Masonry & Stone

Grounded in the retrieved California Historical Building Code — click a citation to read the verbatim passage:

• CHBC § 8-804 High relevance — show source text

  SECTION 8-804 — ALLOWABLE CONDITIONS FOR SPECIFIC MATERIALS

  Archaic materials which exist and are to remain in qualified historical buildings or structures shall be evaluated for their condition and for loads required by this code. The structural survey required in Section 8-703 of the CHBC shall document existing conditions, reinforcement, anchorage, deterioration and other factors pertinent to establishing allowable stresses, strength levels and adequacy of the archaic materials. The remaining portion of this chapter provides additional specific requirements for commonly encountered archaic materials.

  SECTION 8-805 — MASONRY

  For adobe, see Section 8-806.

  8-805.1 Existing solid masonry. Existing solid masonry walls of any type, except adobe, may be allowed, without testing, a maximum ultimate strength of 9 pounds per square inch (62.1 kPa) in shear where there is a qualifying statement by the architect or engineer that an inspection has been made, that mortar joints are filled and that both brick and mortar are reasonably good. The shear stress above applies to unreinforced masonry, except adobe, where the maximum ratio of unsupported height or length to thickness does not exceed 13, and where minimum quality mortar is used or exists. Wall height or length is measured to supporting or resisting elements that are at least twice as stiff as the tributary wall. Stiffness is based on the gross section. Shear stress may be increased by the addition of 10 percent of the axial direct stress due to the weight of the wall directly above. Higher-quality mortar may provide a greater shear value and shall be tested in accordance with Appendix A, Chapter A1 of the California Existing Building Code (CEBC) 2010 edition, and as modified by the CHBC.

  8-805.2 Stone masonry.

  8-805.2.1 Solid-backed stone masonry. Stone masonry solidly backed with brick masonry shall be treated as solid brick masonry as described in Section 8-805.1 and in the 2009 International Existing Building Code [®] (IEBC [®] ), provided representative testing and inspection verifies solid collar joints between stone and brick and that a reasonable number of stones lap with the brick wythes as headers or that steel anchors are present. Solid stone masonry where the wythes of stone effectively overlap to provide the equivalent header courses may also be treated as solid brick masonry.

  8-805.2.2 Independent wythe stone masonry. Stone masonry with independent face wythes may be treated as solid brick masonry as described in Section 8-805.1 and the CEBC, provided representative testing and inspection verify that the core is essentially solid in the masonry wall and that steel ties are epoxied in drilled holes between outer stone wythes at floors, roof and not to exceed 4 feet (1219 mm) on center in each direction, between floors and roof. A reinforcing element shall exist or be provided at or near the top of all stone masonry walls.

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  ARCHAIC MATERIALS AND METHODS OF CONSTRUCTION

  8-805.2.3 Testing of stone masonry. Testing of stone masonry shall be similar to the 2010 CEBC requirements for brick masonry, except that representative stones which are not interlocked shall be pulled outward from the wall and shear area appropriately calculated after the test.

• CHBC § 8-805.2 Medium relevance — show source text

  8-805.2 Stone masonry.

  8-805.2.1 Solid-backed stone masonry. Stone masonry solidly backed with brick masonry shall be treated as solid brick masonry as described in Section 8-805.1 and in the 2009 International Existing Building Code [®] (IEBC [®] ), provided representative testing and inspection verifies solid collar joints between stone and brick and that a reasonable number of stones lap with the brick wythes as headers or that steel anchors are present. Solid stone masonry where the wythes of stone effectively overlap to provide the equivalent header courses may also be treated as solid brick masonry.

  8-805.2.2 Independent wythe stone masonry. Stone masonry with independent face wythes may be treated as solid brick masonry as described in Section 8-805.1 and the CEBC, provided representative testing and inspection verify that the core is essentially solid in the masonry wall and that steel ties are epoxied in drilled holes between outer stone wythes at floors, roof and not to exceed 4 feet (1219 mm) on center in each direction, between floors and roof. A reinforcing element shall exist or be provided at or near the top of all stone masonry walls.

