Why composites: the composite sunshades were part of a combined renovation and addition to an existing building in San Francisco. Weight is a critical concern in the city due to earthquake codes. The airfoil-shaped fins were impossible or cost-prohibitive to produce with other materials, such as metal or GFRC. This high-rise application required the façade assembly to pass the NFPA 285 fire test.
The sunshades were light enough to comply with earthquake codes, which would not have been feasible with other materials.
Cost
Other solutions, such as GFRC, would have required additional supports, significantly increasing costs.
Strength
The sunshades are fixed on only two sides of the window frame, but light and sufficiently strong to resist high winds and earthquakes.
Durability
The airfoil-shaped design provides weather resistance.
Maintenance
The FRP sunshades require low maintenance compared to metal alternatives.
LCA/Environmental Impact
Using traditional materials would have required additional support, regulation, installation equipment, and maintenance. This composite solution provided a more sustainable approach while passing fire safety standards.