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Chapter 6 — WALL CONSTRUCTION

Section R610

California Residential Code (Title 24, Part 2.5) · 2019 edition · updated 2026-09-12 · California

Italicized text is a California amendment to the model code, as printed in the official publication.

STRUCTURAL INSULATED PANEL WALL CONSTRUCTION

R610.1 General.

Structural insulated panel (SIP) walls shall be designed in accordance with the provisions of this section. Where the provisions of this section are used to design structural insulated panel walls, project drawings, typical details and specifications shall not exempt construction documents from the requirement to be stamped by a California licensed architect or engineer. Notwithstanding other sections of law, the law establishing these provisions is found in Business and Professions Code Sections 5537.1 and 6737.1.

R610.2 Applicability limits.

The provisions of this section shall control the construction of exterior structural insulated panel walls and interior load-bearing structural insulated panel walls for buildings not greater than 60 feet (18 288 mm) in length perpendicular to the joist or truss span, not greater than 40 feet (12 192 mm) in width parallel to the joist or truss span and not greater than two stories in height with each wall not greater than 10 feet (3048 mm) high. Exterior walls installed in accordance with the provisions of this section shall be considered as load-bearing walls. Structural insulated panel walls constructed in accordance with the provisions of this section shall be limited to sites where the ultimate design wind speed ( Vult ) is not greater than 155 miles per hour (69 m/s) in Exposure B or 140 miles per hour (63 m/s) in Exposure C, the ground snow load is not greater than 70 pounds per square foot (3.35 kPa), and the seismic design category is A, B or C.

R610.3 Materials.

SIPs shall comply with the requirements of ANSI/APA PRS 610.1.

R610.3.1 Lumber. The minimum lumber framing material used for SIPs prescribed in this document is NLGA graded No. 2 Spruce-pine-fir. Substitution of other wood species/grades that meet or exceed the mechanical properties and specific gravity of No. 2 Spruce-pine-fir shall be permitted.

R610.3.2 SIP screws. Screws used for the erection of SIPs as specified in Section R610.5 shall be fabricated from steel, shall be provided by the SIP manufacturer and shall be sized to penetrate the wood member to which the assembly is being attached by not less than 1 inch (25 mm). The screws shall be corrosion resistant and have a minimum shank diameter of 0.188 inch (4.7 mm) and a minimum head diameter of 0.620 inch (15.5 mm).

R610.3.3 Nails. Nails specified in Section R610 shall be common or galvanized box unless otherwise stated.

R610.4 SIP wall panels.

SIPs shall comply with Figure R610.4 and shall have minimum panel thickness in accordance with Tables R610.5(1) and R610.5(2) for above-grade walls. SIPs shall be identified by grade mark or certificate of inspection issued by an approved agency in accordance with ANSI/APA PRS 610.1.

(HCD 1 and HCD 2) Note: See the California Factory-Built Housing Law, Health and Safety Code Section 19960 et seq.; and the California Code of Regulations, Title 25, Division 1, Chapter 3; which require building components as addressed in the definition of “factory-built housing” to bear insignia of

406 2019 CALIFORNIA RESIDENTIAL CODE

Copyright © 2019 ICC. ALL RIGHTS RESERVED. Accessed by Kevin Day (kevin.day@dgs.ca.gov), (California Building Standards Commission) Order Number #100735044 on Jul 24, 2019 03:54 PM (PDT) pursuant to License Agreement with ICC. No further reproduction or distribution authorized. Single user only, copying and networking prohibited. ANY UNAUTHORIZED REPRODUCTION OR DISTRIBUTION IS A VIOLATION OF THE FEDERAL COPYRIGHT ACT AND THE LICENSE AGREEMENT, AND SUBJECT TO CIVIL AND CRIMINAL PENALTIES THEREUNDER.

100735044

WALL CONSTRUCTION

R610.5.3 Panel-to-panel connection. SIPs shall be connected at vertical in-plane joints in accordance with Figure R610.8 or by other approved methods.

R610.5.4 Corner framing. Corner framing of SIP walls shall be constructed in accordance with Figure R610.5.4.