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  ARCHAIC MATERIALS AND METHODS OF CONSTRUCTION

  8-805.2.3 Testing of stone masonry. Testing of stone masonry shall be similar to the 2010 CEBC requirements for brick masonry, except that representative stones which are not interlocked shall be pulled outward from the wall and shear area appropriately calculated after the test.

  8-805.3 Reconstructed walls. Totally reconstructed walls utilizing original brick or masonry, constructed similar to original, shall be constructed in accordance with the regular code. Repairs or infills may be constructed in a similar manner to the original walls without conforming to the regular code.

  SECTION 8-806 — ADOBE

  8-806.1 General. Unburned clay masonry may be constructed, reconstructed, stabilized or rehabilitated subject to this chapter. Alternative approaches which provide an equivalent or greater level of safety may be used, subject to the concurrence of the enforcing agency.

  8-806.2 Moisture protection. Provisions shall be in place to protect adobe structures from deterioration due to moisture penetration. Adobe shall be maintained in reasonably good condition. Particular attention shall be given to moisture content of adobe walls. Unmaintained walls or ruins shall be evaluated for safety based on their condition and stability. Additional protection measures may be appropriate subject to the concurrence of the enforcing agency.

  8-806.3 Height to thickness ratio. Unreinforced new or existing adobe walls meeting these criteria need not be evaluated for out of plane failure. Where existing dimensions do not meet these conditions, additional strengthening measures, such as a bond beam, may be appropriate. Existing sod or rammed earth walls shall be considered similar to the extent these provisions apply.

  1. One-story adobe load-bearing walls shall not exceed a height-to-thickness ratio of 6.
  2. Two-story adobe buildings or structures’ height- to-thickness wall ratio shall not exceed 6 at the ground floor and 5 at the second floor, and shall be measured at floor-to-floor height when the second floor and attic ceiling/roof are connected to the wall as described below.
• CHBC § 8-801 Medium relevance — show source text

  SECTION 8-801 — PURPOSE, INTENT AND SCOPE

  8-801.1 Purpose. The purpose of the CHBC is to provide regulations for the use of historical methods and materials of construction that are at variance with regular code requirements or are not otherwise codified, in buildings or structures designated as qualified historical buildings or properties. The CHBC require enforcing agencies to accept any reasonably equivalent alternatives to the regular code when dealing with qualified historical buildings or properties.

  8-801.2 Intent. It is the intent of the CHBC to provide for the use of historical methods and materials of construction that are at variance with specific code requirements or are not otherwise codified.

  8-801.3 Scope. Any construction type or material that is, or was, part of the historical fabric of a structure is covered by this chapter. Archaic materials and methods of construction present in a historical structure may remain or be reinstalled or be installed with new materials of the same class to match existing conditions.

  SECTION 8-802 — GENERAL ENGINEERING APPROACHES

  Strength values for archaic materials shall be assigned based upon similar conventional codified materials, or on tests as hereinafter indicated. The archaic materials and methods of construction shall be thoroughly investigated for their details of construction in accordance with Section 8-703. Testing shall be performed when applicable to evaluate existing conditions. The architect or structural engineer in responsible charge of the project shall assign allowable stresses or strength levels to archaic materials. Such assigned strength values shall not be greater than those provided for in the following sections without adequate testing, and shall be subject to the concurrence of the enforcing agency.

  SECTION 8-803 — NONSTRUCTURAL ARCHAIC MATERIALS

  Where nonstructural historical materials exist in uses which do not meet the requirements of the regular code, their continued use is allowed by this code, provided that any public health and life safety hazards are mitigated subject to the concurrence of the enforcing agency.

  SECTION 8-804 — ALLOWABLE CONDITIONS FOR SPECIFIC MATERIALS

  Archaic materials which exist and are to remain in qualified historical buildings or structures shall be evaluated for their condition and for loads required by this code. The structural survey required in Section 8-703 of the CHBC shall document existing conditions, reinforcement, anchorage, deterioration and other factors pertinent to establishing allowable stresses, strength levels and adequacy of the archaic materials. The remaining portion of this chapter provides additional specific requirements for commonly encountered archaic materials.

