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"Hotwall" wall covering

ajweaver

Bronze Member
Joined
Oct 27, 2009
Messages
41
Location
Austin, TX
Entry is a 14'ceiling

Room next to it is a 10' ceiling.

Typically I see T-ply covering on what we call a "hotwall"

Today I saw blue foam board there instead.

I have never seen it used for an interior wall like this.

2006 IRC

It is not seperated from the interior by gypsum per 314 is where I think I am going-

Any input?

Aaron
 
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Don't quite understand.

Are you talking about draftstopping?
 
Its like a knee wall.

The ceiling height is 14' in one room, and the room next to it the ceiling height is 10'.

There is a 4' higher wall that usually has tply sheathing to hold the insulation in place on the upper wall.

Ill snap a pic tomorrow while I am out in the field and try and to post it late tomorrow.
 
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Not familiar with the term "hotwall" but similarly with concealed spaces along the exterior walls between the floor and ceiling there would normally be unfaced insulation.

Assuming here is a 4 ft. span between the ceiling and floor insulated with Styrofoam boards. I usually substantiate the code with the manufacturers ICC ESR report; it will probably state the same requirements; "separated from the interior with an approved 15 minute thermal barrier".

There is often confusion about the difference between separation and covered. It will be your judgment at the time of completion if this is met and whether any openings or penetrations in the ceiling and floors maintain this separation. Otherwise have them use Thermax, T-Ply or equivalent.
 
Does the attic meet this requirement

R314.5.3 Attics.

The thermal barrier specified in Section 314.4 is not required where attic access is required by Section R807.1 and where the space is entered only for service of utilities and when the foam plastic insulation is protected against ignition using one of the following ignition barrier materials:.....

If so will this apply

The above ignition barrier is not required where the foam plastic insulation has been tested in accordance with Section R314.6.

Is one of these test printed on the product?

R314.6 Specific approval.

Foam plastic not meeting the requirements of Sections R314.3 through R314.5 shall be specifically approved on the basis of one of the following approved tests: NFPA 286 with the acceptance criteria of Section R315.4, FM4880, UL 1040 or UL 1715, or fire tests related to actual end-use configurations. The specific approval shall be based on the actual end use configuration and shall be performed on the finished foam plastic assembly in the maximum thickness intended for use. Assemblies tested shall include seams, joints and other typical details used in the installation of the assembly and shall be tested in the manner intended for use.

Depending on what is in the attic

It may be okay as is

It may need just an ignition barrier

It may need a thermal barrier
 
Perfect..thanks.

Sometimes I am reading a code section I am not very familiar with, the more I read it-the more I confuse myself.

Thanks for breaking it down.

mtlogcabin said:
Does the attic meet this requirementR314.5.3 Attics.

The thermal barrier specified in Section 314.4 is not required where attic access is required by Section R807.1 and where the space is entered only for service of utilities and when the foam plastic insulation is protected against ignition using one of the following ignition barrier materials:.....

If so will this apply

The above ignition barrier is not required where the foam plastic insulation has been tested in accordance with Section R314.6.

Is one of these test printed on the product?

R314.6 Specific approval.

Foam plastic not meeting the requirements of Sections R314.3 through R314.5 shall be specifically approved on the basis of one of the following approved tests: NFPA 286 with the acceptance criteria of Section R315.4, FM4880, UL 1040 or UL 1715, or fire tests related to actual end-use configurations. The specific approval shall be based on the actual end use configuration and shall be performed on the finished foam plastic assembly in the maximum thickness intended for use. Assemblies tested shall include seams, joints and other typical details used in the installation of the assembly and shall be tested in the manner intended for use.

Depending on what is in the attic

It may be okay as is

It may need just an ignition barrier

It may need a thermal barrier
 
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