Sub-sections in this division:
Air Sealing — Blower Door Test Required
Residential units in Climate Zone 3 must achieve 3.0 ACH50 via third-party blower door test. Alternatives: 4.0 ACH50 non-sprinklered, 4.5 ACH50 sprinklered. Qualifying air barriers include: 1/2 in gypsum board, 5/8 in Portland cement stucco, closed-cell spray foam (1.5 in min), and others per IECC C402.6.2.3.1.
IECC R402 / C402 (Climate Zone 3)
Energy Efficiency — Insulation Minimums (Climate Zone 3)
Ceiling: R-38. Wood-framed wall: R-20 or R-13+5ci or 0+15ci. Floor: R-19 or R-13+5ci or 15ci. Unheated slab edge: none required. Vertical fenestration: max U-factor 0.30, max SHGC 0.25. Skylight: max U-factor 0.53, max SHGC 0.28.
IECC 2024 Tables R402.1.2 and R402.1.3 (Climate Zone 3)
Foundation Waterproofing & Dampproofing
Section R406.2 (foundation waterproofing and dampproofing) is specifically amended for Southern Nevada conditions. When basements are installed, plans must show a cross-section with materials, exterior waterproofing, and egress window well details.
SNBO 2024 IRC Amendment §R406.2; IRC R406