  SECTION 8-805 — MASONRY

  For adobe, see Section 8-806.

  8-805.1 Existing solid masonry. Existing solid masonry walls of any type, except adobe, may be allowed, without testing, a maximum ultimate strength of 9 pounds per square inch (62.1 kPa) in shear where there is a qualifying statement by the architect or engineer that an inspection has been made, that mortar joints are filled and that both brick and mortar are reasonably good. The shear stress above applies to unreinforced masonry, except adobe, where the maximum ratio of unsupported height or length to thickness does not exceed 13, and where minimum quality mortar is used or exists. Wall height or length is measured to supporting or resisting elements that are at least twice as stiff as the tributary wall. Stiffness is based on the gross section. Shear stress may be increased by the addition of 10 percent of the axial direct stress due to the weight of the wall directly above.

• CHBC § 1.11. Medium relevance — show source text

  Adopting agency	BSC	BSC- CG	SFM	HCD	Col6	Col7	DSA	Col9	Col10	OSHPD	Col12	Col13	Col14	Col15	Col16	Col17	BSCC	DPH	AGR	DWR	CEC	CA	SL	SLC
  Adopting agency	BSC	BSC- CG	SFM	1	2	1/AC	AC	SS	SS/CC	1	1R	2	3	4	5	6	6	6	6	6	6	6	6	6
  Adopt entire chapter								X		X				X
  Adopt entire chapter as amended (amended sections listed below)
  Adopt only those sections that are listed below
  Chapter / Section

  The state agency does not adopt sections identified with the following symbol: The Office of the State Fire Marshal’s adoption of this chapter or individual sections is applicable to structures regulated by other state agencies pursuant to Section 1.11.

  2025 CALIFORNIA BUILDING CODE 21A-1

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  21A-2 2025 CALIFORNIA BUILDING CODE

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  21 A MASONRY

  User notes:

  About this chapter: Chapter 21A provides comprehensive and practical requirements for masonry construction. Chapter 21A is applicable to structures regulated by the Division of the State Architect-Structural Safety—including public elementary and secondary schools, community colleges, and state-owned or state-leased essential services buildings (applications listed in Sections 1.9.2.1

  [DSA-SS] and 1.9.2.2 [DSA-SS/CC])—and by the Department of Health Care Access and Information/Office of Statewide Hospital Planning and Development—including hospitals and correctional treatment centers (applications listed in Sections 1.10.1

  [OSHPD 1] and 1.10.4 [OSHPD 4]).

  SECTION 2101 A —GENERAL

  2101 A .1 Scope. This chapter shall govern the materials, design, construction and quality of masonry.

• CHBC § 1.1 Medium relevance — show source text

  1.1_|||||||||X||X|X|||X|||||||||| |2101.1.2|||||||||X||X|X|||X|||||||||| |2101.1.3|||||||||X||X|X|||X|||||||||| |2101.1.4|||||||||X|||||||||||||||| |2101.1.5|||||||||X|||||||||||||||| |2101.2|||||||||||X|X|||X|||||||||| |2101.2.2|||||||||||X|X|||X|||||||||| |2103.1|||||||||||X|X|||X|||||||||| |2103.4|||||||||||X|X|||X|||||||||| |2103.5|||||||||||X|X|||X|||||||||| |2103.6|||||||||||X|X|||X|||||||||| |2104.2|||||||||||X|X|||X|||||||||| |2104.3|||||||||||X|X|||X|||||||||| |2105.2|||||||||||X|X|||X|||||||||| |2105.3|||||||||||X|X|||X|||||||||| |2105.4|||||||||||X|X|||X|||||||||| |2106.1.1|||||||||||X|X|||X|||||||||| |2106.1.2|||||||||||X|X|||X|||||||||| |2106.1.3|||||||||||X|X|||X|||||||||| |2107.1|||||||||||X|X|||X|||||||||| |2107.5|||||||||||X|X|||X|||||||||| |2109|||||||||||X|X|||X|||||||||| |2109.2.4.8.2|||||||||||||||||||||X|||| |2110.1|||||||||||X|X|||X|||||||||| |2113.9.2|||X|||||||||||||||||||||| |2115|||||||||X||||||||||||||||

  The state agency does not adopt sections identified with the following symbol: The Office of the State Fire Marshal’s adoption of this chapter or individual sections is applicable to structures regulated by other state agencies pursuant to Section 1.11.

