Blue Roof

Blue roofs are non-vegetated systems that hold stormwater. They can be designed as modular trays with loose stones, specialized permeable pavers, or just a waterproof membrane.
Benefits include:

• Better temperature regulation on the roof surface
• Lower building heating and cooling costs
• Minimizes land used for stormwater management, allowing for more recreational and public space area

Blue Roof with Pedestal Pavers Image Credit: Hydropavers, Inc., 2018

Considerations:

• Blue roofs are only suitable for flat roofs.
• Blue roofs can be modified onto existing roofs.
• Rooftops must be evaluated for structural considerations before a blue roof can be installed.

Cost: Blue roofs are generally less costly than green roofs due to the lack of soil and vegetation components. Blue roofs can reduce the size of downstream BMPs, saving cost throughout the stormwater design. No excavation or earthwork is required.

Maintenance: Regular maintenance activities include inspections, debris/ sediment removal, and breaking up ice in winter months.

Deconstructed Blue Roof
Image Credit: Hudson Roofing, 2018