R610.5.5 Wall bracing. SIP walls shall be braced in accordance with Section R602.10. SIP walls shall be considered continuous wood structural panel sheathing (bracing Method CS-WSP) for purposes of computing required bracing. SIP walls shall meet the requirements of Section R602.10.4.2 except that SIP corners shall be fabricated as shown in Figure R610.8. Where SIP walls are used for wall bracing, the SIP bottom plate shall be attached to wood framing below in accordance with Table R602.3(1).

R610.5.6 Thermal barrier. SIP walls shall be separated from the interior of a building by an approved thermal barrier in accordance with Section R316.4.

R610.6 Interior load-bearing walls.

Interior load-bearing walls shall be constructed as specified for exterior walls.

R610.7 Drilling and notching.

The maximum vertical chase penetration in SIPs shall have a maximum side dimension of 2 inches (51 mm) centered in the panel. Vertical chases shall have a minimum spacing of 24 inches (610 mm) on center. Not more than two horizontal chases shall be permitted in each wall panel, one at 14 inches (360 mm) plus or minus 2 inches (51 mm) from the bottom of the panel and one at 48 inches (1220 mm) plus or minus 2 inches (51 mm) from the bottom edge of the SIP’s panel. Additional penetrations are permitted where justified by analysis.

R610.8 Headers.

SIP headers shall be designed and constructed in accordance with Table R610.8 and Figure R610.5.1. SIP headers shall be continuous sections without splines. Headers shall be not less than 117/8 inches (302 mm) deep. Headers longer than 4 feet (1219 mm) shall be constructed in accordance with Section R602.7. The strength axis of the factors on the header shall be oriented horizontally.

R610.8.1 Wood structural panel box headers. Wood structural panel box headers shall be allowed where SIP headers are not applicable. Wood structural panel box headers shall be constructed in accordance with Figure R602.7.3 and Table R602.7.3.

approval issued by the Department of Housing and Commu- nity Development, as specified.

R610.5 Wall construction.

Exterior walls of SIP construction shall be designed and constructed in accordance with the provisions of this section and Tables R610.5(1) and R610.5(2) and Figures R610.5(1) through R610.5(5). SIP walls shall be fastened to other wood building components in accordance with Tables R602.3(1) through R602.3(4).

Framing shall be attached in accordance with Table R602.3(1) unless otherwise provided for in Section R610.

R610.5.1 Top plate connection. SIP walls shall be capped with a double top plate installed to provide overlapping at corner, intersections and splines in accordance with Figure R610.5.1. The double top plates shall be made up of a single 2-by (nominal 2-inch) top plate having a width equal to the width of the panel core, and shall be recessed into the SIP below. Over this top plate a cap plate shall be placed. The cap plate width shall match the SIP thickness and overlap the facers on both sides of the panel. End joints in top plates shall be offset not less than 24 inches (610 mm).

R610.5.2 Bottom (sole) plate connection. SIP walls shall have full bearing on a sole plate having a width equal to the nominal width of the foam core. Where SIP walls are supported directly on continuous foundations, the wall wood sill plate shall be anchored to the foundation in accordance with Figure R610.5.2 and Section R403.1.

Copyright © 2019 ICC. ALL RIGHTS RESERVED. Accessed by Kevin Day (kevin.day@dgs.ca.gov), (California Building Standards Commission) Order Number #100735044 on Jul 24, 2019 03:54 PM (PDT) pursuant to License Agreement with ICC. No further reproduction or distribution authorized. Single user only, copying and networking prohibited. ANY UNAUTHORIZED REPRODUCTION OR DISTRIBUTION IS A VIOLATION OF THE FEDERAL COPYRIGHT ACT AND THE LICENSE AGREEMENT, AND SUBJECT TO CIVIL AND CRIMINAL PENALTIES THEREUNDER.

