IECC 2021 · Model

Chapter C4: Commercial Building Envelope

34 sections in this chapter of the IECC 2021 model text — not Model's amended edition.

C401.3 Thermal envelope certificate A permanent thermal envelope certificate shall be completed by an approved party. Such certificate shall be posted on a wall in the space where the space conditioning equipment is located, a utility room or other approved location. If located on an electrical panel, the certificate shall not cover or obstruct the visibility of the circuit directory label, service disconnect label or other required labels. A copy of the certificate shall also be included in the construction…

  1. C401.3Thermal envelope certificate
  2. C402.1.2Equipment buildings
  3. C402.1.4Assembly U -factor, C -factor or F -factor-based method
  4. C402.2.3Floors
  5. C402.2.4Slabs-on-grade
  6. C402.2.5Below-grade walls
  7. C402.4.5Doors
  8. C403.1.1Calculation of heating and cooling loads
  9. C403.1.2Data centers
  10. C403.10Heat rejection equipment
  11. C403.2.1Zone isolation required
  12. C403.3.2HVAC equipment performance requirements
  13. C403.3.3Hot gas bypass limitation
  14. C403.5.1Integrated economizer control
  15. C403.6.1Variable air volume and multiple-zone systems
  16. C403.7.2Enclosed parking garage ventilation controls
  17. C403.8.1Allowable fan horsepower
  18. C403.8.2Motor nameplate horsepower
  19. C403.9Large-diameter ceiling fans
  20. C404.4Insulation of piping
  21. C404.6Heated-water circulating and temperature maintenance systems
  22. C404.7Drain water heat recovery units
  23. C405.10Voltage drop
  24. C405.11Automatic receptacle control
  25. C405.2.4Daylight-responsive controls
  26. C405.3.1Total connected interior lighting power
  27. C405.3.2Interior lighting power allowance
  28. C405.5Exterior lighting power requirements
  29. C405.6Dwelling electrical meter
  30. C405.7Electrical transformers
  31. C405.8Electric motors
  32. C405.9Vertical and horizontal transportation systems and equipment
  33. C406.1.1Tenant spaces
  34. C406.2More efficient HVAC equipment performance

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