# Securing romex to rigid foam board



## Baker2605 (Jul 18, 2013)

Need a little help. I don't do residential often but I am roughing-in a block house with foam board then furring strips on top of it. I have heard they make a staple for the foam but don't know what they are called. Maybe just use stand-off straps? Hopefully an easy code-compliant method.


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## HARRY305E (Jun 14, 2013)

Baker2605 said:


> Need a little help. I don't do residential often but I am roughing-in a block house with foam board then furring strips on top of it. I have heard they make a staple for the foam but don't know what they are called. Maybe just use stand-off straps? Hopefully an easy code-compliant method.



Can you get longer staples that will catch the beams?


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## Baker2605 (Jul 18, 2013)

What beams? The furring strips?


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## Baker2605 (Jul 18, 2013)

Sorry mods I meant to post in the residential forum


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## Deep Cover (Dec 8, 2012)

300.4 



> (d) cables and raceways parallel to framing members
> and furring strips. In both exposed and concealed
> locations, where a cable- or raceway-type wiring method is
> installed parallel to framing members, such as joists,
> ...


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## HARRY305E (Jun 14, 2013)

Baker2605 said:


> What beams? The furring strips?


What is supporting the furring strips,and what is supporting the foam?


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## nrp3 (Jan 24, 2009)

Concrete block house. Picture Florida. Foam over block. Strapping on foam. Drywall over that.


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## HARRY305E (Jun 14, 2013)

nrp3 said:


> Concrete block house. Picture Florida. Foam over block. Strapping on foam. Drywall over that.


Got it, Time to break out the Ram set and 1/2" strap's.


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## nrp3 (Jan 24, 2009)

I'd like to see how its done too.


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## HARRY305E (Jun 14, 2013)

nrp3 said:


> I'd like to see how its done too.


Same here, some pictures would be good..:thumbsup:


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## MHElectric (Oct 14, 2011)

What about cutting a chase in the foam board and securing it to the block with zip ties and masonry anchors? And then fill your chase back in with foam-in-a-can? Only problem I see is the inspector might want to look at it all before you foam it up.

I was on a commercial job where the exterior walls were getting sprayed foamed and we had to cut channels like this for some MC that got put in after they sprayed the walls.


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## 480sparky (Sep 20, 2007)

I'd cut a chase in the foam, lay the NM in, and use canned spray foam to hold it in place.

My foam method uses an electric chain saw to cut a slot. Lay the NM in and hit every 2' with a shot of canned foam.


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## Rollie73 (Sep 19, 2010)

http://www.blueridgecompany.com/image/child/3565











Available in all sizes. I use the 1/2" to 1" ones for securing pipe into the foam on ICF walls.

We cut the trench and then secure the AC-90 or the conduit or whatever method we are using with those staples.


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## MHElectric (Oct 14, 2011)

480sparky said:


> I'd cut a chase in the foam, lay the NM in, and use canned spray foam to hold it in place.
> 
> My foam method uses an electric chain saw to cut a slot. Lay the NM in and hit every 2' with a shot of canned foam.


I didn't even think about using the spray foam to secure it. Some of the sunrooms I do, have a pre-fab Styrofoam roof and Ive had to cut channels in it with little pockets left untouched to fish a wire to a flood light. Forgot about that.


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## macmikeman (Jan 23, 2007)




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## HARRY305E (Jun 14, 2013)

macmikeman said:


>


Are those 20 footers?


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## RIVETER (Sep 26, 2009)

Baker2605 said:


> Need a little help. I don't do residential often but I am roughing-in a block house with foam board then furring strips on top of it. I have heard they make a staple for the foam but don't know what they are called. Maybe just use stand-off straps? Hopefully an easy code-compliant method.


I would think that the GC would give you the method because of the possible compromise of the insulation. Surely, this is not a side job...right?


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## MHElectric (Oct 14, 2011)

RIVETER said:


> I would think that the GC would give you the method because of the possible compromise of the insulation. Surely, this is not a side job...right?


I learned something new not to long ago - seems you can get away without insulating the attic or crawlspace or exteriors walls in my area.  Yeah, no kidding. I finished a remodel on a 100 year old house last month, and that cheap Land lord managed to pass all his inspections without putting the first bit of insulation in ANYWHERE in that house. My inspector even asked about it and shot me a real funny look. I thought insulation was required, this really was something new.

This also isn't the first job he's done this on. He owns properties all over the place and his tenants are always complaining that they cant keep the place cool or warm. :laughing:


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## Baker2605 (Jul 18, 2013)

I would rather not cut a channel in the foam. The GC answer to everything is that's why I hired you. I am thinking about using 1-hole straps and tap-cons. I heard they make a "viper" strap for this application that you just nail into the foam. 

No this is not a side job it's a custom home a block away from my door. I haven't wired a home since I was a teenager. I didn't even really want this job. A residential expert I am not.


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## Baker2605 (Jul 18, 2013)

This is what I wanted. Nothing like answering your own question.
http://www.viperstrap.com/productinfo/


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## Deep Cover (Dec 8, 2012)

Baker2605 said:


> This is what I wanted. Nothing like answering your own question.
> http://www.viperstrap.com/productinfo/


The furring strips would have to be more than 1 1/4" deep to legally secure the NM to the foam.


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## nrp3 (Jan 24, 2009)

Ok, now that we solved that, what do you use for boxes and how do you secure them.


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## Deep Cover (Dec 8, 2012)

nrp3 said:


> Ok, now that we solved that, what do you use for boxes and how do you secure them.



Bracket 4 squares or a plastic equivalent secured to the furring strips (if possible). If not, then long tapcons thru the foam into the block/concrete. If the furring is too thin, there won't be any avoiding altering the foam.