100735044

WALL CONSTRUCTION

TABLE R610.5(1) MINIMUM THICKNESS FOR SIP WALL SUPPORTING SIP OR LIGHT-FRAME ROOF ONLY (inches)a
BUILDING WIDTH (ft) BUILDING WIDTH (ft) BUILDING WIDTH (ft) BUILDING WIDTH (ft) BUILDING WIDTH (ft) BUILDING WIDTH (ft) BUILDING WIDTH (ft) BUILDING WIDTH (ft) BUILDING WIDTH (ft) BUILDING WIDTH (ft) BUILDING WIDTH (ft) BUILDING WIDTH (ft) BUILDING WIDTH (ft) BUILDING WIDTH (ft) BUILDING WIDTH (ft) BUILDING WIDTH (ft) BUILDING WIDTH (ft) BUILDING WIDTH (ft)
ULTIMATE DESIGN
WIND SPEED
Vult(mph)		 ULTIMATE DESIGN
WIND SPEED
Vult(mph)		 SNOW
LOAD
(psf)		 24 24 24 28 28 28 32 32 32 36 36 36 40 40 40
Exp. B Exp. C Exp. C Wall Height (feet) Wall Height (feet) Wall Height (feet) Wall Height (feet) Wall Height (feet) Wall Height (feet) Wall Height (feet) Wall Height (feet) Wall Height (feet) Wall Height (feet) Wall Height (feet) Wall Height (feet) Wall Height (feet) Wall Height (feet) Wall Height (feet)
Exp. B Exp. C Exp. C 8 9 10 8 9 ** 10** 8 9 10 8 9 10 8 9 10
110 — 20 4.5 4.5 4.5 4.5 4.5 4.5 4.5 4.5 4.5 4.5 4.5 4.5 4.5 4.5 4.5
110 — 30 4.5 4.5 4.5 4.5 4.5 4.5 4.5 4.5 4.5 4.5 4.5 4.5 4.5 4.5 4.5
110 — 50 4.5 4.5 4.5 4.5 4.5 4.5 4.5 4.5 4.5 4.5 4.5 4.5 4.5 4.5 4.5
110 — 70 4.5 4.5 4.5 4.5 4.5 4.5 4.5 4.5 4.5 4.5 4.5 6.5 4.5 4.5 6.5
115 — 20 4.5 4.5 4.5 4.5 4.5 4.5 4.5 4.5 4.5 4.5 4.5 4.5 4.5 4.5 4.5
115 — 30 4.5 4.5 4.5 4.5 4.5 4.5 4.5 4.5 4.5 4.5 4.5 4.5 4.5 4.5 4.5
115 — 50 4.5 4.5 4.5 4.5 4.5 4.5 4.5 4.5 4.5 4.5 4.5 4.5 4.5 4.5 6.5
115 — 70 4.5 4.5 4.5 4.5 4.5 4.5 4.5 4.5 6.5 4.5 4.5 DR 4.5 4.5 DR
130 110 20 4.5 4.5 6.5 4.5 4.5 6.5 4.5 4.5 6.5 4.5 4.5 DR 4.5 4.5 DR
130 110 30 4.5 4.5 6.5 4.5 4.5 6.5 4.5 4.5 DR 4.5 4.5 DR 4.5 4.5 DR
130 110 50 4.5 4.5 DR 4.5 4.5 DR 4.5 4.5 DR 4.5 6.5 DR 4.5 DR DR
130 110 70 4.5 4.5 DR 4.5 DR DR 4.5 DR DR 4.5 DR DR DR DR DR
140 120 20 4.5 6.5 DR 4.5 6.5 DR 4.5 DR DR 4.5 DR DR 4.5 DR DR
140 120 30 4.5 6.5 DR 4.5 DR DR 4.5 DR DR 4.5 DR DR 4.5 DR DR
140 120 50 4.5 DR DR 4.5 DR DR DR DR DR DR DR DR DR DR DR
140 120 70 4.5 DR DR DR DR DR DR DR DR DR DR DR DR DR DR

For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 pound per square foot = 0.0479 kPa, 1 mile per hour = 0.447 m/s.

DR = Design Required. a. Design assumptions:

Maximum deflection criteria: L /240.

Maximum roof dead load: 10 psf.

Maximum roof live load: 70 psf.

Maximum ceiling dead load: 5 psf.

Maximum ceiling live load: 20 psf.

Wind loads based on Table R301.2 (2).

Strength axis of facing material applied vertically.

408 2019 CALIFORNIA RESIDENTIAL CODE

Copyright © 2019 ICC. ALL RIGHTS RESERVED. Accessed by Kevin Day (kevin.day@dgs.ca.gov), (California Building Standards Commission) Order Number #100735044 on Jul 24, 2019 03:54 PM (PDT) pursuant to License Agreement with ICC. No further reproduction or distribution authorized. Single user only, copying and networking prohibited. ANY UNAUTHORIZED REPRODUCTION OR DISTRIBUTION IS A VIOLATION OF THE FEDERAL COPYRIGHT ACT AND THE LICENSE AGREEMENT, AND SUBJECT TO CIVIL AND CRIMINAL PENALTIES THEREUNDER.

