1603A Construction Documents — 2025 California Building Code

1603 A .1 General. Construction documents shall show the material, size, section and relative locations of structural members with floor levels, column centers and offsets dimensioned. The design loads and other information pertinent to the structural design required by Sections 1603 A .1.1 through 1603 A .1.10 shall be indicated on the construction documents.

Exception: Construction documents for buildings constructed in accordance with the conventional light-frame construction provisions of Section 2308 shall indicate the following structural design information:

1. Floor and roof dead and live loads.

2. Ground snow load, p g, and allowable stress design ground snow load, p g(asd) .

3. Basic wind speed, V, mph (m/s), and allowable stress design wind speed, V asd , as determined in accordance with Section 1609 A .3.1 and wind exposure.

4. Seismic design category and site class.

5. Flood design data, if located in flood hazard areas established in Section 1612 A .3.

6. Design load-bearing values of soils.

7. Rain load data.

[DSA-SS] Additional requirements are included in Section 4-210 and 4-317 of the California Administrative Code (Part 1, Title 24, C.C.R).

[OSHPD 1] Additional requirements are included in Section 7-115 and 7-125 of the California Administrative Code.

1603 A .1.1 Floor live load. The uniformly distributed, concentrated and impact floor live load used in the design shall be indicated for floor areas. Use of live load reduction in accordance with Section 1607 A .13 shall be indicated for each type of live load used in the design.

1603 A .1.2 Roof live load. The roof live load used in the design shall be indicated for roof areas. 1603 A .1.3 Roof snow load data. The ground snow load, p g, shall be indicated. In areas where the ground snow load, p g , exceeds 15 pounds per square foot (psf) (0.72 kN/m [2] ), the following additional information shall also be provided, regardless of whether snow loads govern the design of the roof:

1. Flat-roof snow load, p f .
2. Snow exposure factor, C e .
3. Risk category.
4. Thermal factor, C t .
5. Slope factor(s), C s .
6. Drift surcharge load(s), p d , where the sum of p d and p f exceeds 30 psf (1.44 kN/m [2] ) .
7. Width of snow drift(s), w .
8. Winter wind parameter for snow drift, W 2 .

1603 A .1.4 Wind and tornado design data. The following information related to wind loads and, where required by Section 1609 A .5, tornado loads shall be shown, regardless of whether wind or tornado loads govern the design of the lateral force-resisting system of the structure:

1. Basic wind speed, V, mph (m/s), tornado speed, V T, mph (m/s), and allowable stress design wind speed, V asd, mph (m/s), as determined in accordance with Section 1609 A .3.1.

2. Risk category.

3. Effective plan area, A e, for tornado design in accordance with Chapter 32 of ASCE 7.

4. Wind exposure. Applicable wind direction if more than one wind exposure is utilized.

5. Applicable internal pressure coefficients, and applicable tornado internal pressure coefficients.

6. Design wind pressures and their applicable zones with dimensions to be used for exterior component and cladding materials not specifically designed by the registered design professional responsible for the design of the structure, pounds per square foot (kN/m [2] ). Where design for tornado loads is required, the design pressures shown shall be the maximum of wind or tornado pressures.

1603 A .1.5 Earthquake design data. The following information related to seismic loads shall be shown, regardless of whether seismic loads govern the design of the lateral force-resisting system of the structure:

1. Risk category.

2. Seismic importance factor, I e .

3. Spectral response acceleration parameters, S S and S 1 .

4. Site class.

5. Design spectral response acceleration parameters, S DS and S D 1 .

6. Seismic design category.

7. Basic seismic force-resisting system(s).

8. Design base shear(s).

9. Seismic response coefficient(s), CS .

10. Response modification coefficient(s), R .

11. Analysis procedure used. 12. Applicable horizontal structural irregularities. 13. Applicable vertical structural irregularities. 14. Location of base as defined in ASCE 7, Section 11.2.

1603A.1.5.1 Connections. Connections that resist design seismic forces shall be designed and detailed on the design drawings.

1603 A .1.6 Geotechnical information. The design load-bearing values of soils shall be shown on the construction documents.

1603 A .1.7 Flood design data. For buildings located in whole or in part in flood hazard areas as established in Section 1612 A .3, the documentation pertaining to design, if required in Section 1612 A .4, shall be included and the following information, referenced to the datum on the community’s Flood Insurance Rate Map (FIRM), shall be shown, regardless of whether flood loads govern the design of the building:

1. Flood design class assigned according to ASCE 24.
2. In flood hazard areas other than coastal high hazard areas or coastal A zones, the elevation of the proposed lowest floor, including the basement.
3. In flood hazard areas other than coastal high hazard areas or coastal A zones, the elevation to which any nonresidential building will be dry floodproofed.
4. In coastal high hazard areas and coastal A zones, the proposed elevation of the bottom of the lowest horizontal structural member of the lowest floor, including the basement.

1603 A .1.8 Special loads. Special loads that are applicable to the design of the building, structure or portions thereof, including but not limited to the loads of machinery or equipment, and that are greater than specified floor and roof loads shall be specified by their descriptions and locations.

1603 A .1.8.1 Photovoltaic panel systems. The dead load of rooftop-mounted photovoltaic panel systems, including rack support systems, shall be indicated on the construction documents.

1603 A .1.9 Roof rain load data. Design rainfall intensity, i (in/hr) (cm/hr), and roof drain, scupper and overflow locations shall be shown regardless of whether rain loads govern the design.

1603A.1.10 Construction procedures. Where unusual erection or construction procedures are considered essential by the Registered Design Professional (RDP) in order to accomplish the intent of the design or influence the construction, such procedure shall be indi- cated on the construction documents.

Geotechnical and geohazard reports for review by the enforcement agency shall be accompanied by a description of the project prepared by the registered design professional (RDP) in responsible charge, which shall include the following: 1. Type of service such as general acute care facility, central utility plants, K-12 school, community college, essential services, etc. 2. Construction materials used for the project such as steel, concrete. masonry, wood, etc. 3. Type of construction project such as new, addition, alteration, repair, etc. 4. For existing buildings, extent of construction such as incidental, minor, major and/or voluntary seismic improvements as defined in Section 318, Part 10, Title 24, CCR [DSA-SS] Section 202 and California Existing Building Code Section 202A [OSHPD 1] .

5. Seismic force resisting system used for each structure in the project. 6. Foundation system that will be used for each structure in the project such as spread footing, drilled piers, etc. 7. Analysis procedure used and basis of design such as ASCE 7 Equivalent Lateral Force Procedure, ASCE 41 Nonlinear Dynamic Procedure, etc.

8. Building characteristics such as number of stories above and below grade, foot print area at grade, grade slope on site, etc. 9. Special features such as requirement for shoring, underpinning, retaining walls, etc.

The application for the approval of construction documents that involves structural elements or components shall be accompanied by complete and accurate structural design computations, which shall comply with requirements prescribed by the enforcement agency: 1. The computations shall be preceded by a detailed index. 2. The computations including each major subsection shall be prefaced by a statement clearly and concisely outlining the basis for the structural design and indicating the manner in which the structure will resist the vertical loads and lateral forces. 3. The computations shall be sufficiently complete to the extent that calculations for the individual structural members and connections can be readily interpreted.