Why applying building performance simulation? Building simulation is to assist the design teams to enhance their design. This work is meant to:

• identify opportunities for design improvements,
• compare different building designs and HVAC systems,
• prevent design pitfalls with regard to building envelope, insulation, daylight,  comfort, energy and others.

When performing whole building energy simulation? Whole building energy simulation can (for instance) be performed when a building is being certified under the LEED rating system or needs to comply with certain design standards such as ANSI ASHRAE Standard 90.1.

The design team should demonstrate a minimum percentage improvement in the proposed (design) building performance compared to a baseline building performance for benchmark purposes.

Why using simulations to validate building performance? Sometimes existing buildings and their installations need post-operational fine-tuning in order to achieve optimal performance. Some buildings use  temporary energy meters or advanced building management systems (BMS) including sub-meters which can collect energy consumption data. Simulation environment helps to demonstrate how to operate the building in order to achieve the optimum performance using measured data as an input to simulation. This can be useful when major alterations are undertaken.