100735044

WALL CONSTRUCTION

TABLE R610.5(2) MINIMUM THICKNESS FOR SIP WALL SUPPORTING SIP OR LIGHT-FRAME ONE STORY AND ROOF ONLY (inches)a
BUILDING WIDTH (ft) BUILDING WIDTH (ft) BUILDING WIDTH (ft) BUILDING WIDTH (ft) BUILDING WIDTH (ft) BUILDING WIDTH (ft) BUILDING WIDTH (ft) BUILDING WIDTH (ft) BUILDING WIDTH (ft) BUILDING WIDTH (ft) BUILDING WIDTH (ft) BUILDING WIDTH (ft) BUILDING WIDTH (ft) BUILDING WIDTH (ft) BUILDING WIDTH (ft) BUILDING WIDTH (ft) BUILDING WIDTH (ft) BUILDING WIDTH (ft)
ULTIMATE DESIGN
WIND SPEED
Vult (mph)		 ULTIMATE DESIGN
WIND SPEED
Vult (mph)		 SNOW
LOAD
(psf)		 24 24 24 28 28 28 32 32 32 36 36 36 40 40 40
Exp. B Exp. C Exp. C Wall Height (feet) Wall Height (feet) Wall Height (feet) Wall Height (feet) Wall Height (feet) Wall Height (feet) Wall Height (feet) Wall Height (feet) Wall Height (feet) Wall Height (feet) Wall Height (feet) Wall Height (feet) Wall Height (feet) Wall Height (feet) Wall Height (feet)
Exp. B Exp. C Exp. C 8 9 10 8 9 10 8 9 10 8 9 10 8 9 10
110 — 20 4.5 4.5 4.5 4.5 4.5 4.5 4.5 4.5 6.5 4.5 4.5 DR 4.5 4.5 DR
110 — 30 4.5 4.5 4.5 4.5 4.5 4.5 4.5 4.5 6.5 4.5 4.5 DR 4.5 6.5 DR
110 — 50 4.5 4.5 4.5 4.5 4.5 6.5 4.5 4.5 DR 4.5 DR DR DR DR DR
110 — 70 4.5 4.5 6.5 4.5 4.5 DR 4.5 DR DR DR DR DR DR DR DR
115 — 20 4.5 4.5 4.5 4.5 4.5 6.5 4.5 4.5 DR 4.5 4.5 DR 4.5 DR DR
115 — 30 4.5 4.5 4.5 4.5 4.5 6.5 4.5 4.5 DR 4.5 6.5 DR 4.5 DR DR
115 — 50 4.5 4.5 6.5 4.5 4.5 DR 4.5 DR DR 4.5 DR DR DR DR DR
115 — 70 4.5 4.5 DR 4.5 DR DR DR DR DR DR DR DR DR DR DR
120 — 20 4.5 4.5 6.5 4.5 4.5 DR 4.5 4.5 DR 4.5 DR DR 4.5 DR DR
120 — 30 4.5 4.5 DR 4.5 4.5 DR 4.5 6.5 DR 4.5 DR DR DR DR DR
120 — 50 4.5 4.5 DR 4.5 DR DR 4.5 DR DR DR DR DR DR DR DR
120 — 70 4.5 DR DR 4.5 DR DR DR DR DR DR DR DR DR DR DR
130 110 20 4.5 6.5 DR 4.5 DR DR 4.5 DR DR DR DR DR DR DR DR
130 110 30 4.5 DR DR 4.5 DR DR DR DR DR DR DR DR DR DR DR
130 110 50 4.5 DR DR DR DR DR DR DR DR DR DR DR DR DR DR
130 110 70 DR DR DR DR DR DR DR DR DR DR DR DR DR DR DR

For SI: 1 Inch = 25.4 mm, 1 foot = 304.8 mm, 1 pound per square foot = 0.0479 kPa, 1 mile per hour = 0.447 m/s. DR = Design Required. a. Design assumptions:

Maximum deflection criteria: L /240.

