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Chapter 24 — GLASS AND GLAZING

Section 2411 — [OSHPD 1, 1R, 2, 4 & 5]

California Building Code (Title 24, Part 2) · 2019 edition · updated 2026-09-12 · California

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

THERMAL BARRIERS IN ALUMINUM MULLION SYSTEMS

2411.1 General.

The requirements of this section address the use of thermal barriers composite in aluminum mullion sys- tems. The thermal barriers shall consist of either poured and debridged or mechanically locked pre-formed construction. The thermal barrier systems used shall be those tested and complying with AAMA TIR-A8. The thermal barrier manufac- turer, formulation number or insulating strut size/material and aluminum extrusions shall be consistent between testing, design and construction.

Exception: Single-story Type V skilled nursing or interme- diate care facilities utilizing wood-frame or light-steel- frame construction.

2411.1.1 Structural Design. Structural design of thermal barrier mullions shall satisfy the following requirements:

1. The allowable design stresses for thermal barrier materials composite with aluminum extrusions shall be determined by AAMA TIR-A8 testing for in-plane shear, tension and eccentric load at a minimum of ambient and high temperature using a factor of safety determined by AAMA TIR-A8 Section 6.7. 2. The shear modulus, Gc, of the thermal barrier in similar composite aluminum extrusions shall be determined by AAMA TIR-A8 testing for flexure in AAMA TIR-A8 Section 7.2 at a minimum of ambient and high temperature.

3. The aluminum extrusions used to determine allow- able stresses in the thermal barriers and the shear modulus, Gc, shall be from a specific aluminum extrusion manufacturer and the aluminum sections used in the project. The similarity of the composite aluminum extrusions shall be subject to approval by the building official.

4. The effective moment of inertia of the in-plane com- posite thermal barrier-aluminum section used in flexural design, based upon the tested Gc, shall not exceed 85 percent of the moment of inertia of the combined unbridged aluminum portions of the com- posite section, unless substantiated and approved by the building official.

5. A high temperature of not less than 120°F shall be used for composite section flexure design for wind pressure where the historical high temperature exceeds 100°F. The minimum high temperature for in-plane shear, tension and eccentric load thermal barrier design shall be determined by AAMA TIR- A8 Section 6.5.

6. The lowest allowable stress value and shear modu- lus, Gc, from the ambient and high temperature test- ing shall be used for design.

7. Structural analysis and design for loads on pour and debridged thermal barriers with skip-debridging that has not been tested under AAMA TIR-A8 with skip-debridged test specimens for the specific actions or load direction shall be based upon the relative stiffness between the remaining aluminum bridge and the thermal barrier material and size.

8. Reactions on supporting thermal barrier mullions where the thermal barrier resists the concentrated load, the load shall not be assumed to be distributed over a length greater than 12 inches (305 mm) on the supporting mullion.

9. Mechanically locked, preformed thermal barriers shall be designed and used in pairs.

2411.1.2 Testing and Inspection. Testing and Inspection of thermal barrier mullions shall satisfy the following requirements:

1. Thermal barrier material properties shall be tested in accordance with AAMA TIR-A8 Section 6.1 by the manufacturer. All other testing shall done by an approved testing laboratory or agency.

2. Testing shall include AAMA TIR-A8 Section 7.2 for the flexural tests using the composite section under ambient and high temperature. Thermocouples shall be placed on the outside and interior surfaces and in the middle of the thermal barrier for high tempera- ture testing. Test cycles shall be in accordance with AAMA TIR-A8 Section 7.2.3.

3. Testing shall include AAMA TIR-A8 Section 7.3 for in-plane shear, tension and eccentric load using the composite section under ambient and high tempera- ture.

4. The flexural test for the composite section shall include a span length of 12 feet (3660 mm). The maximum P load in the test shall generate close to a L/175 deflection, where L is the span length, center to center of supports, but shall not exceed the allow- able design stresses for the aluminum composite section in meeting that deflection. Permanent deflec- tion shall not exceed the requirement in AAMA TIR- A8 Section 7.2.2.5.

5. A minimum of two different simple span lengths shall be used to determine Gc under the flexural test. The span lengths tested shall include a short span.

6. The shear modulus, Gc, of the thermal barrier shall be determined using the lowest average Iet from the flexural testing for each composite aluminum extru- sion, temperature and span length tested.

7. Each different composite aluminum extrusion in the project shall be tested to the requirements of AAMA TIR-A8. The magnitude of eccentricity of load on the thermal barrier shall be considered in selecting composite aluminum extrusions for testing.

8. The applicability of existing AAMA TIR-A8 testing of thermal barrier mullions that satisfy the require- ments of this section shall be permitted, in lieu of

390 2019 CALIFORNIA BUILDING 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

GLASS AND GLAZING

project-specific tests, when approved by the building official.

9. Periodic special inspection to ensure compliance with the AAMA TIR-A8 processing for the thermal isolator material shall be performed. Inspections shall include tests of thermal barrier material prop- erties per the manufacturer’s recommendation and AAMA TIR-A8 Section 6.1 and composite perfor- mance requirements per AAMA TIR-A8 Sections 7.2 and 7.3.

