Securing Romex to block wall with 1" Rigid Foam board and 1/2" fur strips on top of foam board

J

Jstumpp

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Location
Florida
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Contractor
Currently setting up to rough out a 10k Sq ft custom home. I have not done a high end custom residential buildout in a couple years and am wondering what new materials are commonly used to secure Romex to the foam boards now.

At one point duct tape was allowed in our area, then just staples. I like to keep up on new products and common installation practices. Any recommendations would be great.
 
When I see things like "1" Rigid Foam board and 1/2" fur strips on top of foam board" I just scratch my head and ask why?
 
infinity said:
When I see things like "1" Rigid Foam board and 1/2" fur strips on top of foam board" I just scratch my head and ask why?
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I have to tell myself, "Who am I to tell people how to spend their money" in this situation. Shout out to the builder for selling it, though. Makes the job easier for us, no chipping for boxes on exterior walls. Which, with the layout of the home, is about 75% of the boxes.
 
infinity said:
You frame a stud wall. You can use metal studs that are only 1 5/8" deep so you don't lose much real estate. Furring strips are for hacks. :oops:
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I'm assuming the furring strips are actually battens that secure the foamboard to the block wall and provide a screwbase for the wall finish. Seems reasonable and provides for continuous insulation while avoiding the thermal bridging of metal studs. Even better would be insulation board with wood or plastic studs precast into them, if such a product exists.

Anyway, there's multiple ways to deal with insulating a block wall, they each have their pros and cons.

Cheers, Wayne
 
It's been years since I've done residential, but when I did a home that used foam board insulation, the inspector allowed me to use a scrap piece of the NM jacket and loop it around the cable, then drive a cut nail (case hard) through the piece of sheath and into the cinder block. It was quick and easy and secured the cable really nice.
 
infinity said:
Not only that a standard 1.5"-1900 box with a raised cover is more than 1.5" thick.
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The raised cover matches the depth of the drywall installed. 1.5" box depth meets the 1" foam board and 1/2" fur. 1/2" mud ring for 1/2" drywall.

Cutting the foam board would be no different than having to recesse the box in the block. Standard insulation would still go around the box.
 
wwhitney said:
I'm assuming the furring strips are actually battens that secure the foamboard to the block wall and provide a screwbase for the wall finish. Seems reasonable and provides for continuous insulation while avoiding the thermal bridging of metal studs. Even better would be insulation board with wood or plastic studs precast into them, if such a product exists.

Anyway, there's multiple ways to deal with insulating a block wall, they each have their pros and cons.

Cheers, Wayne
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This would likely be the correct way to phrase what im dealing with, thank you for the clarification
 
Jstumpp said:
The raised cover matches the depth of the drywall installed. 1.5" box depth meets the 1" foam board and 1/2" fur. 1/2" mud ring for 1/2" drywall.

Cutting the foam board would be no different than having to recesse the box in the block. Standard insulation would still go around the box.
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A 1900 box with an attached raised cover is actually more than 1.5" deep when the two are assembled together.
 
infinity said:
A 1900 box with an attached raised cover is actually more than 1.5" deep when the two are assembled together.
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Well of course. Box is 1.5" deep which will be flush to the face of the fur once foam is cut and box is mounted to the block. Im unaware if you are talking about the 1/32" raise from the face of the mud ring, but that would be negligible and I may be missing your intended point by this comment.
 
Jstumpp said:
Well of course. Box is 1.5" deep which will be flush to the face of the fur once foam is cut and box is mounted to the block. Im unaware if you are talking about the 1/32" raise from the face of the mud ring, but that would be negligible and I may be missing your intended point by this comment.
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The combination of the cover and the heads 8/32 screws will bulge out the Sheetrock unless you use a 1.25" deep box.
 
infinity said:
The combination of the cover and the heads 8/32 screws will bulge out the Sheetrock unless you use a 1.25" deep box.
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I've never had that become an issue or seen any bulging of sheet rock when installing a 1900 box flush with any framing member and installing the cover on top ever. Are you implying you recess your 1900 boxes on framed walls to account for the flange of the mud ring?
 
Jstumpp said:
I've never had that become an issue or seen any bulging of sheet rock when installing a 1900 box flush with any framing member and installing the cover on top ever.
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Bracket boxes are set back to compensate for the thickness of the cover plate and screws which should be flush with the face of the stud. There are times when a box is proud of the stud face and it is noticeable unless the taper levels the area with mud. Good way to PO a fussy GC.

-Hal
 
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