Maximum roof dead load: 10 psf.

Maximum roof live load: 70 psf.

Maximum ceiling dead load: 5 psf.

Maximum ceiling live load: 20 psf.

Maximum second-floor dead load: 10 psf.

Maximum second-floor live load: 30 psf.

Maximum second-floor dead load from walls: 10 psf.

Maximum first-floor dead load: 10 psf.

Maximum first-floor live load: 40 psf.

Wind loads based on Table R301.2 (2).

Strength axis of facing material applied vertically.

Copyright © 2019 ICC. ALL RIGHTS RESERVED. Accessed by Kevin Day (kevin.day@dgs.ca.gov), (California Building Standards Commission) Order Number #100735044 on Jul 24, 2019 03:54 PM (PDT) pursuant to License Agreement with ICC. No further reproduction or distribution authorized. Single user only, copying and networking prohibited. ANY UNAUTHORIZED REPRODUCTION OR DISTRIBUTION IS A VIOLATION OF THE FEDERAL COPYRIGHT ACT AND THE LICENSE AGREEMENT, AND SUBJECT TO CIVIL AND CRIMINAL PENALTIES THEREUNDER.

100735044

WALL CONSTRUCTION

410 2019 CALIFORNIA RESIDENTIAL CODE

Copyright © 2019 ICC. ALL RIGHTS RESERVED. Accessed by Kevin Day (kevin.day@dgs.ca.gov), (California Building Standards Commission) Order Number #100735044 on Jul 24, 2019 03:54 PM (PDT) pursuant to License Agreement with ICC. No further reproduction or distribution authorized. Single user only, copying and networking prohibited. ANY UNAUTHORIZED REPRODUCTION OR DISTRIBUTION IS A VIOLATION OF THE FEDERAL COPYRIGHT ACT AND THE LICENSE AGREEMENT, AND SUBJECT TO CIVIL AND CRIMINAL PENALTIES THEREUNDER.

100735044

WALL CONSTRUCTION

Copyright © 2019 ICC. ALL RIGHTS RESERVED. Accessed by Kevin Day (kevin.day@dgs.ca.gov), (California Building Standards Commission) Order Number #100735044 on Jul 24, 2019 03:54 PM (PDT) pursuant to License Agreement with ICC. No further reproduction or distribution authorized. Single user only, copying and networking prohibited. ANY UNAUTHORIZED REPRODUCTION OR DISTRIBUTION IS A VIOLATION OF THE FEDERAL COPYRIGHT ACT AND THE LICENSE AGREEMENT, AND SUBJECT TO CIVIL AND CRIMINAL PENALTIES THEREUNDER.

100735044

WALL CONSTRUCTION

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412 2019 CALIFORNIA RESIDENTIAL CODE

Copyright © 2019 ICC. ALL RIGHTS RESERVED. Accessed by Kevin Day (kevin.day@dgs.ca.gov), (California Building Standards Commission) Order Number #100735044 on Jul 24, 2019 03:54 PM (PDT) pursuant to License Agreement with ICC. No further reproduction or distribution authorized. Single user only, copying and networking prohibited. ANY UNAUTHORIZED REPRODUCTION OR DISTRIBUTION IS A VIOLATION OF THE FEDERAL COPYRIGHT ACT AND THE LICENSE AGREEMENT, AND SUBJECT TO CIVIL AND CRIMINAL PENALTIES THEREUNDER.

100735044

WALL CONSTRUCTION

Copyright © 2019 ICC. ALL RIGHTS RESERVED. Accessed by Kevin Day (kevin.day@dgs.ca.gov), (California Building Standards Commission) Order Number #100735044 on Jul 24, 2019 03:54 PM (PDT) pursuant to License Agreement with ICC. No further reproduction or distribution authorized. Single user only, copying and networking prohibited. ANY UNAUTHORIZED REPRODUCTION OR DISTRIBUTION IS A VIOLATION OF THE FEDERAL COPYRIGHT ACT AND THE LICENSE AGREEMENT, AND SUBJECT TO CIVIL AND CRIMINAL PENALTIES THEREUNDER.