10. Periodic special inspection of pour and debridge thermal barrier shall include:

a. Verification that the thermal barrier formula-

tion being used matches that in the design and construction documents.

b. Verification that poured wet or dry shrinkage

as set forth in AAMA TIR-A8 Section 4.1.3.1 does not occur.

c. Proper adhesion of poured thermal barrier

material per AAMA TIR-A8 Section 4.2.1.

d. Confirmation of proper manufacturing pro-

cess per the manufacturer’s recommenda- tions and AAMA TIR-A8 Section 4.3.

e. Inspection of fabrication and handling prac-

tices in accordance with AAMA TIR-A8 Sec- tions 4.3 and 4.4.

f. Testing for thermal barrier material proper-

ties per the manufacturer’s recommendation and AAMA TIR-A8 Section 6.1.

g. Periodic special inspection of the removal of

the temporary thermal bridge shall be provided to ensure that no thermal barrier material is removed in the process.

11. Periodic special inspection of mechanically locked, preformed thermal barriers shall include:

a. Verification that the insulating struts being

used match those in the design and construc- tion documents.

b. Verification that the mechanical lock cavity

distortion and locking distortion does not exist as set forth in AAMA TIR-A8 Sections 4.1.3.3 and 4.1.3.4.

c. Verification of proper knurling of the alumi-

num and crimping of the insulating struts per AAMA TIR-A8 Section 4.2.2.

d. Confirmation of proper manufacturing pro-

cess per the manufacturer’s recommenda- tions and AAMA TIR-A8 Section 4.5.

e. Inspection of fabrication and handling prac-

tices in accordance with AAMA TIR-A8 Sec- tions 4.5 and 4.6.

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

392 2019 CALIFORNIA BUILDING 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 BUILDING CODE – MATRIX ADOPTION TABLE

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▸Contents — California Building Code (Title 24, Part 2)
California Building Code (Title 24, Part 2)
  1. Chapter 2 — DEFINITIONS AND ABBREVIATIONS
  2. Appendix G — FLOOD-RESISTANT
  3. Appendix L — EARTHQUAKE RECORDING
  4. Appendix M — TSUNAMI-GENERATED
  5. Chapter 1 — SCOPE AND ADMINISTRATION
  6. Chapter 3 — OCCUPANCY CLASSIFICATION AND USE
  7. Chapter 4 — SPECIAL DETAILED REQUIREMENTS BASED
  8. Chapter 5 — GENERAL BUILDING HEIGHTS AND AREAS
  9. Chapter 6 — TYPES OF CONSTRUCTION
  10. Chapter 7 — FIRE AND SMOKE PROTECTION FEATURES
  11. Chapter 7A — MATERIALS AND CONSTRUCTION
  12. Chapter 8 — INTERIOR FINISHES
  13. Chapter 9 — FIRE PROTECTION AND LIFE SAFETY SYSTEMS
  14. Chapter 10 — MEANS OF EGRESS
  15. Chapter 11A — HOUSING ACCESSIBILITY
  16. Chapter 11B — ACCESSIBILITY TO PUBLIC BUILDINGS, PUBLIC ACCOMM…
  17. Chapter 12 — INTERIOR ENVIRONMENT
  18. Chapter 14 — EXTERIOR WALLS
  19. Chapter 15 — ROOF ASSEMBLIES AND ROOFTOP STRUCTURES
  20. Chapter 16 — STRUCTURAL DESIGN
  21. Chapter 16A — STRUCTURAL DESIGN
  22. Chapter 17 — SPECIAL INSPECTIONS AND TESTS
  23. Chapter 18 — SOILS AND FOUNDATIONS
  24. Chapter 19 — CONCRETE
  25. Chapter 20 — ALUMINUM
  26. Chapter 21 — MASONRY
  27. Chapter 22 — STEEL
  28. Chapter 23 — WOOD
  29. ▸Chapter 24 — GLASS AND GLAZING
    Overview
    1. Section 2401
    2. Section 2402
    3. Section 2403
    4. Section 2404
    5. Section 2405
    6. Section 2406
    7. Section 2407
    8. Section 2408
    9. Section 2409
    10. Section 2410
    11. Section 2411 — [OSHPD 1, 1R, 2, 4 & 5]
  30. Chapter 25 — GYPSUM BOARD, GYPSUM PANEL PRODUCTS AND PLASTER
  31. Chapter 26 — PLASTIC
  32. Chapter 27 — ELECTRICAL
  33. Chapter 28 — MECHANICAL SYSTEMS
  34. Chapter 30 — ELEVATORS AND CONVEYING SYSTEMS
  35. Chapter 31 — SPECIAL CONSTRUCTION
  36. Chapter 31B — PUBLIC POOLS
  37. Chapter 31C — RADIATION
  38. Chapter 31D — FOOD ESTABLISHMENTS
  39. Chapter 31F — MARINE OIL TERMINALS
  40. Chapter 32 — ENCROACHMENTS INTO THE PUBLIC RIGHT-OF-WAY
  41. Chapter 33 — SAFEGUARDS DURING CONSTRUCTION
  42. Chapter 35 — REFERENCED STANDARDS
  43. Appendix A — EMPLOYEE QUALIFICATIONS
  44. Appendix B — BOARD OF APPEALS
  45. Appendix C — GROUP U – AGRICULTURAL BUILDINGS
  46. Appendix D — FIRE DISTRICTS
  47. Appendix F — RODENTPROOFING
  48. Appendix H — SIGNS
  49. Appendix I — PATIO COVERS
  50. Appendix J — GRADING
  51. Appendix K — GROUP R-3 AND GROUP R-3.1 OCCUPANCIES
  52. Appendix N — REPLICABLE BUILDINGS
  53. Appendix O — EMERGENCY HOUSING

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