Grade I insulation installation: no gaps, no compression, fully filling cavity, supported aligned with air barrier

Description

ENERGY STAR requires Grade I insulation installation per RESNET ANSI/RESNET/ICC 301 — meaning no voids, no gaps, no compression, complete cavity fill, and direct alignment with the building's air barrier (the layer that stops bulk air movement). Common defects that disqualify: compressed batts behind wiring, gaps at top + bottom plates, batts that don't make contact with the air barrier on all six sides.

Why this exists

Insulation R-value is only effective when installed Grade I — Grade II can lose 20-40% of effective R. Grade I requires careful coordination between the insulator and the air sealing contractor; the architect can support this with detailed wall sections showing where the air barrier transitions through floor systems, etc.

Categories

Source

Solver enforcement

Browsable only — the solver does not currently enforce this directive (no spec-level data to check against). This entry exists so the architect personas can cite it in conversation and the user can read what the rule says.

Related directives

• Continuous load path from roof to foundation · HUD RSDG §2.4
• Residential structural reliability targets 1-in-100 to 1-in-1000 annual probability of failure · HUD RSDG §2.5
• Residential floor live load: 40 psf minimum (30 psf sleeping rooms) · HUD RSDG §3.4
• Wind load design uses ASCE 7 basic wind speed for the locality · HUD RSDG §3.6
• Ground snow load for Virginia: 25 psf eastern, up to 40 psf western mountains · HUD RSDG §3.7