Custom Coastal Home, Nahant, MA
An oceanfront custom home conditioned by two gas furnaces — one in the attic, one in the basement — engineered from a full Manual J calculation so every floor holds setpoint against coastal wind, with an ERV providing balanced fresh air.
The Project
This custom home on Pleasant Street in Nahant sits directly exposed to ocean wind on Boston's North Shore. Large homes with complex floor plans are difficult to condition evenly from a single air handler: duct runs get long, static pressure climbs, and the rooms farthest from the equipment never quite reach setpoint. Coastal wind loading on the envelope makes the problem worse.
The System
AirPrime's Manual J load calculation split the home into two zones served by two separate gas furnaces — one air handler in the attic serving the upper floor, one in the basement serving the main level. Splitting the load keeps every duct run short, airflow balanced, and both floors at temperature even during winter storms. An ERV supplies continuous balanced fresh air, recovering heat from exhaust air so ventilation does not become a heating penalty.
Delivered
- Room-by-room Manual J load calculation for a wind-exposed coastal envelope
- Two gas furnaces: attic air handler (upper floor) + basement air handler (main level)
- Ductwork designed to Manual D with short, balanced runs on each system
- ERV for balanced, heat-recovering ventilation
- Commissioning with verified airflow on both systems
