thermal barrier installation

[Yankee]

so, I was sent here istead of there. question is the same

If 1/2" gyp board is being used as the thermal barrier protecting foam plastic insulation, are the seams required to be mudded/taped or otherwise protected? Under 2603.4 IBC 2009, there are several tests for the thermal barrier to remain in place, is the treatment of the seams spoken to under any of these? If the gyp is cut around electrical boxes etc, is the foam sealant to be fire rated?

 

[KZQuixote]

so, I was sent here istead of there. question is the same

If 1/2" gyp board is being used as the thermal barrier protecting foam plastic insulation, are the seams required to be mudded/taped or otherwise protected? Under 2603.4 IBC 2009, there are several tests for the thermal barrier to remain in place, is the treatment of the seams spoken to under any of these? If the gyp is cut around electrical boxes etc, is the foam sealant to be fire rated?

Hi Yankee,

I couldn't see anything that addressed joint treatment and considering that there is no fire rating required I can't see how 2508.4 could be triggered.

Regarding the electrical boxes, I would think that "...or equivalent thermal barrier material that will limit the average temperature rise of the unexposed surface to no more that 250F after fifteen minutes" would preclude their penetration through the drywall. Unless of course if the contractor can convince you that the boxes are equivalent to 1/2" drywall.

Regards

Bill

 

[cda]

If you look at special approval 2603.8 it includes seams, joints

But if you also look at 2508.4 if the joints are at a wood stud they do not need to be mudded

 

[KZQuixote]

If you look at special approval 2603.8 it includes seams, jointsBut if you also look at 2508.4 if the joints are at a wood stud they do not need to be mudded

2603.4 Speaks to the joints and seams in the foam plastic not the thermal barrier.

2508.4 Speaks only to fire resistance rated assemblies.

I still think no joint treatment required.

Regards

Bill

 

[Yankee]

This is essentially what I am asking. If under any of these FM 4880, UL 1040 or UL 1715 the joints are to be treated in some way. I have started trying to look at those but some aren't available on line, I think

 

[Francis Vineyard]

The application of joint treatment may be found in the National Gypsum Fire Resistance Manual.

Yankee unless it is a rated wall that requires fire-resistant penetrations then yes, but if it is a separation wall or thermal barrier then there is no requirement for a fire stop penetration.

Another area that is of concern is the manufacturer may stipulate that the air not be circulated to other areas but says nothing about air leakage. I know it may be semantics but I believe each word is carefully chosen or intentionally left out.

At home don’t any of those books here today.

 

[Yankee]

Thank you , , , very interesting

 

[cda]

The items you reference is just the method to test the material

 

[cda]

The items you reference are just the method to test the material and criteria for passing

Not sure if you are the ahj but if you are you could ask for proof that the material passed without tape and with an outlet in place

 

[Francis Vineyard]

cda not sure if your reference is to me or Yankee but would the joint treatment be in the Handbook if not the manual?

 

[Yankee]

The items you reference is just the method to test the material

Yes, but somewhere is written what the material (or assembly) tested is, as in, does it have joint treatment or not, right?

 

[cda]

I threw these in to look to for guidnace, not as to site for enforcement

"""If you look at special approval 2603.8 it includes seams, joints

But if you also look at 2508.4 if the joints are at a wood stud they do not need to be mudded """""""""