Can you guarantee that the completed building will match the performance predicted by the analysis in its day-to-day operations?

• Why or why not?

No, it is not guaranteed that the completed building matches the performance predicted. While the analysis does give a good estimated prediction, there can be differences in the day to day operations due to changes in products used such as light bulbs or sensors in the actual construction. Moreover, if energy efficient practices are not practiced by building occupants, factors such as plug loads or lighting efficiency can deviate from predictions. Additionally, since the analysis can take into a account a range of values, the average may not actually reflect the actual performance of the completed operating building.

When choosing settings for each of the building performance factors, should you always choose the setting that gives the absolute lowest predicted energy use?

No, it is not practical to choose the lowest predicted energy use. The predicted performance would not be an accurate and realistic prediction for the actual finished building, since that would imply high cost that may not be in budget or unattainable goals. Instead, it is of best practice to be realistic while still working to reach the target performance goal. This can be done by balancing performance factors. If you want to follow the modeled design exactly for WWR, for example, you can compensate a high factor in that element by using a better performance value for glass material or window shades. It becomes a balancing act of keeping realistic predictions while working to reach target performance.

How can model-based quantity takeoff improve the design process?

How can designers improve their designs using the information provided by preliminary estimates of the cost of building their design ideas?

Model-based quantity takeoff provides preliminary cost estimates that can significantly improve the design process by providing realistic predictions of unit and total costs for the main elements of the design structure. Using these predictions reflected in the summary report, the involved parties of the design process can make informed decisions on materials to use, square footage, and dimensions of the design to adhere to the budget targeted. Since these are available readily during design, if any changes have to be made, they can be done prior to further development of the project and construction, therefore saving time and money.