Inverted Attic Bulkhead for HVAC Ductwork: Roseville, California (Fact Sheet)
K. Hovnanian Homes constructed a 2,253-ft single-story slab-on-grade ranch house for an occupied test house (new construction) in Roseville, California. One year of monitoring and analysis focused on the effectiveness of the space conditioning system at maintaining acceptable temperature and relative humidity levels in several rooms of the home, as well as room-to-room differences and the actual measured energy consumption by the space conditioning system. In this home, the air handler unit (AHU) and ducts were relocated to inside the thermal boundary. The AHU was relocated from the attic to a mechanical closet, and the ductwork was located inside an insulated and air-sealed bulkhead in the attic. To describe the performance and comfort in the home, the research team selected representative design days and extreme days from the annual data for analysis. To ensure that temperature differences were within reasonable occupant expectations, the team followed Air Conditioning Contractors of America guidance. At the end of the monitoring period, the occupant of the home had no comfort complaints in the home. Any variance between the modeled heating and cooling energy and the actual amounts used can be attributed to the variance in temperatures at the thermostat versus the modeled inputs.