Garage Ventilation System

							SUPPLEMENTAL CORRECTION SHEET FOR GARAGE VENTILATION SYSTEM

This is intended to provide uniform application of the codes by the plan check staff and to help the public apply the codes correctly. PLAN DETAILS G G G G 1. 2. 3. 4. Provide floor plan (1/8" or larger scale) showing locations of all exhaust ducts/outlets, make-up air ducts/inlets, and proposed air flow quantities. (95.113.2.4) Provide roof plan showing a permanent roof access, distance from property lines, and locations of all roof equipment. (95.506.9.2) Provide make up air. (95.505.3). Show the termination point of the garage exhaust. Exhaust outlets shall terminate not less than 10 feet from property line, 3 feet from exterior wall or roof, 10 feet from openings into the building, 10 feet above adjoining grade. (95.506.9.2) Provide combination fire/smoke dampers where the garage exhaust ducts penetrate the fire rated shaft. (91.713.10, 91.713.11). Provide combination fire/smoke dampers where the make up air ducts penetrate a fire rated shaft. (91.713.10, 91.713.11). Show the location of the carbon monoxide sensors.

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5. 6. 7.

CALCULATIONS G G G 1. 2. 3. Provide exhaust calculations and method used. (91.1202.2.7) For open parking garages, provide calculations per Section 91.311.9 of Los Angeles Building Code. (91.311.9) Provide calculations showing that the exhaust fan is capable of uniformly exhausting 1.5 cfm per square foot of gross floor area. (91.1202.2.7).

NOTES ON PLANS

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Provide manufacturer’s literature or catalog for: a. b. Exhaust fans showing compatible material and fan performance curve or chart. (95.503.1) Make-up air fan showing fan performance curve or chart. (95.503.1)

LADBS-Corr.Lst.29 (11/2002)6/1/2005) PC/MECH/Corr.Lst.29 (Rev.

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2. 3. 4. 5.

Ducts installed in locations subject to physical damage shall be protected by suitable guards or barriers. (95.610.8) Do not connect any other ventilation system to the garage ventilation system. (95.505.1) Ducts shall be made of metal or poured in concrete (dry wall is not acceptable). (95.610.1) Approval letter and manufacturer’s recommendations for the installation of the carbon monoxide detectors. (95.111.0)

LADBS-Corr.Lst.29 (11/2002) 6/1/2005) PC/MECH/Corr.Lst.29 (Rev.

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EXAMPLES Example 1: Garage dimensions are 80' x 120' what are the requirements for exhaust and make-up air. Answer: Per Section 91.1202.2.7 of Los Angeles Building Code Q exh = 1.5 cfm x Area (ft)² (ft)² Q exh = 1.5 x (80 x 120 ) = 14,400 cfm Therefore , Q make-up = 14,400 cfm (ft³/min.)

Example 2: For the garage dimensions given in example #1 by using the alternative method or 38 cars the amount of exhaust will be as follows: Q exh = 2.5% x (14000 cfm moving vehicle ) x (# of cars)

Q exh = 0.025 x 14000 x 38 = 13,300 cfm Since the exhaust comes less than 14,000 cfm, the fan capacity shall be upgraded to 14,000 cfm, which is the minimum required under this method.

LADBS-Corr.Lst.29 (11/2002)6/1/2005) PC/MECH/Corr.Lst.29 (Rev.

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