Noise from Specific Sources in Nashua, NH (2026)

HVAC & Mechanical Noise

Nashua codifies the only explicit numeric dBA cap in its noise framework for HVAC / mechanical equipment in Chapter 190 (Land Use Code). Mechanical appurtenances (heating and air-conditioning equipment) may be located on the exterior portion of structures, but shall include any necessary sound buffer and/or noise attenuation equipment sufficient to reduce sound levels to 50 decibels daytime (7:00 a.m. - 8:00 p.m.) and 45 decibels nighttime (8:00 p.m. - 7:00 a.m.), measured at residential zoning district boundaries. The Nashua City Planning Board site-plan checklist incorporates this standard.