Department of Building Inspection

DATE:

February 10, 2004 (Tuesday)

TIME:

9:00 a.m. to 11:00 a.m.

LOCATION:

1660 Mission Street, Room 2031

This Subcommittee meets regularly on the first Wednesday of each month at 130 Sutter Street, Room 600. (AIA Office).  If you wish to be placed on a mailing list for agendas, please call (415) 558-6205.

Note:  

Public comment is welcome and will be heard during each agenda item.  Reference documents relating to agenda are available for review at the 1650 Mission Street, Suite 302.  For information, please call David Leung at (415) 558-6033.

Present

Excused

Absent

Ned Fennie, A.I.A.

Jim Guthrie, S.E.

Michael Fretz, S.E.

Other Present

Hanson Tom, DBI
Yan Yan Chew, DBI
Dennis Dang, DBI
David Leung, DBI
Pat Buscovich, S.E.

1.0

Call to Order and Roll Call
Members: Jim Guthrie, S.E.; Chair; Ned Fennie, AIA; Michael Fretz, S.E.

Meeting was called to order at 9:00 a.m. Quorum established with 2 members present.  Michael Fretz was the acting Chair.

2.0

Approval of the minutes of the Structural Subcommittee special meeting of December 10, 2003.

A motion to approve the minutes.   Seconded and approved.

3.0

Continue discussion and possible action on Special inspection requirements for signs and awnings.

The current code section 1701.1 says that “the building official may waive the requirement for the employment of a special inspector if the construction is of a minor nature”. 

Guidelines for waiving special inspection on awnings are discussed. For smaller awnings consisting of EMT (Electrical metallic tubing), structural calculations may not be required.

Code ruling no. BC-302(b)-1 dated 8/20/84 on “Signature On Plans”:
EXEMPT STATUS:-   The following types of applications are classed as exempt and any person may prepare and sign the drawings:
…………….
3. Awnings and Canopies meeting the criteria of 4506 and 4508 respectively.
4. Projecting signs not over 24 square feet in area.  All wall signs.
……………..
SFBC(1984) Section 4506: Awnings

(a)

Definition. For the purpose of this section:
AWNING is a temporary shelter supported entirely from the exterior wall of a building.

(b)

Construction. Awnings shall have noncombustible frames but may have combustible coverings. Every awning shall be collapsible, retractible or capable of being folded against the face of the supporting building. When collapsed, retracted or folded, the design shall be such that the awning does not block any required exit.   

Exception: A fixed awning not more than 10 feet in length may be erected over a doorway to the building.

The total length of all awnings erected on a street face of a building above the second floor shall not exceed 50 percent of the length of the wall upon which they are erected.
Awnings and similar decorations installed inside a building shall comply with the requirements of Chapter 42.

(c)

Projection. Awnings may extend over public property not more than 7 feet from the face of a supporting building but no portion shall extend nearer than 2 feet to the face of the nearest curb line measured horizontally. In no case shall the awning extend over public property greater than two-thirds of the distance from the property line to the nearest curb in front of the building site.

(d)

Clearence. All portions of any awning shall be at least 8 feet above any public walkway.

Exception: Any valance attached to an awning shall not project above the roof of the awning at the point of attachment and shall not extend more than 12 inches below the roof of the awning at the point of attachment, but in no case shall any portion of a valance be less than 7 feet in height above a public way.

(e)

Operating Equipment.   Operating equipment of movable awnings must be so designed that the awning may be retracted, folded or collapsed against the face of the exterior walls without the use of scaffolding or ladders, and such equipment shall not project more than 6 inches beyond the exterior wall of the building.

SFBC(1984) Section 4508.   Canopies:
As used in this Section, a canopy shall be a light structure supported on the building and on columns, or wholly on columns, and used for protection from rain and sun. Canopies shall be allowed only over entrance doorways and only for Occupancy Groups A, B, Division 2 and R.  Canopies may be constructed as awnings and with the same limitations except that
1. The maximum width shall be 10 feet; and
2. The maximum extension over public sidewalk may be a point 2 feet from the curb; and
3. The column support shall be located in the outer one-third of the sidewalk.

For awnings and canopies designed per code(as above), engineering calculations and special inspection on welding will be waived, but not special inspection on anchor bolts.

For awnings and canopies designed per code, special inspection on anchor bolts will be waived if: 
(1) All bolts are torque tested per ICBO report, and
(2) Minimum size of bolts is ½ inches in diameter with minimum embedment of 4 inches, and
(3) For masonry, use only epoxy bolts. No expansion anchors allowed in masonry. Both epoxy and expansion bolts are acceptable in concrete.

For signs weighing not over 250 lbs. and   not over 24 sq. ft. in area and not over 4 feet projection, engineering calculations and all special inspection will be waived, provided that all bolts are torque tested per ICBO report.

For signs not over 24 sq. ft. in area, engineering calculations and special inspection on welding will be waived.

For signs not over 24 sq. ft. in area, special inspection on anchor bolts will be waived if:
(1) structural calculations are submitted showing that the stress level is not more than 25% of the design allowables, and
(2) All bolts are torque tested per ICBO report, and
(3) Minimum size of bolts is ½ inches in diameter with minimum embedment of 4 inches, and
(4) For masonry, use only epoxy bolts. No expansion anchors allowed in masonry. Both epoxy and expansion bolts are acceptable in concrete.

4.0

Continue discussion on update to Structural Standards in 2001 California Building Standards Code.

Proposed change in Section 1629.4.2.1…….
3.   Except in single-story structures, Group R, Division 3 and Group U, Division 1 Occupancies, moment frame systems designated as part of the lateral-force-resisting system shall be special moment-resisting frames.

………………

Hanson Tom has concerns on above change, in that a special (not ordinary) moment resisting frame is required. Consider the case of a shear wall wood building with a frame for open garage.   Extensive ductility need to be put into the connections for the special moment frame. Testing per AISC or prequalified joints may also be  required. The cost is huge and may  be  unreasonable for the wood building, since the frames are designed per drift and not per stress.

Further discussion would be required.

5.0

Continue discussion and possible action on preliminary results of CAPSS program.

Seismic triggers (Flow Chart) including defining the substantial interior remodel   and partial voluntary seismic retrofit (say 20%, similar to ADA Compliance) are discussed.

6.0

Continue discussion on DBI requirements for geotechnical reports.

No discussion.

7.0

Subcommittee Member’s and Staff’s identification of new agenda items, as well as current agenda items to be continued to another subcommittee regular meeting or special meeting.  Subcommittee discussion and possible action regarding administrative issues related to building codes.

Current items 3.0 thru 6.0 will be continued in the next meeting.

New agenda item “Discussion and possible action regarding structural attachments of rooftop solar system” (including criteria for waiving engineering calculation) will be added.

8.0

Public Comment: Public comment will be heard on items not on this agenda but within the jurisdiction of the Code Advisory Committee.  Comment time is limited to 3 minutes per person or at the call of the Chair.

No public comment.

9.0

Adjournment.

The meeting was adjourned at 10:45 a.m.