Key Facts
| Statutory basis | Adopted by municipalities under MGL c.25A §6 |
|---|---|
| Adopting municipalities (Standard Stretch) | 290+ |
| Specialized Stretch Code (Net Zero) municipalities | 30+ |
| Energy savings vs base 780 CMR | ~12-20% |
| Air infiltration limit | ≤3 ACH50 (vs base 5 ACH50) |
| Wall R-value required | R-21 cavity + R-5 continuous (climate zone 5) |
| Ceiling R-value | R-49 attic / R-30 cathedral |
| Window U-factor max | 0.27 (vs 0.32 base) |
| Window SHGC max (south) | 0.40 |
| Net Zero deadline (Specialized) | 2030 |
| Solar PV-ready | Required in Specialized Stretch Code |
| EV charger-ready | Required in Specialized Stretch Code |
Related Sub-Entities
- Standard Stretch Code — Baseline stretch — 290+ municipalities
- Specialized Stretch Code — Net Zero variant — 30+ municipalities
- 780 CMR (Massachusetts State Building Code) — Statewide minimum
- ASHRAE 90.1 — National commercial reference
Programs — Related Pro Build Services
- Custom Home Builders — Stretch code-compliant new construction.
- Air Sealing — Meeting ≤3 ACH50 stretch code limit.
- ENERGY STAR Windows — Stretch code U-factor compliance.