Specify Building Parameters

The General tab displays project information that affects a heating and cooling loads analysis. You can modify this information before a loads analysis or after to make it comply with your specifications. The information on this tab can also be specified as Project Information, Energy Data. See Specifying Energy Analysis (gbXML) Settings.

Verify the building parameters that you specified when preparing the model, and make changes as needed.

  1. Click Analyze tabReports and Schedules tab Heating and Cooling Loads.

    If asked to turn on the Compute volumes setting, click Yes.

  2. In the Heating and Cooling Loads dialog, click the General tab.
  3. Adjust energy analysis parameters for the project as necessary.
    • Building Type - specifies the type of building according to the gbXML schema 0.37 (similar to ASHRAE).
    • Location - specifies the geographic location and weather for the project. Click , and in the Manage Place and Locations dialog, specify the location and weather. See Specifying the Project Location.

      You can specify location by selecting a city or by entering longitude and latitude values. The location establishes the climate and temperatures used in loads calculation.

    • Ground Plane - specifies the level that serves as the ground level reference for the building. Surfaces below this level are considered to be underground. The default level is zero.
    • Project Phase - specifies the stage of construction (Existing, New Construction).
    • Sliver Space Tolerance - specifies the tolerance for areas that will be considered sliver spaces. See Accounting for the Volume of Cavities, Shafts, and Chases.
    • Building Service - specifies the type of heating and cooling system for the building.
    • Building Construction - specifies the type of constructions. Click to open the Building Construction Dialog, where you can specify the materials and insulation (U-values) for the building.
    • Building Infiltration Class - specifies an estimate of outdoor air that enters the building through leaks in the building envelope.

      Infiltration can be specified as:

      • Loose - 0.076 cfm/sqft for tightly constructed walls.
      • Medium - 0.038 cfm/sqft for tightly constructed walls.
      • Tight - 0.019 cfm/sqft for tightly constructed walls
      • None - infiltration is excluded from the calculation of loads.
    • Report Type - Specifies the level of information provided in the heating and cooling loads report. You can specify Simple, Standard, or Detailed for Report Type.
    • Use Load Credits - allows for accounting of heating or cooling “credit” loads that take the form of negative loads. For example, heat that leaves a zone through a partition into another zone can be a negative load/credit.
    Note: You can also click Manage tabProject Settings panel Project Information to access the building type and construction parameters.
Parent topic: Using the Heating and Cooling Loads Tool