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 As a co ve red en tit y unde r Ti tle II of the Am eri ca ns wi th Di sa bil itie s Ac t, the Ci ty of Los An ge les does no t dis cr im ina te on the basis of dis ab ilit y and, upon req uest , wi ll prov ide

reasonable accom modation to ensure equal acc ess to its programs, services and activities. For efficient handling of information internally and in the internet, conversion to this new

format of code related and adm inistrative information bulletins including MGD and RGA that were previously issued will also allow flexibility and timely distribution of information to

the public.

Page 1 of 2

INFORMATION BULLETIN / PUBLIC - BUILDING CODEREFERENCE NO.: LAMC 91.1609.1.1.3 Effective: 01-01-2014

DOCUMENT NO.: P/BC 2014-016 Revised:Previously Issued As: P/BC 2008-016

DWELLINGS IN HIGH WIND VELOCITY AREAS (HWA)

The “High Wind Velocity” areas are designated to be all of the territory in the City of Los Angeles lying

1. Northeast of San Fernando Road and north of Roscoe Boulevard extended easterly fromSan Fernando Road to City limits.

2. Northerly of Chatsworth Drive from the San Diego Freeway easterly to the Los Angeles-San Fernando City limit.

3. Northerly of Devonshire Street from the San Diego Freeway westerly to the City limit.

4. Northerly of Plummer Street from Topanga Canyon Boulevard westerly to the City limit.

5. Westerly of Valley Circle Boulevard from Plummer Street to Roscoe Boulevard andextended southerly to Stagg Street; Brackenridge Street southwesterly to Valley CircleBoulevard; Valley Circle Boulevard to the Ventura Freeway.

 All dwellings and accessory buildings (including attached patio covers and sun shelters) that areconstructed in a “High Wind Velocity” area shall comply with the provisions of this Information Bulletinin addition to the applicable requirements of the code.

A. Post and Beam Anchorage:

 All roof beams and supporting posts shall be anchored to provide resistance against uplift. Postsshall be anchored to the footings or under-floor construction. All anchorage shall not be less thanone 3/4" diameter thru bolt with 1/4" thick steel side plate on each side, or 7/8" diameter lagscrew, minimum 3 ½” spacing between center line of front and back lag screw, with 1/4" thick steeside plate on each side.

EXCEPTION: Other types of anchorage may be used, provided design computations arefurnished for a wind pressure in an upward direction per ASCE 7, Section 27.4 or Section 28.4at basic wind speed, V = 110 mph.

B. Cantilever Overhangs:

Cantilever overhangs exceeding six feet shall be designed for a wind pressure of 54 pounds per

square foot acting in an upward direction. (ASCE 7 Figure 30.5-1)

C. Roofing:

1. Besides required fasteners per Section 1507.2.6 and Section 1507.7.3.1, asphalt and slateshingles shall be bonded to the underlay with a one-inch diameter spot of asphalt cementunder each tab or by using a 1/8-inch diameter minimum bead of asphalt cement. The

8/16/2019 Dwellings in High Wind Velocity Areas (Hwa) Ib p Bc2014 016

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  P/BC-2014-016 

 As a co ve red en tit y unde r Ti tle II of the Am eri ca ns wi th Di sa bil itie s Ac t, the Ci ty of Los An ge les does no t dis cr im ina te on the basis of dis ab ilit y and, upon req uest , wi ll prov ide

reasonable accom modation to ensure equal acc ess to its programs, services and activities. For efficient handling of information internally and in the internet, conversion to this new

format of code related and adm inistrative information bulletins including MGD and RGA that were previously issued will also allow flexibility and timely distribution of information to

the public.

Page 2 of 2

asphalt cement shall be of a type approved by the Superintendent of Building.

EXCEPTION: Bonding by asphalt cement will not be required for self-sealing shingleswhich bear the Underwriter’s Laboratories, Inc. label for wind-resistant shingles.

2. Tile roofs shall have all boundary tile attached with either 11-gage nails or approved tiesBoundaries include all eaves, hips, ridges, and gable rakes. In addition to the nails or tiessuch boundary tile shall be attached at the exposed end to the next tile below or to thewood support with a continuous bead of roofer’s mastic. Every field tile shall be attachedwith tile attachment per Table 1507.3.7 or other approved devices.

For a mission type tile, cement mortar may be substituted in lieu of roofer’s mastic for tile-to-tile connection, provided the tiles are saturated prior to installation. Barge and rake tileshall be attached with a minimum of two nails. Open ends of eave tile shall be filled witheither a birdstop or mortar. If mortar is used, it shall be applied to saturated tile.