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  21-2 2025 CALIFORNIA BUILDING CODE

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  21 MASONRY

  User notes:

  About this chapter: Chapter 21 establishes minimum requirements for masonry construction. The provisions address: material specifications and test methods; types of wall construction; criteria for engineered and empirical designs; and required details of construction, including the execution of construction. The provisions provide a framework for applying applicable standards to the design and construction of masonry structures. Masonry design methodologies including allowable stress design, strength design and empirical design are covered by the provisions of this chapter. Also addressed are masonry fireplaces and chimneys, masonry heaters and glass unit masonry.

  ICC code development note: Code change proposals to this chapter will be considered by the IBC—Structural Code Development Committee during the

  2025 (Group B) Code Development Cycle.

• CHBC § 0.3 Medium relevance — show source text

  [BS] A113.8 Nonstructural masonry walls. Unreinforced masonry walls that do not carry design vertical or lateral loads and that are not required by the design to be part of the lateral force-resisting system shall be adequately anchored to new or existing supporting elements. The anchors and elements shall be designed for the out-of-plane forces specified in the building code. The height- or length-to-thickness ratio between such supporting elements for such walls shall not exceed nine.

  APPENDIX A-16 2025 CALIFORNIA EXISTING BUILDING CODE

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  APPENDIX A—GUIDELINES FOR THE SEISMIC RETROFIT OF EXISTING BUILDINGS

  [BS] A113.9 Truss and beam supports. 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.

  Exception: Secondary supports are not required where S D1 is less than 0.3g.

  [BS] A113.10 Adjacent buildings. Where elements of adjacent buildings do not have a separation of 5 inches (127 mm) or greater, the allowable height-to-thickness ratios for “all other buildings” per Table A110.2 shall be used in the direction of consideration.

  SECTION A114—WALLS OF UNBURNED CLAY, ADOBE OR STONE MASONRY

  [BS] A114.1 General. Walls of unburned clay, adobe or stone masonry construction shall conform to the following:

  1. Walls of unburned clay, adobe or stone masonry shall not exceed a height- or length-to-thickness ratio specified in Table A114.1.

  2. Adobe shall be allowed a maximum value of 9 pounds per square inch (62.1 kPa) for shear unless higher values are justified by test.

  3. Mortar for repointing may be of the same soil composition and stabilization as the brick, in lieu of cement mortar.

  [BS]TABLE A114.1—MAXIMUM HEIGHT-TO-THICKNESS RATIO FOR ADOBE OR STONE WALLS	Col2	Col3	Col4
  	_SD_1	_SD_1	_SD_1
  	0.13g ≤****_SD_1 < 0.25g	0.25g ≤****_SD_1 < 0.4g	_SD_1 ≥ 0.4g
  One-story buildings	12	10	8
  Two-story buildings
  First story	14	11	9
  Second story	12	10	8

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  APPENDIX A-18 2025 CALIFORNIA EXISTING BUILDING CODE

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  CALIFORNIA EXISTING BUILDING CODE – MATRIX ADOPTION TABLE

  APPENDIX A

  CHAPTER A2 – EARTHQUAKE HAZARD REDUCTION IN EXISTING REINFORCED CONCRETE AND REINFORCED MASONRY WALL BUILDINGS WITH FLEXIBLE DIAPHRAGMS

