O&S Associates, Inc. specializes in design and restoration, particularly structural/civil engineering and MEP services including historic preservation and facility renewal. Our engineering specialties include parking, MEP, structural, restoration, exterior envelope services, energy audits, façade law compliance, cogeneration, and HVAC. O&S provides sustainable design on all our projects. We maintain LEED Accredited Professionals as an effort to show our commitment to “Green” design.