Roof Curbs, Extensions and Equipment Supports August 2008
Page Header Roof Curbs & Extensions Prefabricated roof curbs reduce installation time and costs by ensuring compatibility between the fan, curb and roof opening. A wide variety of roof curbs are available including: flanged, straight-sided, canted, pitched, ridged, vented, and sound-absorbing. Extensions raise the fan discharge and can provide an accessible mounting location for dampers. Insect screen bases and vented extensions are also available.
PageGPI Header Model Standard Construction Features Insulation - Ridged fiberglass insulation is standard on all GPI curbs. The insulation is securely attached at both the top and bottom with an insulation tray so it will not have any exposed ends. Three pound density insulation is available in 1, 11⁄2, and 2‑inch thicknesses. Formed Body Curb Curbs are perfectly formed on three sides and have only one welded seam to ensure a strong square curb.
Page Header Roof Curbs Models GPI, GPIP and GPIR These curbs are designed for roof decks covered with 2 to 6 inches of insulation. Model GPI is for use on flat roofs, GPIP for pitched roofs and GPIR is available for ridged (double pitched) roofs. They are mounted directly to the roof deck before the insulation is applied, then roofed and flashed to the top of the wood nailer for weather tightness.
Page Header Equipment Supports and Curb Extensions Models GESS and GESR These equipment supports are designed for use on both insulated (GESR) and non-insulated (GESS) flat roof decks. They are mounted directly to the deck structure, then roofed and flashed for weather tightness. A variety of sizes and widths are available. (Refer to CAPS for more details.) Models GESS and GESR are available in welded aluminum or galvanized steel. Available in heights of 8, 12 and 14 inches and widths of 4, 6 and 8 inches.
Page SoundHeader Curbs Model AT Sound Curbs are designed to reduce fan generated sound traveling down the ductwork without adversely affecting fan performance. Air passes between the streamlined baffles allowing the fan sound to be absorbed and dissipated within the curb area preventing it from entering the building. Each perforated aluminum baffle section is filled with fiberglass wool. Spring steel wire holding clips secure the aluminum baffle.
Page Header Dimensional Data Fan Curb Adapt Down 1.500 B A A Curb Adapter (Fan curb cap is smaller than existing curb) Basic Adapter and Reducer Dimensional Information Curbs without wood nailers = Adapted curb cap width and length will be 1/2‑inch larger than the curb AD dimension. Curbs with wood nailers = Adapted curb cap width and length will be 11⁄2 inches larger than the curb AD dimensions.
Typical Installation Greenheck's straight-sided roof curbs are designed for general exhaust or supply applications. General Flashed Roof Installation: 1. Remove roofing material where roof penetration is to be made and provide a 10‑inch wide clearance around perimeter of hole in roof. 2. Apply roofing cement around roof opening. 3. Place and center roof curb over hole in roof so it sits on roofing cement.
