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Posted By: KBSHORTS Wiring in SIPs - 05/02/06 12:40 PM
We are currently working on a building with exterior walls constructed of prefabricated SIPs. Any nessecary wiring is run in a chase cut out with a hot knife and MC cable laid in the cutout, after the cable is installed the insulation is trimmed and reinstalled with metallic tape used to seal the over it. We were instructed by the manufacturers rep. on-site that this was acceptable. Our local AHJ has asked raised a concern about heat buildup in the cable as installed and wants documentation that this installation is acceptable. The only response I can get fron the manufacturer is " that is how we always do it". Has anyone else run into this? If so, how was it finally resolved?
KB
Posted By: Scott35 Re: Wiring in SIPs - 05/03/06 02:33 AM
This situation may be one where you need to
"let the Manufacturer and the Building Department Fight It Out"

Try looking through the Company's website for documents which support the claim(s), then present these items to the Inspector or Building Department to see if they accept it or not.

If no documents are available to support the claim(s), or the AHJ (Building Department) does not accept the documents, let the Manufacturer take over, and come up with a method which will conform to your DBS's minimums plus not be a complete loss for you and the Mfr.

Good luck, and let us know what the outcome is.

Scott35
Posted By: George Little Re: Wiring in SIPs - 05/03/06 02:46 AM
Am I the only one that does not know what a "SIP" or a "DBS" is? It would be nice if you guys would spell thing out for us dummies.
Posted By: BigB Re: Wiring in SIPs - 05/03/06 03:06 AM
"Am I the only one that does not know what a "SIP" or a "DBS" is? It would be nice if you guys would spell thing out for us dummies."

No George, you're not the only one. But myself, I have always subscribed to the idea that it's better to remain silent and let everyone think you don't know anything than to open your mouth and prove it. [Linked Image]
Posted By: skingusmc Re: Wiring in SIPs - 05/03/06 03:15 AM
George Little -

"Am I the only one that does not know what a "SIP" or a "DBS" is? It would be nice if you guys would spell thing out for us dummies."

Nope, I would be one of the other dummies that doesn't know what "SIP" and DBS" means.

BigB -

"No George, you're not the only one. But myself, I have always subscribed to the idea that it's better to remain silent and let everyone think you don't know anything than to open your mouth and prove it. "

But if I stay quiet, then how will I "know" what "I don't know"?

Besides, how will all the other dummies that don't speak up find out (g).
Posted By: Larry Fine Re: Wiring in SIPs - 05/03/06 04:11 AM
I believe SIP means "Structural Insulated Panel", and is a pre-sheathed bunk of insulation. Not sure about DBS beyond satellite TV.
Posted By: Tesla Re: Wiring in SIPs - 05/03/06 06:37 AM
Department of Building Standards ?
Posted By: e57 Re: Wiring in SIPs - 05/03/06 07:19 AM
Is a SIP simular to an API?
Posted By: KBSHORTS Re: Wiring in SIPs - 05/03/06 10:40 AM
Sorry guys! A SIP is a structural insulated panel. These are styrofoam filled metal stud wall panels. They come in prefabricated panels and are stood up on site. The building looks like a big white styrofoam cooler. Siding and sheetrock will be installed as usual. The manufacturer has no info. avalible on-line and so far has not been able to provide any.
KB
Posted By: jaschmidt Re: Wiring in SIPs - 05/03/06 12:49 PM
I believe what your AHJ is looking for is a sealed letter from the company engineer that this product is safe to use in these walls. As an inspector I required letters myself, Good Luck.
Posted By: gfretwell Re: Wiring in SIPs - 05/03/06 03:43 PM
What is the difference between MC in a SIP wall and any other cable installed in an insulated wall? Shooting foam in an exterior wall is pretty common and some kind of insulation is pretty much required by law. For that matter a buried cable is also very much thermally insulated.

I think this is just an inspector who is confused by something new. I saw a similar case with a Y-tong concrete structure. The Fire Marshall had never seen it before and refused to believe the state engineer's documents on the plan. It took about 3 months of substantiation from the NRTL, the manufacturer and the engineer to get the CO.
Posted By: dlhoule Re: Wiring in SIPs - 05/03/06 06:26 PM
Is a SIP simular to an API?

I know what a SIP is; what is an API?
Though the SIPs I am familiar with are slightly different than those described above. The SIPs that I have seen are just styrofoam type insulation sandwiched between OSB. They come with chase for wiring anyhere you want them placed. Typically 12" to 18" off floor for outlets and 48" for switches as well as specified height for countertop receptacles and out side lighting. There are also verticle chases where ever specified.

I might add that I think they are a pain in the A** to wire, but they provide excellent insulation for a home.
Posted By: e57 Re: Wiring in SIPs - 05/05/06 12:26 AM
API is a brand name of what I assume is very simular, that I have delt with before. BIG PITA!
http://www.apipanel.com/

The ones I was having a problem with were double sided aluminum ones. The arch's had not compansated for wiring in the design at all in wall thickness. As these things constituted structure of major portion of the exterior walls they cuold not be cut all but minimumaly for penetrations. Like a shear-wall.... (Which may be why your inspector is worried?) Sending all into a tizzy when they decided to use them as both the interior and exterior as the same panel. So my question was how would you like the conduit to look?! "Conduit?!" We ended up piping on one, and they sandwiched that and the boxes with 2" rings through another thin one, for the same appearance they had sold the customer on, at a heafty tune of $$$$$.

Back when I was looking into this, I think there were some that have "Pre-installed electrical Chases" in them. (Oh, how I hate to hear the word, "Chase". Makes me think of landscRapers doing thier own wiring, but that is a different story.....) Which would have been nice for the boss to realize before they poured the slab they were sitting on.... But then that would also require some sort of coordination between trades, that rarely happens, so the Chases" line up with each other. And so they go where you want them to go. Good luck! [Linked Image] Either way, I have never done it, but have little confidence of the system being productive for our trade.....
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