MEP File Size Maintenance_Modelling

File size maintenance is extremely important in the MEP project environment. Due to the amount of consultant files (Revit and DWG) normally linked into a project, the amount of views (Both plan, ceiling, schedules, 3D, sections, elevations, sheets, etc.) being created, the project can become quite heavy and thus computer performance will start to suffer. There are quite a few remedial actions one can take to keep a MEP project file size as small as possible.

This entry will focus on a modelling method example. The basic principle of Revit, irrespective of being an Architectural, Mechanical, Electrical, Plumbing or Structural project, is not to over model. Too many complex geometrical shapes will decrease computer performance, as well as affect the overall project file size. 

We will be using the example of duct hangers as 3D objects and duct hangers as 2D objects in the Do-Nut-Stop project. A comparison will then be made between the file sizes.

Circular ducting will be placed on the curved line as indicated below.

One of the drawbacks to creating ducting on a curved route, it that one cannot natively draw ducting as a curve, nor can we draw ducting by picking lines. Thus the ducting will have to be drawn in sections. Using the curved line as a duct route placeholder, ducting can be drawn at sections of 1475mm using the curved line as a placement point. 

I have created a simple 3D hanger family which contains very simple geometry, with 7 parameter dimensions to drive the hanger diameter, offset from its level, etc. 

Krantz-type diffusers have been placed in the project as well 

The 3D hangers have been placed at equal intervals (One hanger supporting one duct segment). 

Even though the hangers looks extremely good in any view, when we look at the file size after only a few 3D hangers were placed, we will see that the file size is quite large: 10.5MB              

Should we rather decide to draw hangers as a 2D repeating detail, as per the image below, we will notice that the overall file size decreases with at least 2MB! You will have to make the decision: Do you really NEED to see hangers in 3D? What will it contribute to the overall file size? How will it affect your computer's performance, especially on large and complex project files? I will leave the decision up to you.