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Fire Rated Construction

K

Kanzas

Registered User
Joined
Jul 13, 2011
Messages
11
Where in the IBC 2009 does it state that fire rated assemblies in the Gypsum Association Fire Resistance Design Manual meet the requirements for IBC fire rated assemblies? Thanks.
 
703.2 Fire-resistance ratings.

The fire-resistance rating of building elements, components or assemblies shall be determined in accordance with the test procedures set forth in ASTM E 119 or UL 263 or in accordance with Section 703.3.

They have been tested to the applicable standards
 

From the GA Manual

FIRE RESISTANCE TESTS

​
All fire-resistance classifications described in thisManual are derived from full-scale fire tests conductedin accordance with the requirements of ASTM E 119 orCAN/ULC-S101 (as amended and in effect on the dateof the test) by recognized independent laboratories.Fire-resistance classifications are the results of testsconducted on systems made up of specific materials put

​
together in a specified manner.

 
IBC 2009

TABLE 721.1(1)

Footnote

m. Generic fire-resistance ratings (those not designated as PROPRIETARY* in the listing) in GA 600 shall be accepted as if herein listed.

TABLE 721.1(2)

Footnote

q. Generic fire-resistance ratings (those not designated as PROPRIETARY* in the listing) in the GA 600 shall be accepted as if herein listed.
 
It is unfortunate that the GA manual lacks assembly details for intersections.

For example, where a rated wall is intersected by a non-rated wall or by a non-rated floor assembly.

It seems a lot of designers just invent details that might seem plausible,

But have not actually been tested and listed.

Or am I missing something?
 
garrett said:
It is unfortunate that the GA manual lacks assembly details for intersections.For example, where a rated wall is intersected by a non-rated wall or by a non-rated floor assembly.

It seems a lot of designers just invent details that might seem plausible,

But have not actually been tested and listed.

Or am I missing something?
Click to expand...
Many of the manufactures have rated to nonrated assemblies.

The GA600 is Gypsum Association Fire Resistance Design Manual not a Gypsum detail manual.
 
garrett said:
It is unfortunate that the GA manual lacks assembly details for intersections. For example, where a rated wall is intersected by a non-rated wall or by a non-rated floor assembly. It seems a lot of designers just invent details that might seem plausible, But have not actually been tested and listed. Or am I missing something?
Click to expand...
UL lacks details for intersections as well...what's your point?
 
Well, for example,

how does one maintain the fire-resistive rating of a multi-story rated wall when there is a non-rated floor/ceiling assembly that intersects it and bears on it at intermediate levels. This occurs at townhouses sharing a common wall.

Seems simple enough, but researching precedents I find that the majority of the time architects details are not based on an actual tested assembly, but something that is invented to look reasonable enough.

It would be nice if UL had some drawings of conditions like these that are tested.
 
how does one maintain the fire-resistive rating of a multi-story rated wall when there is a non-rated floor/ceiling assembly that intersects it and bears on it at intermediate levels. This occurs at townhouses sharing a common wall.
Click to expand...
You can't and therfore that dseign would not be permitted
 
garrett said:
Well, for example, how does one maintain the fire-resistive rating of a multi-story rated wall when there is a non-rated floor/ceiling assembly that intersects it and bears on it at intermediate levels. This occurs at townhouses sharing a common wall.

Seems simple enough, but researching precedents I find that the majority of the time architects details are not based on an actual tested assembly, but something that is invented to look reasonable enough.

It would be nice if UL had some drawings of conditions like these that are tested.
Click to expand...
Once again, refer to manufactures Area Separation Fire Wall Details. If you test an assembly as you describe, it will fail.
 
mtlogcabin said:
You can't and therfore that dseign would not be permitted.
Click to expand...
What do you mean, "you can't?"

Are you saying that if the wall is fire-rated, then the floor/ceiling assembly must be rated too?

