How To Set A Roof Curb

Curb installation should be a part of the roof deck not on top of insulation or roofing materials.

How to set a roof curb.

And in this one sentence lie the benefits and the detriments we face in the roof curb business everyday. The opening through the metal roof was for the intake duct to the a c unit. After the opening was made for the duct work we then placed the curb in position. After leveling the curb we anchored the curb down with 4 screws to the metal sub roof.

Roof curbs are in many cases installed on the roof and temporarily covered over for waterproofing purposes much earlier than the construction schedule requires. Specify prefab roof curbs for use with all roof penetrations and roof mounted equipment including and not limited to hvac units duct openings pipe penetrations power roof exhauster intake and relief vents flues or job fabricated items. Pressure treated nailers should be provided by the curb manufacturer to receive roofing felts and eliminate noise transfer. Prior to setting the unit onto the curb the installer should ensure that a sealing material is positioned between the unit and the curb to provide a watertight connection.

The rooftop unit may be mounted immediately after the curb is installed. Because the roof is slightly slanted one side of the curb had to leveled with boards. The primary function of the curb is to keep weather out while supporting flashing the equipment on it. Curbs should be a minimum of eight inches above the finished roof and factory insulated to reduce condensation.

Roofi ng may be completed after setting the unit.