• CHBC § 3.5 Medium relevance — show source text

  Grout pours not terminated at the top of constructed masonry shall comply with TMS 602, Articles 3.5 C.3.a through 3.5 C.3.c. 2. The top of the grout pour shall be in the top course of the constructed masonry. Grout pours not terminated within the top course of the constructed masonry shall comply with TMS 602, Articles 3.5 C.3.a through 3.5 C.3.c. 3. Grout pours in excess of 4 feet (1219 mm) or 5 feet 4 inches (1651 mm) for 10-inch (254 mm) nominal or wider for hollow unit masonry shall be subject to approval of the enforcement agency and the following: a. Grouting shall be done in a continuous pour in lifts not exceeding the requirements of TMS 602, Article 3.5 D. b. The grouting of any section of wall shall be completed in one day with no interruptions greater than one hour. c. Cleanout openings shall be provided at the bottom of each pour of grout.

  TABLE 7—GROUT SPACE REQUIREMENTS	Col2	Col3	Col4
  GROUT TYPE1	MAXIMUM GROUT POUR HEIGHT, FT (M)	MINIMUM CLEAR WIDTH OF GROUT SPACE,2,3 IN. (MM)	MINIMUM CLEAR GROUT SPACE DIMENSIONS **FOR GROUTING CELLS OF HOLLOW UNITS,3 ** IN. × IN. (MM × MM)
  Coarse	1 (0.3)	21/2 (63.5)	2 × 3(50.8× 76.2)
  Coarse	44 (1.22)	21/2 (63.5)	21/2 × 3 (63.5 × 76.2)
  Coarse	12.675 (3.86)	31/2 (88.9)	3 × 35 (76.2 × 76.2)
  1. Coarse grout is defined in ASTM C476. 2. For grouting between masonry wythes. 3. Minimum clear width of grout space and minimum clear grout space dimension are the net dimension of the space determined by subtracting masonry protrusions and the diameters of horizontal reinforcement from the as-built cross section of the grout space. 4. Maximum pour height can be increased to 5.33 feet for 10-inch nominal or wider hollow unit masonry. 5. Maximum pour height can be increased to 16 feet for hollow unit masonry walls with a nominal thickness of 12 inches or more and minimum clear grout space dimensions of 3 in. x 4 in. (76.2 mm x 102 mm).	1. Coarse grout is defined in ASTM C476. 2. For grouting between masonry wythes. 3. Minimum clear width of grout space and minimum clear grout space dimension are the net dimension of the space determined by subtracting masonry protrusions and the diameters of horizontal reinforcement from the as-built cross section of the grout space. 4. Maximum pour height can be increased to 5.33 feet for 10-inch nominal or wider hollow unit masonry. _5.

• CHBC § 8-705.1 Medium relevance — show source text

  8-705.1 Gravity loads. The capacity of the structure to resist gravity loads shall be evaluated and the structure strengthened as necessary. The evaluation shall include all parts of the load path. Where no distress is evident, and a complete load path is present, the structure may be assumed adequate by having withstood the test of time if anticipated dead and live loads will not exceed those historically present.

  8-705.2 Wind and seismic loads. The ability of the structure to resist wind and seismic loads shall be evaluated. Wind loads shall be considered when appropriate, but need not exceed 75 percent of the wind loads prescribed by the regular code. The evaluation shall be based on the requirements of Section 8-706.

  8.705.2.1 Any unsafe conditions in the lateral-load-resisting system shall be corrected, or alternative resistance shall be provided. When strengthening is required, additional resistance shall be provided to meet the minimum requirements of the CHBC. The strengthening measures shall be selected with the intent of meeting the performance objectives set forth in Section 8-701.2. The evaluation of structural members and structural systems for seismic loads shall consider the inelastic performance of structural members and their ability to maintain load-carrying capacity during the seismic loadings prescribed by the regular code.

  8.705.2.2 The architect or engineer shall consider additional measures with minimal loss of, and impact to, historical materials which will reduce damage and needed repairs in future earthquakes to better preserve the historical structure in perpetuity. These additional measures shall be presented to the owner for consideration as part of the rehabilitation or restoration.

