In which phase is seasonal testing performed?

• A. Planning Phase
• B. Design Phase
• C. Testing Phase
• D. Occupancy and Operations Phase

Answer: (D)

Seasonal testing evaluates how the building systems perform under real operating conditions across different seasons. Because this relies on actual occupancy, weather, and typical usage patterns, it happens once the building is in use during its Operability period. In this phase you can verify that HVAC, ventilation, controls, and related systems maintain comfort, air quality, and energy targets during winter heating and summer cooling, and that the design intent holds up under seasonal variations. The earlier phases focus on planning, design criteria, and construction and testing activities, which don’t capture the building’s performance with real occupancy and seasonal weather.