IECC 2021 · Model
Chapter 5: Existing Buildings
44 sections in this chapter of the IECC 2021 model text — not Model's amended edition.
505.1.1 Unconditioned space Any unconditioned or low-energy space that is altered to become a conditioned space shall comply with Section R502.
- 505.1.1Unconditioned space
- C403.5Economizers
- C405.2.5Specific application controls
- C405.2.6Manual controls
- C405.2.7Exterior lighting controls
- C501.1Scope
- C501.1.1Existing buildings
- C501.2Compliance
- C501.3Maintenance
- C501.4New and replacement materials
- C501.5Historic buildings
- C502.1General
- C502.2Change in space conditioning
- C502.3Compliance
- C503.1General
- C503.2Building envelope
- C503.3Heating and cooling systems
- C503.4Service hot water systems
- C503.5Lighting systems
- C504.1General
- C504.2Application
- C505.1General
- R401.1Scope - Residential
- R401.2Application
- R402.1General
- R402.1.2Insulation and fenestration criteria
- R402.4Air leakage
- R402.5Maximum Fenestration U-Factor
- R403.1Controls - Residential Mechanical
- R403.2Hot water boiler temperature reset
- R403.3Duct insulation and sealing - Residential
- R403.5Service hot water systems
- R404.1Lighting equipment
- R501.1Scope
- R501.1.1Existing buildings
- R501.2Compliance
- R501.3Maintenance
- R501.4New and replacement materials
- R501.5Historic buildings
- R502.1General
- R502.2Change in space conditioning
- R502.3Compliance
- R503.1General
- R504.1General
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