Your top 5 Revit questions answered!

When it comes to the detailed working processes within Revit, there is no clearly defined strategy within the software. Working practices may vary depending on the BIM requirements for the project, and in many cases there is no right or wrong way. BSBG’s Revit expert Alistair Bradley takes a moment to answer some typical questions from users, that help to define his working method.

1. Should I use a floor or a hatch region to define a material?

If you only want to see it on one drawing, then use a hatch region (for example a type of paint finish on a finishes plan). If you want to see it on multiple drawings then use a floor (for example a tile floor finish or a painted walkway within a car park). Provided that the types are clearly labelled in relation to their use, any confusion in schedules is eliminated. This does increase the risk that a user could put a level annotation on the car park walkway floor, which would be incorrect. Provided the risk is clearly defined and understood, then a more efficient drawing process can be achieved.

2. Should I include 3D modelled elements in 1:10 construction details?

As a general rule, the answer is ‘No’. Details are 2D with a 3D underlay for checking. The only exception is with Structural information. Where possible the Structural model should always be turned on, so any changes, or inconsistencies in the structural information can clearly be picked up at every scale of drawing.

3. I need a bespoke revision code sequence within Revit. How can I achieve this? (P1, P2, P3, then T1, T2, T3 etc.)

Within Revit you have a choice of numeric or alphabetical revision codes. You can create a bespoke code, however you are limited to one digit. Where multi-digit bespoke revision codes are required use the ‘issued to’ or ‘issued by’ parameter for the revision sequence! As an alternative, document control Revit plugins can override the Revit revision. This process will need to be clearly described in the BEP for the job to avoid any confusion.

4. How many Revit files should I use to set up a residential project with multiple apartment buildings?

To start with you need a separate ‘Site’ file. Within this file you will link your building files. This may be the same building repeated, or a different file for each building type.

To determine your approach with apartment layouts you need to answer the following question. Do apartment types repeat across different building types to a low, medium or high level?

If the answer is high or medium, then it will be efficient to use a Revit file for each apartment type. This is far more stable than trying to manage them through ‘Groups’. It will also help your file size and coordination.

If the answer to the question is low, there is no point in creating a Revit file for each apartment type as they rarely repeat across different buildings. Create Revit files for each floor type within an apartment building.  For example 1x ground floor 1x typical floor 1x top floor. If apartment types are repeated between the ground floor and typical floors then some manual coordination will need to be done. This can be done through the use of Groups.

Generally speaking, the apartment files will contain all internal information for the apartment. The Building file will contain the elevations / facade and balconies. Depending on the size of the project it may be worth having an additional Revit file for each staircase type. This would only be relevant if the same staircase was repeated across multiple buildings.

Finally, use worksets within the apartment and building files to manage the information that you load into the site file.  The site file can very quickly become un-manageable if every modelled item is loaded in.

5. I have a parking family that’s repeated within a parking array family and then inserted within the project. I want to control the dimension of the parking space (sub family) within the Revit project which means the individual parking space family cannot be ‘shared’.  Sub-families that are not ‘shared’ cannot schedule within the project.  How can I get the sub-family to schedule?

The simple answer is you can’t. You either control the parameters of the sub-family within the project or allow it to schedule. To overcome this problem you need to put the parking sub-family into a group within the parking array family. Then create a new parking family with an invisible line in it, ensure the new family is shared then place it into the same group. Your parking spaces will then schedule correctly, while also being adaptive to different project / authority requirements.

One problem still remains in the fact that sub-families cannot be associated with levels on a project, so you cannot schedule the total number of parking spaces on level 2 of a multi-storey car park (if you use parking arrays). Dear Autodesk, please fix this! I do believe that the production and process benefit of using parking arrays outweighs this constraint currently, however I see it as a software glitch.