How To Set A Roof Curb

After leveling the curb we anchored the curb down with 4 screws to the metal sub roof.

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. Prefabricated roof curbs have been in use since the roof has been utilized for something other than keeping weather out. Pressure treated nailers should be provided by the curb manufacturer to receive roofing felts and eliminate noise transfer.

Because the roof is slightly slanted one side of the curb had to leveled with boards. Curb installation should be a part of the roof deck not on top of insulation or roofing materials. Roof curbs are in many cases installed on the roof and temporarily covered over for waterproofing purposes much earlier than the construction schedule requires. Curbs should be a minimum of eight inches above the finished roof and factory insulated to reduce condensation.

Specify prefabricated roof curbs and related products by a roof curb manufacturer not with or by the equipment manufacturer. 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. After the opening was made for the duct work we then placed the curb in position.

The primary function of the curb is to keep weather out while supporting flashing the equipment on it.