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   (Amended by Ord. No. 171,175, Eff. 7/25/96.)
91.8810.1.  General.  In addition to the seismic analysis required elsewhere in this division, the licensed engineer or architect responsible for the seismic analysis of the building shall determine and record the information required by this section on the approved plans.
91.8810.2.  Construction Details.  (Amended by Ord. No. 172,592, Eff. 6/28/99, Oper. 7/1/99.)  The following requirements, with appropriate construction details, shall be made part of the approved plans:
   1.   All unreinforced masonry walls shall be anchored at the roof and ceiling levels by tension bolts through the wall as specified in Table No. 88-I, or by an approved equivalent at a maximum anchor spacing of six feet (1829 mm).  Anchors installed in accordance with Section 91.8114 of this Code shall be accepted as conforming to this requirement.
   All unreinforced masonry walls shall be anchored at all floors and ceiling with tension bolts through the wall or by existing rod anchors at a maximum anchor spacing of six feet (1829 mm).  All existing rod anchors shall be secured to the joists to develop the required forces.  The Department may require testing to verify the adequacy of the embedded ends of existing rod anchors.  Tests, when required, shall conform to Section 91.8809.8.
   EXCEPTION:  Walls need not be anchored to ceiling systems that, because of their low mass and/or relative location with respect to the floor or roof systems, would not impose significant normal forces on the wall and cause out-of-plane wall failures.
   At the roof and all floor levels, the anchors nearest the building corners shall be combination shear and tension anchors located not more than two feet (610 mm) horizontally from the inside corners of the walls.
   When access to the exterior face of the masonry wall is prevented by proximity of an existing building, wall anchors conforming to Items 5 and 7 in Table No. 88-I may be used.
   Alternative devices to be used in lieu of tension bolts for masonry wall anchorage shall be tested as specified in Section 91.8809.9.
   2.   Diaphragm chord stresses of horizontal diaphragms shall be developed in existing materials or by addition of new materials.
   3.   Where trusses and beams other than rafters or joists are supported on masonry, independent secondary columns shall be installed to support vertical loads of the roof or floor members.
   4.   (Amended by Ord. No. 179,324, Eff. 12/10/07, Oper. 1/1/08.)  Parapets and exterior wall appendages not capable of resisting the forces specified in this division shall be removed, stabilized or braced to ensure that the parapets and appendages remain in their original position.
   The maximum height of an unbraced, unreinforced masonry parapet above the lower of either the level of tension anchors or roof sheathing shall not exceed one and one half times the thickness of the parapet wall.  If the required parapet height exceeds this maximum height, a bracing system designed for the force factors specified in Table Nos. 88-E and 88-F for walls shall support the top of the parapet.  Parapet corrective work must be performed in conjunction with the installation of tension roof anchors.
   5.   All deteriorated mortar joints in unreinforced masonry walls shall be pointed with Type S or N mortar.  Prior to any pointing, the wall surface must be raked and cleaned to remove loose and deteriorated mortar.  All preparation and pointing shall be done under the continuous inspection of a registered deputy inspector certified to inspect masonry or concrete.  At the conclusion of the project, the inspector shall submit a written report to the Department setting forth the portion of work inspected.
   6.   Repair details of any cracked or damaged unreinforced masonry wall required to resist forces specified in this division.
91.8810.3.  Existing Construction.  The following existing construction information shall be made a part of the approved plans:
   1.   The type and dimensions of existing walls and the size and spacing of floor and roof members.
   2.   The extent and type of existing wall anchorage to floors and roof.
   3.   The extent and type of parapet corrections which were performed in accordance with Section 91.8114 of this Code.
   4.   Accurately dimensioned floor plans and masonry wall elevations showing dimensioned openings, piers, wall thickness and heights, and veneer and anchorages.
   5.   The location of cracks or damaged portions of unreinforced masonry walls requiring repairs.
   6.   The type of interior wall surfaces and ceilings, and if reinstalling or anchoring existing plaster is necessary.
   7.   The general condition of the mortar joints and if the joints need pointing.
   8.   The location of the shear tests shall be shown on the floor plans and building wall elevations, and the complete test report shall be reproduced on the approved plans.