
NH's New ADU Law (HB 577): What You Can Build in Your Backyard Now
As of July 1, 2025, New Hampshire's HB 577 lets you build an accessory dwelling unit, attached or detached, by right in any single-family zone, up to 950 square feet. Here is exactly what changed, what your town can and cannot require, and what it means for a Southern NH homeowner.
June 11, 2026











