Commercial building owners hear a lot about energy efficiency, but the interventions vary enormously in cost-effectiveness. LED lighting and smart controls typically offer the fastest payback. Envelope improvements (insulation, windows, air sealing) depend heavily on the building type and climate. HVAC upgrades require careful analysis of existing system condition and remaining useful life. Delta Building Systems evaluates energy efficiency as part of every renovation and new construction project, helping owners prioritize the measures that deliver the strongest return given their specific facility.