NO. AB-057 : | |
DATE : | July 19, 2004 (Updated 01/01/2023 for code references.) |
SUBJECT : | Plan Review and Permit Process |
TITLE : | Local Equivalency for Approval of Roof Hatches in Lieu of Stairway Penthouses in Designated Buildings |
PURPOSE : | The purpose of this Administrative Bulletin is to provide standards and procedures for the application, case-by-case review and approval of requests for a modification based on Local Equivalency to allow the use of roof hatches as alternates to stairway penthouses in R-3 buildings where the stairway access to the roof does not strictly comply with the provisions of Section 1011.12 of the San Francisco Building Code. |
REFERENCE : | Current edition of the San Francisco Building Code - Section
and Tables 601 and 602, Fire Resistance of Walls - Section
, Parapets - Section 1011, Stairways - Section 1011.12, Stairway to roof |
DISCUSSION : | The installation of roof penthouses throughout the City is an issue of serious concern to the public and the Planning Department inasmuch as such penthouses may expand structures to larger than may be compatible with surrounding structures and may block sunlight and views. Roof penthouses are often a basis of extensive Planning and Building Department review, permit appeals and reconsideration during construction. The use of roof hatches in lieu of stair penthouses under certain conditions can do much to resolve the problems related to roof penthouses, could permit rapid processing and issuance, and, if installed in accordance with the following conditions, would not impair the code-mandated suitability, strength, effectiveness, fire resistance, durability, safety or sanitation of the standard method of roof access. |
This bulletin does not apply to buildings under the jurisdiction of the San Francisco Fire Department, although requests to apply alternates and equivalencies to the regular code will be considered by the Fire Department on a case-by-case basis.
The use of roof hatches under this Administrative Bulletin is limited to the following applications:
1. Where proposed roof hatches provide access to the roof of buildings under the jurisdiction of the Department of Building Inspection, and
2. Where a stairway to the roof is either required by code or voluntarily proposed, and
3. Where the roof hatch and its appurtenances are approved and constructed as detailed below, and
4. When the roof hatch is served by a stairway.
Other applications for roof hatches in lieu of required fully complying stairways will be considered on a case-by-case basis under the review and approval procedures in the California Building Code regarding “Modifications” and “Alternative materials, alternate designs and methods of construction.”
Note: Under Section 1011.12, Exception: In buildings without an occupied roof, access to the roof shall be permitted to be a roof hatch or trap door not less than16 square feet in area and having a minimum dimension of 2 feet.
Procedure for Application of Local Equivalency
Project sponsors wishing to apply Local Equivalencies must fill out and submit the request for Approval of Local Equivalencies on a standard form (Attachment A). Fees to be paid and scheduling of review of requests are as noted on that form. Following Department of Building Inspection and, as appropriate, other agency review, each request will be approved, approved with conditions, disapproved, or placed on “Hold” pending submittal of additional information.
Further details of procedures for the review of Local Equivalencies and appeal of departmental determinations may be found in AB-005, Procedures for Approval of Local Equivalencies.
Conditions of Local Equivalency
Roof hatches in lieu of stairway penthouses may be permitted when the following approved equivalent provisions are met. This Local Equivalency allows roof hatches to be used in lieu of stairway penthouses and for such roof hatch to be considered as meeting the code requirements for a stairway to the roof if the below listed standard provisions are met:
1. Applicant shall submit drawings showing details of the proposed roof hatch, stairway, stair handrail, and other details as needed to demonstrate compliance, insofar as is practical, with the stairway requirements of the San Francisco Building Code. Submittal documents shall include a plan view showing the location of the roof hatch and stairway and shall include sections and/or elevations detailing the proposed installation.
2. Stairways shall have handrails on at least one side. At least one handrail shall extend at least 34 inches above the roof surface. Such handrail may be attached to the underside of the operable hatch so that it is in the correct position for handrails when the hatch is in the open position, or it may be secured to the roof or other construction. Minor breaks in the continuity of the handrail are permitted; handrail sections must be generally aligned.
3. If the opening for the stairway to the roof is within the distance where protection of openings is required, then parapets extending along the parapet wall at least the length of the opening shall be provided per Section 705.11.
4. The curb at the roof opening for the roof hatch on the side where the stairs emerge from the interior shall extend above the roof surface no more than nine inches, the curb at the roof hatch on other sides of the hatch shall not exceed 24 inches above the roof surface, and the maximum height of any portion of the hatch in a closed position shall not exceed 36 inches above the roof surface.
5. The rise and run of stairs to the roof shall meet regular code requirements.
6. The width of a stairway to a roof and the clear width of a roof hatch in its open position shall be not less than 30 inches, except that when serving an occupied roof with an occupant load of 10 or more or serving an occupied roof area greater than 400 square feet the width shall meet the specific requirements of the San Francisco Building Code. Handrails, lifting mechanisms and other equipment may encroach into the required width up to 1 1/2" when the roof hatch is in a fully open position.
7. When the roof hatch serves an occupied roof, the hatch latching mechanism shall be operable from the exterior.
A permit application and related submittal documents shall detail all construction that is approved as a result of this Request for Approval of Local Equivalency. No work to install roof hatches in lieu of stairway penthouses shall be done prior to approval of such Permit Application and issuance of a permit.
Signed By:
Frank Y. Chiu, July 18, 2004
Director
Department of Building Inspection
Approved by the Building Inspection Commission on July 18, 2004
Attachment A: Procedures for Approval of Local Equivalency