2.0.1 Model Preparation

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Model Preparation 

It is advisable to spend a little time checking that models have all the information required for analysis and for use in the application. This may involve how the model is created, Revit Settings and whether thermal properties have been assigned to elements. The application will also assist in checking for issues and advising on any modifications required.

All Model Types

      1. Check that the Site Location is correctly set in Revit since this will affect Solar Data. This may be set in the Manage Tab – Location.
      2. Model Orientation on site should be correctly positioned. You may need to rotate True North in Revit to achieve this. This may be done in the Manage Tab – Rotate True North. (Please do not rotate the model in a Revit View as this will not achieve the same outcome).

      1. Check that your Levels are correctly set and that they align correctly with building elements.
      2. Ensure that the Building Type is correctly set in the Energy Settings.  This will define the occupancy hours. Alternatively, this may be adjusted in the Building Manager.  
      3. Create an Energy Model in Revit and check for relevant warnings in the Manage Tab – Warnings.

          1. Check that the Phase in the Energy Settings matches the one set in the Revit View.
          2. Check the Perimeter Depth in the Energy Settings is correct (typically it is set to 20 feet or 6 meters).
          3. Use Masses for Surrounding Objects/Neighboring Buildings.  These can be included, if you wish, to calculate Shading Effects.
            Mass Models
            1. Assign Mass Floors in Revit by selecting the Mass and using the Mass Floor Tool on the Revit Menu.
            2. You may set Target Percentage Glazing in Revit’s Energy Settings or control this later in the application. 
            3. The Mass should physically touch the Level that is defined in the Energy Settings (the Ground Plane).
            4. The Mass should be created as recommended. This may be done by modeling level by level while in the Mass Editor.  When you click on ‘Finish’, this will be one mass but when surfaces are assigned in the application will be adjustable on each level.  Extruding a mass from a footprint to the roof level will limit your ability to control separate zones.
            5. Avoid core extrusions within the Mass (elevator/core shafts etc).
            Detailed Models
          1. Check that Thermal Properties are set for elements in Revit.  Analytical Properties (R-values and U-values) will need to be assigned to model elements.  This may be checked by selecting elements and using Edit Type to check if these are assigned.
          2. Avoid large gaps in the building enclosure.  Gaps in the building enclosure may produce mixed orientations and interfere with the results displayed.
          3. Check thatAreas and Volumes’ is used under ‘Rooms and Areas’ in Revit.
          4. Element Functions should be correctly set.  Exterior walls and Floors should have an ‘Exterior’ function.  Internal Walls (solid and curtain walls) should have an ‘Interior’ function.  Elements with Interior functions will be excluded in the results.
          5. Avoid overlapping elements (floors/walls etc) or multiple instances of elements in the same position.
          6. Ensure that relevant elements are Room Bounding.  Linked models should also be Room Bounding (this may be set in the Host model).
          7. Check that Rooms/Spaces are placed correctly and upper limits extend to the the next level.  This is relevant when using the Spatial Elements Option.
          8. Check Room Computation Heights are correct for measuring the room perimeter.
          9. Place Spaces over Ceilings if using Spatial Elements option.  This will ensure that all external wall areas will be included in the results.
          10. Avoid Room separation lines around the model perimeter.  These will also interfere with Energy Analysis as rooms and spaces should physically touching bounding elements.
          11. Curtain Walls should be centered in Host walls to read fully with the Spatial Elements option.  Curtain Walls that are placed with an offset may not be included in the results.
          12. Note that Stacked Walls in Revit may not read correctly with Spatial Elements.
          13. Avoid Double Layers of Walls with glazing hosted on the inner wall.

        The Model Diagnostic Tool may also be used to check the model before starting Energy Analysis.  This Tool will advise of issues in the model.

        For more details of each item, Please refer to Sections 12.1.1, 12.1.2 and 12.1.3 below.


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