100735044

WALL CONSTRUCTION

TABLE R610.8 MAXIMUM SPANS FOR 11 7 /8-INCH OR DEEPER SIP HEADERS (feet) a, c, d

LOAD CONDITION SNOW LOAD (psf) BUILDINGb
width (feet)
24 28 32 36 40
LOAD CONDITION SNOW LOAD (psf) BUILDINGb
width (feet)
24
28
32
36
40		 28 32 36 40
Supporting roof only 20 4 4 4 4 2
Supporting roof only 30 4 4 4 2 2
Supporting roof only 50 2 2 2 2 2
Supporting roof only 70 2 2 2 DR DR
Supporting roof and one-story 20 2 2 DR DR DR
Supporting roof and one-story 30 2 2 DR DR DR
Supporting roof and one-story 50 2 DR DR DR DR
Supporting roof and one-story 70 DR DR DR DR DR

For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 pound per square foot = 0.0479 kPa. DR = Design Required. a. Design assumptions:

Maximum deflection criterion: L /240. Maximum roof dead load: 10 psf. Maximum ceiling load: 5 psf. Maximum ceiling live load: 20 psf Maximum second-floor live load: 30 psf. Maximum second-floor dead load: 10 psf. Maximum second-floor dead load from walls: 10 psf. Maximum first floor dead load: 10 psf. Wind loads based on Table R301.2(2). Strength axis of facing material applied horizontally. b. Building width is in the direction of horizontal framing members supported by the header. c. The table provides for roof slopes between 3:12 and 12:12. d. The maximum roof overhang is 24 inches (610 mm).

414 2019 CALIFORNIA RESIDENTIAL CODE

Copyright © 2019 ICC. ALL RIGHTS RESERVED. Accessed by Kevin Day (kevin.day@dgs.ca.gov), (California Building Standards Commission) Order Number #100735044 on Jul 24, 2019 03:54 PM (PDT) pursuant to License Agreement with ICC. No further reproduction or distribution authorized. Single user only, copying and networking prohibited. ANY UNAUTHORIZED REPRODUCTION OR DISTRIBUTION IS A VIOLATION OF THE FEDERAL COPYRIGHT ACT AND THE LICENSE AGREEMENT, AND SUBJECT TO CIVIL AND CRIMINAL PENALTIES THEREUNDER.

100735044

CALIFORNIA RESIDENTIAL CODE – MATRIX ADOPTION TABLE

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▸Contents — California Residential Code (Title 24, Part 2.5)
California Residential Code (Title 24, Part 2.5)
  1. Chapter 2 — DEFINITIONS AND ABBREVIATIONS
  2. Chapter 1 — SCOPE AND APPLICATION
  3. Chapter 3 — BUILDING PLANNING
  4. Chapter 4 — FOUNDATIONS
  5. Chapter 5 — FLOORS
  6. ▸Chapter 6 — WALL CONSTRUCTION
    Overview
    1. Section R601
    2. Section R602
    3. Section R603
    4. Section R604
    5. Section R605
    6. Section R606
    7. Section R607
    8. Section R608
    9. Section R609
    10. Section R610
  7. Chapter 7 — WALL COVERING
  8. Chapter 8 — ROOF-CEILING CONSTRUCTION
  9. Chapter 9 — ROOF ASSEMBLIES
  10. Chapter 10 — CHIMNEYS AND FIREPLACES
  11. Chapter 44 — REFERENCED STANDARDS
  12. Appendix F — RADON CONTROL METHODS
  13. Appendix H — PATIO COVERS
  14. Appendix I — PRIVATE SEWAGE DISPOSAL
  15. Appendix J — EXISTING BUILDINGS AND STRUCTURES
  16. Appendix K — SOUND TRANSMISSION
  17. Appendix L — PERMIT FEES
  18. Appendix O — AUTOMATIC VEHICULAR GATES
  19. Appendix Q — TINY HOUSES
  20. Appendix R — LIGHT STRAW-CLAY CONSTRUCTION
  21. Appendix S — STRAWBALE CONSTRUCTION
  22. Appendix T — SOLAR-READY PROVISIONS—DETACHED ONE- AND
  23. Appendix V — SWIMMING POOL SAFETY ACT
  24. Appendix W — AREAS PROTECTED BY THE FACILITIES
  25. Appendix X — EMERGENCY HOUSING

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