What is your suggested alternative?

mark handler said:
Once again, refer to manufactures Area Separation Fire Wall Details. If you test an assembly as you describe, it will fail.
Click to expand...
The situation I describe is NOT an Area Separation Fire Wall, it is a 1-hour fire-resistive common wall, per R302.2, Excpetion.

An Area Separation Fire Wall is a completely different thing.

There are some published details out there for what I describe, but not too many, and mostly by manufacturers of engineered lumber products.
 
How in the world do you think you can end a 1-hour fire-resistive common wall in an unrated floor system

It doesnt work, the fire wall must extend to the foundation, without "holes" in it.
 
2009 IRC

R302.2.1 Continuity.

The fire-resistance-rated wall or assembly separating townhouses shall be continuous from the foundation to the underside of the roof sheathing, deck or slab.......

What you describe is a membrane penetration and will not meet the requirements of R302.4.1.

R302.4.2 Membrane penetrations.

Membrane penetrations shall comply with Section R302.4.1.
 
R302.2.1 Continuity says rated "wall or assembly" shall be continuous,

it does not say that you can't change from one type of assembly to another as you go up.

The critical element is that the fire-resistance is continuous, but the assembly may change.

Are you saying they need to be balloon-framed? No bearing on the common-wall? No beam-pockets allowed either? I disagree with that interpretation.

R302.4.2 Membrane penetrations is written for recessed fixtures, not for changes in assembly from one type to another.

I interpret that one may use a continuous rim-board assembly, with continuous 5/8" Type X Gyp. on each side that provides continuous fire-resistive rating. No "holes" in it.

Structural independence is not required.
 
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GARRRTT

Your "wall or assembly" as shown is not continuous. The wall ends at the floor, then starts again.

One option is to Provide solid blocking, full width of the plate

Another option is to go to the trus joit website and use an approved detail

It is a good thing the planchecker redflagged this detail
 
I have seen this design approach before and it could work if it provides a one-hour protection from unit to unit.

1 The fire side is from the ceiling assembly. One layer of Type X has 40 minutes of assigned protection. How much time do you get for the LVL rim board?

2 What time frame is given to the second floor 2X sill plate?

Nobody around here answered those questions?

They wanted to install 2 layers of Type X which would work, but in the field came up short on the minimum bearing requirements for the I-Joist

May look good on paper but difficult to construct.
 
garrett said:
Well, for example, how does one maintain the fire-resistive rating of a multi-story rated wall when there is a non-rated floor/ceiling assembly that intersects it and bears on it at intermediate levels. This occurs at townhouses sharing a common wall.
Click to expand...
My recommendation would be to hire an architect familiar with the typology.
 
Most architects, including those "familiar with the typology" do not get it right, they make it up.

Your response is basically saying you don't know the answer.

So if you rely on an architect with some sort of secret insight into the issue, how are building officials supposed to evaluate the proposed design?

I appreciate more constructive advice.
 
garrett said:
I appreciate more constructive advice.
Click to expand...
You were given constructive advice which you chose to ignor.

It did not fit your idea.

Side note your assembly probably will not meet your SOUND TRANSMISSION requirements
 
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Okay, but the CRC (based on 2009 IRC) does not have mandatory sound transmission requirements. But of course we want to provide a decent level of separation. It is a staggered stud wall assembly.

"APPENDIX K

SOUND TRANSMISSION

The provisions contained in this appendix are not mandatory unless specifically referenced in the adopting ordinance.

(Note: See Section 1207 “Sound Transmission” of the California Building Code, Title 24, Part 2, for requirements applicable to structures in this code.)

SECTION AK 101

GENERAL

AK101.1 General. Wall and floor-ceiling assemblies separating dwelling units including those separating adjacent townhouse units shall provide air-borne sound insulation for walls, and both air-borne and impact sound insulation for floor-ceiling assemblies..."
 
mark handler said:
You were given constructive advice which you chose to ignor.
Click to expand...
I think he is practicing as or like an architect...and the advice would have been better directed to the Owner.
 
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