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## Southeast Power (Jan 18, 2009)

MHElectric said:


> I learned something new not to long ago - seems you can get away without insulating the attic or crawlspace or exteriors walls in my area.  Yeah, no kidding. I finished a remodel on a 100 year old house last month, and that cheap Land lord managed to pass all his inspections without putting the first bit of insulation in ANYWHERE in that house. My inspector even asked about it and shot me a real funny look. I thought insulation was required, this really was something new.
> 
> This also isn't the first job he's done this on. He owns properties all over the place and his tenants are always complaining that they cant keep the place cool or warm. :laughing:


We have energy codes here so, insulation is a must.


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## Southeast Power (Jan 18, 2009)

Baker2605 said:


> Need a little help. I don't do residential often but I am roughing-in a block house with foam board then furring strips on top of it. I have heard they make a staple for the foam but don't know what they are called. Maybe just use stand-off straps? Hopefully an easy code-compliant method.


They screwed you! You have to get in ahead of the insulation.
You have a real problem.
I would scrape it off the wall with a shovel unless they were willing to remove it where you needed to work.


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## nrp3 (Jan 24, 2009)

Kitchen will be fun.


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## 480sparky (Sep 20, 2007)

Deep Cover said:


> The furring strips would have to be more than 1 1/4" deep to legally secure the NM to the foam.


Only if you install the NM right next to the strips. If you run it down between the center of the strips, you're golden.

If you run the NM horizontally _through_ the strips and they're less than 1¼", just pop on a nail plate.


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## Deep Cover (Dec 8, 2012)

480sparky said:


> Only if you install the NM right next to the strips. If you run it down between the center of the strips, you're golden.
> 
> If you run the NM horizontally _through_ the strips and they're less than 1¼", just pop on a nail plate.


I don't see what you are stating in 300.4. It does not state that when securing to furring strips this applies, it states when running parallel to.


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## Deep Cover (Dec 8, 2012)

480sparky said:


> Only if you install the NM right next to the strips. If you run it down between the center of the strips, you're golden.
> 
> If you run the NM horizontally _through_ the strips and they're less than 1¼", just pop on a nail plate.


Let's say you use your method, you fail, the inspector cites 300.4 (D), what do you cite to contradict him?


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## 480sparky (Sep 20, 2007)

Deep Cover said:


> I don't see what you are stating in 300.4. It does not state that when securing to furring strips this applies, it states when running parallel to.


300.4 covers both parallel to the strips and through them. So which part of 300.4 are you reading?


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## 480sparky (Sep 20, 2007)

Deep Cover said:


> Let's say you use your method, you fail, the inspector cites 300.4 (D), what do you cite to contradict him?


All too easy.



> nearest outside surface of the cable or raceway is not less than 32 mm (1 1 ⁄4in.) from the nearest edge of the framing member or furring


Running the cable more than 1¼ from the strips is stupendously easy to do. Just go right down the center between each one, which will most likely be 16" OC.


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## Deep Cover (Dec 8, 2012)

480sparky said:


> All too easy.
> 
> Running the cable more than 1¼ from the strips is stupendously easy to do. Just go right down the center between each one, which will most likely be 16" OC.


Nice, so as long as you are 1 1/4" away from the stud/furring, there is no need for further protection. I never caught that little nuance. :thumbsup:


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## macmikeman (Jan 23, 2007)

Baker2605 said:


> This is what I wanted. Nothing like answering your own question.
> http://www.viperstrap.com/productinfo/


Are you mad at us cause none of us had to work with that crap construction method? Well then I'm pissed at you , cause you never had to wire a single wall house.


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## MHElectric (Oct 14, 2011)

jrannis said:


> We have energy codes here so, insulation is a must.


We have energy codes too, I spray foamed around all my exterior boxes & penetrations. I have no idea how he got away with this, but from the sound of it, he's been doing it for years on all his remodels. It his calling card I guess.


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## pete87 (Oct 22, 2012)

Deep Cover said:


> Let's say you use your method, you fail, the inspector cites 300.4 (D), what do you cite to contradict him?




I think they f*ed him and he should have been in the Block with boxes / mud rings coming flush with the sheet rock . Those furring strips are what ... 1/4 or 1/2 .




Pete


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## Southeast Power (Jan 18, 2009)

480sparky said:


> Only if you install the NM right next to the strips. If you run it down between the center of the strips, you're golden.
> 
> If you run the NM horizontally _through_ the strips and they're less than 1¼", just pop on a nail plate.


What we do here on concrete block construction is zigzag it down the wall between two fur ring strips, stapling it to the strips and install a kick plate where it is stapled to the strips.


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## 480sparky (Sep 20, 2007)

pete87 said:


> I think they f*ed him and he should have been in the Block with boxes / mud rings coming flush with the sheet rock . Those furring strips are what ... 1/4 or 1/2 .
> 
> 
> 
> ...


Those aren't furring strips in the photo. They're 2x4s.


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## pete87 (Oct 22, 2012)

480sparky said:


> Those aren't furring strips in the photo. They're 2x4s.


My bad , i thought the OP said furring strips .







Pete


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## 480sparky (Sep 20, 2007)

pete87 said:


> My bad , i thought the OP said furring strips .
> 
> 
> 
> ...


I thought you were referring to my photos. If not, then it's MY bad.

We now return you to your regularly scheduled program....


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## Baker2605 (Jul 18, 2013)

macmikeman said:


> Are you mad at us cause none of us had to work with that crap construction method? Well then I'm pissed at you , cause you never had to wire a single wall house.


 I am not mad well maybe at myself for not buying the stupid things before. What makes it a crap construction method? Its a block wall with 3/4 rigid foam board held in place by 3/4 furring strips. So I just brought the romex down between the furring strips to a 1 1/2 4sq and use those clips tho secure the romex.


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