FSA, LLC is a leading architectural firm based in Saint Louis dedicated to high-performance building solutions. The team specializes in creating energy-efficient designs that prioritize occupant comfort and long-term durability. By integrating Passive House principles, they ensure that every project minimizes its environmental footprint while maximizing thermal performance. Their approach combines modern aesthetics with advanced building science to deliver sustainable residential and commercial spaces. They focus on utilizing renewable energy sources and low-carbon materials to meet the challenges of a changing climate. Clients in the Missouri region benefit from their expertise in solar readiness and superior air sealing techniques. Through meticulous planning and innovative engineering, the firm transforms complex environmental goals into functional reality.