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Acoustical foam on wall

F

FLSTF01

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Joined
Jan 15, 2015
Messages
122
Location
Connecticut
I have a question I need some help on. There is a church (A-3) in my jurisdiction that has a small 7 x 7 x 7 foot high booth on the stage for the drummer to play in. They say they need the booth so they can control the sound by using a microphone setup inside the booth. The booth is made of a simple 2x4 frame with 1/2 inch plywood walls, there is no door. The walls have 2 inch thick wedge-type foam rubber to absorb sound. The foam is made by Auralex Acoustics and the model is Studiofoam Wedge. I have documentation that it is a class A product with flame spread of 20 and smoke developed index of 300. On the ceiling, there are panels that are made by Sorber and they are called STC baffles. The ceiling panels are also class A with a flame spread of 0 and a smoke index of 65.

This is a non-sprinklered one floor building with a walkout basement below, also part of the church. There is sufficient egress and the sanctuary area where the stage is has a cathedral ceiling about 22 feet high and the floor area is about 3500 sf.

My question: Under the 2003 IBC section 2603.4, a thermal barrier is required. Am I interpreting the code wrong, or is there an exception or a different code I should be referencing for sound booths? A follow-up question is that they want to put a door on this booth. Your assistance is appreciated!
 
The cage is not movable, at least it's not really meant to be movable. They had a jury-rigged duct fan inside but I made them remove it. There is only a microphone and the XLR cable for it inside of the cage.
 
You need more info/documentation. I did not find anything on their website that indicated compliance with 2603.10

2604.1 General.

Plastic materials installed as interior finish or trim shall comply with Chapter 8. Foam plastics shall only be installed as interior finish where approved in accordance with the special provisions of Section 2603.10. Foam plastics that are used as interior finish shall also meet the flame-spread index requirements for interior finish in accordance with Chapter 8. Foam plastics installed as interior trim shall comply with Section 2604.2.

2603.10 Special approval.

Foam plastic shall not be required to comply with the requirements of Sections 2603.4 through 2603.8 where specifically approved based on large-scale tests such as, but not limited to, NFPA 286 (with the acceptance criteria of Section 803.2), FM 4880, UL 1040 or UL 1715. Such testing shall be related to the actual end-use configuration and be performed on the finished manufactured foam plastic assembly in the maximum thickness intended for use. Foam plastics that are used as interior finish on the basis of special tests shall also conform to the flame spread and smoke-developed requirements of Chapter 8. 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.
 
I like your train of thought, CDA. I would like to try to find a way to rationally allow it, I just need to ensure I can back up my decision with Code.

But please realize, I am in CT, next to RI. We remember the Station Nightclub fire like it was yesterday.
 
I think the "special test" is like a VIF....if it has all of the flame spread ratings and such, I would check what your FM might entertain, but stick a plumbing torch up to it for a bit and see what happens when you take it away....self extinguish, shouldn't be an issue...Or the spray to go over it now should be acceptable...

2603.4 Thermal barrier.

Except as provided for in Sections 2603.4.1 and 2603.10, foam plastic shall be separated from the interior of a building by an approved thermal barrier of 1/2-inch (12.7 mm) gypsum wallboard or a material that is tested in accordance with and meets the acceptance criteria of both the Temperature Transmission Fire Test and the Integrity Fire Test of NFPA 275. Combustible concealed spaces shall comply with Section 718.
 
Last edited by a moderator:
I like your train of thought, CDA. I would like to try to find a way to rationally allow it, I just need to ensure I can back up my decision with Code.But please realize, I am in CT, next to RI. We remember the Station Nightclub fire like it was yesterday.
Click to expand...
So what section of the code are you going to use to make the requirement
 
Fixed or movable walls and partitions, paneling, wall pads and crash pads applied structurally or for decoration, acoustical correction, surface insulation or other purposes shall be considered interior finish if they cover 10 percent or more of the wall or of the ceiling area, and shall not be considered decorative materials or furnishings.

If the building had a fire sprinkler system would you also require a fire sprinkler head in the drum cage?
 
I wrote the abatement order to remove the wedge foam. Even though it has a class A rating, when plastic foam is used as a wall covering, it must be tested as an assembly. 2003 IBC sections 801.2.2; 2603.8 and 2604 apply. The Sorber panels are permissible because they are an assembly already, meant to be just tacked to whatever wall surface there is.

Thank you all for your assistance!
 
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