CFR›Title 10›Chapter II›Part 434›Subpart D ContainsSections 434.401–434.404CorpusDaily eCFRDisplayed edition2026-05-08Last updated2026-05-08 Subpart D—Building Design Requirements—Electric Systems and Equipment Sections 434.401 § 434.401 Electrical power and lighting systems. 434.402 § 434.402 Building envelope assemblies and materials. 434.403 § 434.403 Building mechanical systems and equipment. 434.404 § 434.404 Building service systems and equipment. Previous C Subpart C—Design Conditions Next E Subpart E—Building Energy Cost Compliance Alternative