Many Hawaii homes have small attics, open beam construction, or vaulted ceilings where a ducted QuietCool system is impractical. In 2020, with input from Island Cooling, QuietCool Manufacturing developed the Roof Mounted whole house fan (RM4.0). This system is a first of its kind whole house fan mounted on the roof with 4 possible interior applications.
DG1: Homes with open beam construction or direct installation use a 22.5″x22.5″ ceiling damper with louvers that open and close. Can be installed with Plenum (See below)
DG2: In homes with large ceiling beams (2×12), the ceiling bay is used as a plenum to install two 14″x14″ louvered ceiling grills to ventilate two separate areas.
DB: Homes with limited attic space can use a 20″ duct and damper box (DB1430) but bypass the attic for direct ventilation.
PL: An option to install a plenum box for homes with direct installation offsets the intake and RM4.0 for quieter operation. Intake is 22.5″x22.5″ ceiling damper with louvers that open and close. Recommended for open beam homes.