Sustainable Roofs

Roofing is usually not one of the first things you think of when making a list of home improvements that could reduce your electricity bills and help improve the environment. However, there are a few sustainable roofing systems that could provide benefits not available from your standard roof. Cool roofs, green roofs and blue roofs can help to mitigate climate change through some unique characteristics.

The City of Miami Beach recently passed the Urban Heat Island Ordinance(2019-4252) which requires new construction to install a sustainable roofing system. Sustainable roofing systems can be solar roofs, blue roofs, cool roofs, green roofs, and other roofing systems that will reduce the heat island effect, allow reuse or retention of stormwater or reduce greenhouse gases.

Cool Roofs

A cool roof is a type of roof that reflects more sunlight and absorbs less heat than a standard roof. This causes the roof to stay cooler and helps to keep the building cooler as well. If you are installing a new roof or completely replacing an existing roof, then a cool roof may be in the same price range as a standard roof. Cool roofs are most beneficial in hot climates.

Benefits of cool roofs:

Lower roof temperature
Extended roof service life
Lower energy bills due to decreased air conditioning needs
When a cluster of buildings have cool roofs, this can help to reduce the heat island effect

Additional information can be found at the following websites:

DOE: Cool Roofs

EPA: Cool Roofs

Blue Roofs

A blue roof is a type of roofing system designed to temporarily store rainwater and control the release of the captured water. Various flow controls can be used to store, block and/or regulate the water. You should verify the load capacity of your existing roof before installing a blue roof. Compared to green roofs, blue roofs are less expensive to install. A few precautions should be taken when installing a blue roof in a climate that attracts mosquitoes including designing for a maximum hold time of 72 hours and monitoring how the blue roof drains after rainfall events.

Benefits of blue roofs:

Rainwater detention
Reduce stormwater runoff
Can be combined with a cool roof to provide a cooling benefit

Additional information can be found at the following websites:

Philadelphia Water Department: Blue Roofs

Massachusetts DEP: Blue Roofs

FDOH: Mosquito-borne diseases

Green Roofs

A green roof is a type of roofing system where a layer of vegetation is planted on a roof along with layers of protective barriers including vapor control, thermal insulation, roofing membrane, root repellant, drainage layer and filter membrane. Depending on the design and loading capacity of your existing roof, additional roof support may be needed. The installation of a green roof costs more than a standard roof but provides many unique benefits.

Benefits of green roofs:

Reduce stormwater runoff
Long lifespan
Lower roof temperature
Lower energy bills due to decreased air conditioning needs
Vegetation provides oxygen and habitat to wildlife

Additional information can be found at the following websites:

NPS: Green Roofs

Green Roofs

Solar Roofs

Solar photovoltaics (PVs) are popular rooftop renewable energy generation systems; especially as prices for the systems have dropped in the past few years as a result of technological advances. Solar PVs, also known as solar panels, are made of semiconductor materials and convert sunlight into electricity. They are commonly installed on rooftops but can also be ground mounted.

Benefits of rooftop solar PVs:

Produce electricity without creating GHG emissions
Reduce your monthly electricity bill
Low maintenance costs compared to other types of renewable energy

Additional information can be found at the following websites:

DOE: Basics of PV Technology

DOE: Planning for PV on your home

EnergySage

Financing

The Property Assessed Clean Energy (PACE) financing platform is available to Miami Beach property owners to finance their sustainable roof projects among other qualifying improvement projects. PACE allows property owners to pay for qualifying improvement projects through property assessments over a set time period instead of with a large up-front payment. This debt is then tied to the property, not the property owner.

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