Los Angeles Municipal Code Div. 15 Roofs and Roof Structures

(Division Amended by Ord. No. 179,324, Eff. 12/10/07, Oper. 1/1/08.)

Section

Chapter 15 of the CBC is adopted by reference with the following exceptions, modifications and additions:

Section 1505 of the CBC is adopted by reference, except Sections 1505.1, 1505.6 and 1505.7 of the CBC are not adopted and in lieu, Section 91.1505.1 is added.

91.1505.1. General. (Amended by Ord. No. 185,587, Eff. 7/16/18.) Roof assemblies shall be divided into the classes defined below. Class A, B and C roof assemblies and roof coverings required to be listed by this section shall be tested in accordance with ASTM E 108 or UL 790. The minimum roof coverings installed on buildings shall comply with CBC Table 1505.1 based on the type of construction of the building.

EXCEPTION: Skylights and sloped glazing shall comply with Division 12, Article 1, Chapter IX of the LAMC.

No wood shake or wood shingle roof covering is permitted anywhere in the City.

(Amended by Ord. No. 187,719, Eff. 1/23/23.)

Section 1507 of the CBC is adopted by reference, except Table 1507.3.7 of the CBC is not adopted and, in lieu, Los Angeles Municipal Code Table 1507.3.7 is added.

TABLE 1507.3.7

CLAY AND CONCRETE TILE ATTACHMENT a, b, c (Amended by Ord. No. 181,758, Eff. 8/8/11.)

GENERAL – CLAY OR CONCRETE ROOF TILE

Maximum basic Mean roof Roof slope up to <3:12 Roof slope 3:12 and over wind speed (mph) height (feet) 85 0-60 Two fasteners per tile. Two fasteners per tile. 100 0-40 The head of all tiles shall be nailed. The nose of all eave tiles shall be fastened with approved clips. All rake tiles shall be nailed with two 100 >40-60 nails. The nose of all ridge, hip and rake tiles shall be set in a bead of roofer’s mastic. The fastening system shall resist the wind forces in CBC Section 110 0-60 1609.5.3. The fastening system shall resist the wind forces in CBC Section 120 0-60 1609.5.3. The fastening system shall resist the wind forces in CBC Section 130 0-60 1609.5.3. The fastening system shall resist the wind forces in CBC Section All >60 1609.5.3.

INTERLOCKING CLAY OR CONCRETE ROOF TILE WITH PROJECTING ANCHOR LUGS d, e

(Installations on solid sheathing with battens) Roof slope Roof slope Roof slope Maximum basic Mean roof wind speed (mph) height (feet) up to < 5:12 5:12 < 12:12 12:12 and over 85 0-60 One fastener per One fastener required for tile. Tiles with every tile. Tiles with Minimum slope is installed weight installed weight less than 4:12. One fastener less than 9 lbs./sq. 100 0 - 40 per tile. ft. require a 9 lbs./sq. ft. require a minimum of one fastener minimum of one per tile. fastener per tile. The head of all tiles shall be nailed. The nose of all eave tiles shall be fastened with approved clips. All rake tiles shall be nailed with two 100 >40-60 nails. The nose of all ridge, hip and rake tiles shall be set in a bead of roofer’s mastic. The fastening system shall resist the wind forces in CBC Section 110 0-60 1609.5.3. The fastening system shall resist the wind forces in CBC Section 120 0-60 1609.5.3. The fastening system shall resist the wind forces in CBC Section 130 0-60 1609.5.3.

The fastening system shall resist the wind forces in CBC Section All >60 1609.5.3.

INTERLOCKING CLAY OR CONCRETE ROOF TILE WITH PROJECTING ANCHOR LUGS

(Installations on solid sheathing without battens) Maximum basic Mean roof Minimum roof slopes 4 units vertical in 12 units horizontal wind speed (mph) height (feet) Maximum slope 7 units vertical in 12 units horizontal 85 0-60 One fastener per tile. 100 0-40 One fastener per tile. The head of all tiles shall be nailed. The nose of all eave tiles shall be fastened with approved clips. All rake tiles shall be nailed with two 100 >40-60 nails The nose of all ridge, hip and rake tiles shall be set in a bead of roofer’s mastic. The fastening system shall resist the wind forces in CBC Section 110 0-60 1609.5.3. The fastening system shall resist the wind forces in CBC Section 120 0-60 1609.5.3. The fastening system shall resist the wind forces in CBC Section 130 0-60 1609.5.3. The fastening system shall resist the wind forces in CBC Section All >60 1609.5.3.

For SI: one inch = 25.4 mm, one foot = 304.8 mm, one mile per hour = 0.447 m/s, one pound per square foot= 4.882 kg/m2.

a Minimum fastener size. Hot dipped galvanized ring shank or other corrosion-resistant nails not less than No. 11 gage with 5/16-inch head. Fasteners shall be long enough to penetrate into the sheathing 0.75 inch or through the thickness of the sheathing, whichever is less. Attaching wire for clay and concrete tile shall not be smaller than 0.083 inch and shall be copper, brass or stainless steel. b Snow areas. A minimum of two fasteners per tile are required or battens and one fastener. c Roof slopes greater than 24:12. The nose of all tiles shall be securely fastened. d Horizontal battens. Battens shall be not less than one-inch by two-inch nominal. Provisions shall be made for drainage by a minimum of 1/8-inch riser at each nail or by four-foot-long battens with at least a 0.5-inch separation between battens. Horizontal battens are required for slopes over 7:12. e Perimeter fastening areas include three tile courses but not less than 36 inches from either side of hips or ridges and edges of eaves and gable rakes.

(Amended by Ord. No. 187,719, Eff. 1/23/23.)

Section 1511 of the CBC is adopted by reference, except CBC Sections 1512.2.1 and 1512.3 are not adopted and, in lieu, Los Angeles Municipal Code Subsections 91.1512.2.1 and 91.1512.3 are added.

91.1512.2.1. Roof Recover. The installation of a new roof covering over an existing roof covering shall be permitted where any of the following conditions occur:

1. Where the new roof covering is installed in accordance with the roof covering manufacturer’s approved instructions.

2. Complete and separate roofing systems, such as standing-seam metal roof panel systems, that are designed to transmit the roof loads directly to the building’s structural system and that do not rely on existing roofs and roof coverings for support, shall not require the removal of existing roof coverings.

3. The application of a new protective coating over an existing spray polyurethane foam roofing system shall be permitted without tear off of existing roof coverings.

91.1512.3. Roof Recovering. Roof covering may be applied over existing roofing in accordance to Los Angeles Municipal Code Table 1512.1.

TABLE 1512.1

ALLOWABLE REROOFS OVER EXISTING ROOFING

NEW OVERLAY ROOFING

EXISTING ROOFING BUILT UP ASPHALTSHINGLE TILE ROOF METALROOF MODIFIEDBITUMEN SPRAYURETHANEFORMPOLY- NEW OVERLAY ROOFING EXISTING ROOFING BUILT UP ASPHALTSHINGLE TILE ROOF METALROOF MODIFIEDBITUMEN SPRAYURETHANEFORMPOLY- Yes Yes Built Up Yes Yes Yes Yes (2:12) (2.5:12) Yes Asphalt Shingle NP Yes Yes Yes NP (2.5:12) Asphalt over NP Yes Yes Yes Yes NP Asphalt Tile NP NP NP NP NP NP Roof Metal NP NP NP Yes NP NP Roof Yes Modified Yes Yes NP Bitumen Yes Yes (2.5:12)

NP = Not Permitted. Note: (Minimum Roof Slope)