The line between sustainability and resilience is a perplexing boundary. To many people, sustainability and resilience are interchangeable terms for a building that performs well; but to architects charged with designing for specific performance requirements, they may be very different. To understand this variability, it is useful to consider where the two sets of rules come in conflict, in order to evaluate which direction is right for a particular project. A few examples are outlined below.
Durability: Sustainability requires a building envelope to meet normal environmental challenges. Resilience demands higher performance enclosures to shelter occupants in an emergency.
Sun v. Wind: Sustainability uses deep overhangs to shade against heat gain. Resilience curtails overhangs for aerodynamic reasons, because wind uplift can rip off the roof.
Right Size: Sustainability limits the footprint to the necessary size for a given function. Resilience recommends building extra capacity for emergency use.
Renewables: Sustainability needs renewable energy generation on-site. Resilience requires products to be impact-resistant, and there are no solar arrays that have been tested… yet.
Redundancy: Sustainability streamlines a building’s dependence on utilities. Resilience requires redundant backups for power, water, and wastewater in case the primary source fails, thus doubling the infrastructure.
Materials: Sustainability uses low-embodied energy materials: rapidly renewable, lightweight, reclaimed, often wood materials for construction. Resilience requires high-embodied energy materials, such as concrete and steel, to protect occupants.
Windows: Sustainability prizes views, daylighting, and natural ventilation in an effort to reduce energy use. Resilience often limits glazing to small, fixed windows to meet very high performance requirements (and corresponding high costs) for extreme impact-resistance.
Perimeter: Sustainability indicates a narrow clear area between the building and existing landscape to preserve trees for shade and habitat. Resilience elects to have a wide perimeter to avoid collateral damage from falling trees, and reduce susceptibility to wildfires.