be fairly close so would like to hear from someone that's actually done it to know for sure. Thx,

-redjr

Big Red Machine · « **Reply #1 on:** 16 Feb 2014, 03:39 am »

It is very little. Probably a 1/16 max. But, when I did my walls I coiled up the wire behind the box locations and then used rework boxes. I cut the holes after the second layer, reached in and fed it into the back of the box and then attached the box to the drywall with the rework box tabs. Since the hat channel was holding up the wall, there were no studs to attach boxes to. You must be putting dd dw onto a std stud wall?

MaxCast · « **Reply #2 on:** 16 Feb 2014, 04:04 am »

I remember using a box that had an adjusting screw that once mounted you could move the box in or out with a screw.
Check Lowes or HD.

redjr · « **Reply #3 on:** 16 Feb 2014, 04:19 am »

Quote from: Big Red Machine on 16 Feb 2014, 03:39 am

It is very little. Probably a 1/16 max. But, when I did my walls I coiled up the wire behind the box locations and then used rework boxes. I cut the holes after the second layer, reached in and fed it into the back of the box and then attached the box to the drywall with the rework box tabs. Since the hat channel was holding up the wall, there were no studs to attach boxes to. You must be putting dd dw onto a std stud wall?

Yes I am. I'm not going all out with total isolation and only on full walls. I've got a couple of short walls where there will be cabinets and very little facing wallboard so I'm not doubling up there. Since the boxes do have to stick out at least 1.25" I had to go with a bigger box and one that is designed to be depth adjusted by a screw on the front. I answered my own question! Dah. I see now after examining the box a little closer that it is adjustable after the dw is up.