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  STRUCTURAL REGULATIONS

  SECTION 8-706 — LATERAL LOAD REGULATIONS

  8-706.1 Seismic forces. Strength-level seismic forces used to evaluate the structure for resistance to seismic loads shall be based on the R -values tabulated in the regular code for similar lateral-force-resisting systems including consideration of the structural detailing of the members where such R -values exist. Where such R -values do not exist, an appropriate R -value shall be rationally assigned considering the structural detailing of the members.

  Exceptions:

  1. The forces need not exceed 0.75 times the seismic forces prescribed by the regular code requirements.
  2. For Risk Category I, II or III structures, near-fault increases in ground motion (maximum considered earthquake ground motion of 0.2 second spectral response greater than 150 percent at 5 percent damping) need not be considered when the fundamental period of the building is 0.5 seconds in the direction under consideration.
  3. For Risk Category I or II structures, the seismic base shear need not exceed 0.30W.
  4. For Risk Category III or IV structures, the seismic base shear need not exceed 0.40W.

  8-706.1.1 When a building is to be strengthened with the addition of a new lateral force resisting system, the R -value of the new system can be used when the new lateral force resisting system resists at least 75 percent of the building’s base shear regardless of its relative rigidity.

  8-706.1.2 Evaluation and seismic improvement of unreinforced masonry bearing wall buildings shall comply with the California Existing Building Code (CEBC), Appendix Chapter A1 2013 Edition, and as modified by the CHBC.

  Exceptions:

• CHBC § 10.6.5 Medium relevance — show source text

  Applies to stone or masonry veneer exceeding the first story height.
  e. The adjustment factor for stone or masonry veneer shall be applied to all exterior braced wall lines and all braced wall lines on the interior of the building, backing or perpen-
  dicular to and laterally supporting veneered walls.
  f. See Section R602.10.6.5 for requirements where stone or masonry veneer does not exceed the first-story height.
  g. One- and two-family dwellings in Seismic Design Category D2 exceeding two stories shall be designed in accordance with accepted engineering practice.|For SI: 1 foot = 304.8 mm, 1 pound per square foot = 0.0479 kPa.
  a. Linear interpolation shall be permitted.
  b. The total length of bracing required for a given wall line is the product of all applicable adjustment factors.
  c. The length-to-width ratio for the floor/roof diaphragm shall not exceed 3:1.
  d. Applies to stone or masonry veneer exceeding the first story height.
  e. The adjustment factor for stone or masonry veneer shall be applied to all exterior braced wall lines and all braced wall lines on the interior of the building, backing or perpen-
  dicular to and laterally supporting veneered walls.
  f. See Section R602.10.6.5 for requirements where stone or masonry veneer does not exceed the first-story height.
  g. One- and two-family dwellings in Seismic Design Category D2 exceeding two stories shall be designed in accordance with accepted engineering practice.|For SI: 1 foot = 304.8 mm, 1 pound per square foot = 0.0479 kPa.
  a. Linear interpolation shall be permitted.
  b. The total length of bracing required for a given wall line is the product of all applicable adjustment factors.
  c. The length-to-width ratio for the floor/roof diaphragm shall not exceed 3:1.
  d. Applies to stone or masonry veneer exceeding the first story height.
  e. The adjustment factor for stone or masonry veneer shall be applied to all exterior braced wall lines and all braced wall lines on the interior of the building, backing or perpen-
  dicular to and laterally supporting veneered walls.
  f. See Section R602.10.6.5 for requirements where stone or masonry veneer does not exceed the first-story height.
  g. One- and two-family dwellings in Seismic Design Category D2 exceeding two stories shall be designed in accordance with accepted engineering practice.|For SI: 1 foot = 304.8 mm, 1 pound per square foot = 0.0479 kPa.
  a. Linear interpolation shall be permitted.
  b. The total length of bracing required for a given wall line is the product of all applicable adjustment factors.
  c. The length-to-width ratio for the floor/roof diaphragm shall not exceed 3:1.
  d. Applies to stone or masonry veneer exceeding the first story height.
  e. The adjustment factor for stone or masonry veneer shall be applied to all exterior braced wall lines and all braced wall lines on the interior of the building, backing or perpen-
  dicular to and laterally supporting veneered walls.
  f. See Section R602.10.6.5 for requirements where stone or masonry veneer does not exceed the first-story height.
  g.

