2.0.1 Model Preparation

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Model Preparation 

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 FenestraPro’s Building Manager.
          3. Create an Energy Model in Revit and check for relevant warnings in the Manage Tab – Warnings. Note: if the project has open plan areas it may take longer for the Energy Model to generate. It is recommended to place internal walls in Detailed projects so that the model conditions are as realistic as possible.

          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).  Note: When using the Building Elements Mode in Energy Settings, you will not be able to set the Perimeter Depth.  In this case, change the mode to ‘Use Conceptual Masses and Building Elements’ in order to edit the value.  The minimum value accepted is 1.5 meters (4.9 feet) and the maximum is 8 meters (26.24 feet).  If values are input outside these ranges (larger or lower), the application will use a default value of  6 meters (19.68 feet).
          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 FenestraPro
            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 surfaces created in FenestraPro 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 (either solid or void) within the Mass (elevator/core shafts etc).  To model voids inside a Mass, the footprint may be separated into pieces as required (the Mass remains as one when complete.  Voids and  extrusions which overlap however should be avoided as these tend to interfere with the identification of analytical energy surfaces.

            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. This will interfere with orientations and 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.  Note: The Energy Model in Revit may identify this as an external element despite the Revit function setting. The Revit setting however will be used by FenestraPro and the element will be excluded.
              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 next level.  This is relevant when using the Spatial Option. Creating a Room Schedule is helpful for identifying redundant rooms, rooms outside the model etc.
              8.  Check Room Computation Heights are correct for measuring the room perimeter. This is the plane at which the room area is calculated. In some cases this value may be set above the floor level and may cause issues if walls are sloping etc.
              9. Place Spaces over Ceilings if using Spatial Elements option. This will ensure that all external wall areas will be included in the results.  Note: This only applies to Revit v2020 and older.
              10. Avoid Room separation lines around the model perimeter (inside the envelope) which interfere with Energy Analysis. The model elements (walls etc) should define the bounding conditions but if room separation lines are present, these terminate the internal spaces instead, leaving the envelope surfaces excluded from the Energy Model.
              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 may not read correctly with Spatial Elements. This is because properties cannot be assigned to these wall types in Revit.
              13. Avoid Double Layers of Walls with glazing hosted on the inner wall.

            1. Review warnings in Revit under the Manage Tab.  This will list any issues in the model which are affecting a successful Energy Model.  Not all issues may be listed here however.  For instance, Masses which have void extrusions or are modeled as one extrusion from Ground to Roof will not appear as issues but these conditions may affect analysis results.

          1. Check that internal walls do not extend into the core area of external walls (this may interfere with identification of elements and energy analysis)

              1. It is recommended to Close any Revit plan views if they are open in the background.  Also the application is best used with a default 3D View rather than using other Revit views.
              2. Structural Columns that are set to room-bounding may cause issues (high results) if they are touching or very close to glazed elements. A workaround for these is to temporarily set them to non room-bounding.
              3. Curtain Panels must be modeled as panel families in Revit (not wall families) to allow analysis. Wall families cannot be assigned Glass Types under Type Properties (Analytical Properties) or by using the Glass Database in FenestraPro.
              4. Avoid placing openings to create wall opes and then inserting glazed elements into these voids. This typically interferes with the Energy Model in Revit and the glazed elements may not be identified. These areas may not then receive analytical surfaces and be excluded.
              5. If Energy Surfaces are fragmented and appear to be missing some areas, you may adjust the analytical resolutions under Revit’s Energy Settings to get a more accurate surface. Under the Analyze tab on the Revit menu, find the Energy Settings and adjust the Analytical Resolutions. Note: the Energy Model may take longer to create depending on resolution settings and results in the application may vary as resolutions are adjusted in Revit.

              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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