What Is a Roof Curb
Roof curbs are typically built with wood or metal that extends vertically around an opening in the roof. Roof curbs are most commonly used beneath rooftop equipment such as HVAC units, skylights and roof hatches. By elevating the penetrationComponent - A roof penetration is an opening where something passes through the roof surface, such as a plumbing pipe or an HVAC unit curb. More above the roof surface, the curb creates a vertical surface that can be flashed and waterproofed more reliably than the equipment itself.
While curbs appear on both steep-slope and low-slope roofsRoof Types - Low-slope roofs (flat roofs) are a type of roof system with less than a 3:12 pitch, most commonly found on commercial and industrial buildings. More, they are most common on low-slope commercial roofs where large rooftop equipment must be integrated into the roof systemRoof Types - A roof system (roof assembly) is the entire series of roofing layers and components above the roof deck that work together to weatherproof the building. More.
Because curbs surround large openings in the roof, the flashing protecting them is a common source of leaks. Standing waterRoof Problems - Ponding water is accumulated water that remains on a roof surface for more than 48 hours after rainfall. More or failed flashing at the curb can allow water into the roof system.