• CHBC § 1.4 Medium relevance — show source text

  The architect or structural engineer shall establish a method of quality control of the masonry construction acceptable to the enforcement agency which shall be described in the contract documents. Verification of compliance with the requirements for the specified strength of masonry during construction shall be provided using the prism test method in accordance with TMS 602, Article 1.4 B.3. Verification of compliance with the specified compressive strength prior to the start of construction shall be obtained by using the prism test method in accordance with TMS 602, Article 1.4 B.3.

  2105.3 Mortar and grout tests. [OSHPD 1R, 2 & 5] TMS 602, Article 1.4 B Compressive strength determination. Modify TMS 602, Arti- cle 1.4 B as follows by adding:

  5. Additional testing requirements: a. At the beginning of all masonry work, at least one test sample of the mortar shall be taken on 3 successive working days and at 1-week intervals thereafter. Where mortar is based on a proportion specification, mortar shall be sampled and tested during construction in accordance with ASTM C780, including Annex 4, to verify the proportions specified in ASTM C270, Table 2. Where mortar is based on a property specification, mortar shall be laboratory prepared and tested prior to construction in accordance with ASTM C780 to verify the properties specified in ASTM C270, Table 1 and field sampled and tested during construction in accordance with ASTM C780 to verify the proportions with the laboratory tests. Mortar sampling and testing is not required for preblended mortars in conformance with ASTM C1714 with a material certificate. b. Samples of grout shall be taken for each mix design, each day grout is placed, and not less than every 5,000 square feet (464.5 m [2] ) of masonry wall area. They shall meet the minimum strength requirement given in ASTM C476/TMS 602 Section 2.2 or greater as specified. c. Additional samples shall be taken whenever any change in materials or job conditions occur, as determined by the building official.

  d. Test specimens for mortar and grout shall be made as set forth in ASTM C780/C1586 and ASTM C1019. When the prism test method is used in accordance with TMS 602, Article 1.4 B.3 during construction, the tests in this section are not required.

  Exception: For nonbearing nonshear masonry walls not exceeding total wall height of 12 feet (3658 mm) above top of foundation, mortar test shall be permitted to be limited to those at the beginning of masonry work for each mix design. 2105.4 Masonry core testing . [OSHPD 1R, 2 & 5] Two cores shall be taken from each building for each 5,000 square feet (465 m [2] ) of the masonry wall area or fraction thereof. The approved agency shall perform or observe the coring of the masonry walls and sample loca- tions shall be subject to approval of the registered design professional.

• CHBC § 8-810 Medium relevance — show source text

  The hand-built, untested use of wrought or black iron, the use of cast iron or grey iron, and the myriad of joining methods that are not specifically allowed by code may be used wherever applicable and wherever they have proven their worth under the considerable span of years involved with most qualified historical buildings or structures. Uplift capacity should be evaluated and strengthened where necessary. Fixed conditions or midheight lateral loads on cast iron columns that could cause failure should be taken into account. Existing structural wrought, forged steel or grey iron may be assigned the maximum working stress prevalent at the time of original construction.

  SECTION 8-810 — HOLLOW CLAY TILE

  The historical performance of hollow clay tile in past earthquakes shall be carefully considered in evaluating walls of hollow clay tile construction. Hollow clay tile bearing walls shall be evaluated and strengthened as appropriate for lateral loads and their ability to maintain support of gravity loads. Suitable protective measures shall be provided to prevent blockage of exit stairways, stairway enclosures, exit ways and public ways as a result of an earthquake.

  SECTION 8-811 — VENEERS

  8-811.1 Terra cotta and stone. Terra cotta, cast stone and natural stone veneers shall be investigated for the presence of suitable anchorage. Steel anchors shall be investigated for deterioration or corrosion. New or supplemental anchorage shall be provided as appropriate.

