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Combustible spaces

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gtfire

Mechanical
Feb 17, 2010
10
NFPA 13 - 2007, Sec 11.2.3.1.4 (3) that unless sec 11.2.3.1.4.4 is met tnen the design area is to be increased to 3000 ft2 for the systme or portion of system that is ADJACENT to the qualifying combustible concealed space. If this is a ceiling space then is the ADJACENT space the rooms below it or an area next to it even if it is fully sprinklered non-combustible.
 
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Unless the requirements of 11.2.3.1.4(4) are met for buildings having unsprinklered combustible concealed spaces, as described in 8.15.1.2 and 8.15.6, the minimum area of sprinkler operation for that portion of the building shall be 3000 ft2 (279 m2). The design area of 3000 ft2 (279 m2) shall be applied only to the sprinkler system or portions of the sprinkler system that are adjacent to the qualifying combustible concealed space.


ad·ja·cent (? j??s?nt)

adjective

near or close (to something); adjoining



sounds like the answer to yuor question would be YES

but seems like it would be case by case


and also why is a combustilble space not sprinkled or meet one of the exceptions not to?????
 
In this case the combustible concealed spaces meet 8.15.1.2.6 but as such, are not filled completely with insulation, therefore, as per section 11.2.3.1.4(3) are met then the design area in the adjacent space requires the increase in design area to 3000 ft2.
 
We have always taken this to mean the ceiling sprinklers in the area as well as the floor above. I believe I got this from AFSA many years ago.

Travis Mack
MFP Design, LLC
 

gtfire ::::



so you say this area is NOT sprinkled and does not meet one of these???:::


(4) The following unsprinklered concealed spaces shall not require a minimum area of sprinkler operation of 3000 ft2 (279 m2):
(a) Noncombustible and limited-combustible concealed spaces with minimal combustible loading having no access. The space shall be considered a concealed space even with small openings such as those used as return air for a plenum.
(b) Noncombustible and limited-combustible concealed spaces with limited access and not permitting occupancy or storage of combustibles. The space shall be considered a concealed space even with small openings such as those used as return air for a plenum.
(c) Combustible concealed spaces filled entirely with noncombustible insulation.
(d)* Light or ordinary hazard occupancies where noncombustible or limited combustible ceilings are directly attached to the bottom of solid wood joists so as to create enclosed joist spaces 160 ft3 (4.5 m3) or less in volume, including space below insulation that is laid directly on top or within the ceiling joists in an otherwise sprinklered attic.
(e)* Concealed spaces where rigid materials are used and the exposed surfaces have a flame spread index of 25 or less and the materials have been demonstrated to not propagate fire when tested in accordance with NFPA 255, Standard Method of Test of Surface Burning Characteristics of Building Materials, extended for an additional 20 minutes in the form in which they are installed in the space.
(f) Concealed spaces in which the exposed materials are constructed entirely of fire-retardant treated wood as defined by NFPA 703, Standard for Fire Retardant–Treated Wood and Fire-Retardant Coatings for Building Materials.
(g) Concealed spaces over isolated small rooms not exceeding 55 ft2 (5.1 m2) in area.
(h) Vertical pipe chases under 10 ft2 (0.93 m2), provided that in multifloor buildings the chases are firestopped at each floor using materials equivalent to the floor construction and where such pipe chases shall contain no sources of ignition, piping shall be noncombustible, and pipe penetrations at each floor shall be properly sealed.
(i) Exterior columns under 10 ft2 (0.93 m2) in area formed by studs or wood joist, supporting exterior canopies that are fully protected with a sprinkler system.




MY QUESTION is if it does not meet one of the above, then why aren't there sprinklers in the space??????????????

Am I missing some other exception to sprinklers????
 
Because Sec 11.2.3.1.4(3) essentially states that if 11.2.3.1.4(4) are not met but the construction requirements of Sec 8.15.1.2 and 8.15.6 are THEN the design area is increased to 3000 ft2 in the adjacent areas.
 
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