Rule 1: Never Explode CAD Drawing into the Families: In Revit it is suggested never to explode any AutoCAD file. Even when they are deleted every XREF will be treated like an imported symbol which will only add data to the file and also reduce the performance of the project. If you wish to explode any file make sure you purge XREFs first and also make sure you use the “purge unused” in Revit in order to avoid extraneous files. Try to utilise CASEs like “import from File” tool in order to import it to the separate Revit file and also make sure you remove ?rogue?rogue? style of lines with the help of program’s tool known as “change and replace linestyle” in order to purge the families and then you can finally load this into the active project.
Rule 2: Eliminating the Unused Families: It sounds more like any mafia act. Revit families that are no more the part of the model may still be contributing to the size of the file. To order to increase the performance purge use the families often as it makes it easier to remember which one shall go with the defined situation. Also make sure you remove only the families without touching the types as it may be hard to introduce them again once they had been erased.
Rule 3: Try Avoiding Extreme 3D Model Detail: In case of Revit family if it becomes too detailed there can be an impact on the model display performance especially in terms of large projects. In case highly defined models are needed try creating low and high detail version of required families. Try using the family type parameters while you switch between such versions based on the type of output required. The low detail version is expected to be quite simple (only a bounding box which depicts size and shape) with the visibility parameter staying turned off, whereas, the high detail version are allowed to be switched off temporarily for the purpose of exporting and visualization.
Rule 4. Use Families in Place of Group: To a fact families are considered to be lighter than groups. Thus, it is suggested to use families in place of groups as much as possible. Another reason of considering families over group is that even though groups are much powerful than families but it takes time to update all groups at instance which affects the efficiency of the project and design.
Rule 5. Avoid Over-usage of Voids: Voids can be considered to be of great use when they are utilised sparingly but they may impose penalties in terms of performance if they are used improperly or are overused. Many a time voids present the only way to model the elements accurately. However, it is suggested if possible try building the elements using solids instead of voids.
Rule 6. Avoid Formula and Array: The extensive usage of Formula and Arrays can add to the overall size of the families and thus it may affect their performance at the project level. Also if arrays are used sparingly in one family and the family is copied numerous times in the project the performance will still be impacted.