  8-811.2 Anchorage. Brick veneer with mechanical anchorage at spacings greater than required by the regular code may remain, provided the anchorages have not corroded. Nail strength in withdrawal in wood sheathing may be utilized to its capacity in accordance with code values.

  SECTION 8-812 — GLASS AND GLAZING

  8-812.1 Glazing subject to human impact. Historical glazing material located in areas subject to human impact may be approved subject to the concurrence of the enforcing agency when alternative protective measures are provided. These measures may include, but not be limited to, additional glazing panels, protective film, protective guards or systems, and devices or signs which would provide adequate public safety.

  8-812.2 Glazing in fire-rated systems. See Section 8-402.3.

  TABLE8-8A—STRENGTH VALUES FOR EXISTING MATERIALS	Col2
  EXISTING MATERIALS OR CONFIGURATIONS OF MATERIALS1	STRENGTH LEVEL CAPACITY x14.594 for N/m
  1. Horizontal diaphragms2 1.1. Roofs with straight sheathing and roofing applied directly to the sheathing 1.2. Roofs with diagonal sheathing and roofing applied directly to the sheathing 1.3. Floors with straight tongue-and-groove sheathing 1.4. Floors with straight sheathing and finished wood flooring with board edges offset or perpendicular 1.5. Floors with diagonal sheathing and finished	300 lbs per foot for seismic shear 750 lbs per foot for seismic shear 300 lbs per foot for seismic shear 1,500 lbs per foot for seismic shear 1,800 lbs per foot for seismic shear
  2. Crosswalls2,3 2.1. Plaster on wood or metal lath 2.2. Plaster on gypsum lath 2.3. Gypsum wallboard, unblocked edges 2.4.

• CHBC § 2.3 Medium relevance — show source text

  R606.2.3 AAC masonry. AAC masonry units shall conform to ASTM C1691 and ASTM C1693 for the strength class specified.

  R606.2.4 Stone masonry units. Stone masonry units shall conform to the following standards: ASTM C503 for marble building stone (exterior); ASTM C568M for limestone building stone; ASTM C615 for granite building stone; ASTM C616 for sandstone building stone; or ASTM C629 for slate building stone.

  R606.2.5 Architectural cast stone. Architectural cast stone shall conform to ASTM C1364.

  R606.2.6 Adhered manufactured stone masonry veneer units. Adhered manufactured stone masonry veneer units shall conform to ASTM C1670.

  R606.2.7 Second-hand units. Second-hand masonry units shall not be reused unless they conform to the requirements of new units. The units shall be of whole, sound materials and free from cracks and other defects that will interfere with proper laying or use. Old mortar shall be cleaned from the unit before reuse.

  R606.2.8 Mortar. Except for mortars listed in Sections R606.2.9, R606.2.10 and R606.2.11, mortar for use in masonry construction shall meet the proportion specifications of Table R606.2.8 or the property specifications of ASTM C270. The type of mortar shall be in accordance with Sections R606.2.8.1, R606.2.8.2 and R606.2.8.3.

  2025 CALIFORNIA RESIDENTIAL CODE 6-93

  on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

  WALL CONSTRUCTION

  TABLE R606.2.8—MORTAR PROPORTIONSa, b	Col2	Col3	Col4	Col5	Col6	Col7	Col8	Col9	Col10	Col11
  MORTAR	TYPE	PROPORTIONS BY VOLUME (cementitious materials)	PROPORTIONS BY VOLUME (cementitious materials)	PROPORTIONS BY VOLUME (cementitious materials)	PROPORTIONS BY VOLUME (cementitious materials)	PROPORTIONS BY VOLUME (cementitious materials)	PROPORTIONS BY VOLUME (cementitious materials)	PROPORTIONS BY VOLUME (cementitious materials)	PROPORTIONS BY VOLUME (cementitious materials)
  MORTAR	TYPE	Portland cement or blended cement	Mortar cement	Mortar cement	Mortar cement	Masonry cement	Masonry cement	Masonry cement	**Hydrated limec ** or lime putty	Aggregate ratio **(measured in damp,