Where Revit is Different to other CAD Programmes

This section is intended to assist the migration from other CAD packages such as AutoCAD, ArchiCAD, 3D Studio or TriForma. If you have not used any of these programmes I would recommend still reading this section, as it will give you further insight into using Revit.

No Marks for Accuracy

It is not important how accurate you are initially with the placement of objects. All properties of every object can be changed at any time.

Peeling back the Layers

In most CAD programmes there is some form of layering system.
Layers are a drawing concept where collections of solids and lines are placed in abstract envelopes. It is up to the user to track (and understand) these layers and how they relate to each other.
Revit has a sophisticated; object based view system that removes the necessity (and danger) of layers. Revit also introduces the fourth dimension into the modeling process with the concept of Phases. Phases are intended to represent changes in the model over time and facilitate efficient group work. Near the end of this tutorial we will begin to use Phases in redeveloping the Villa Savoye.

You do not need to know your X,Y and Z's

Rather than to a static grid system objects in Revit are arranged in relation to other objects. Reference planes, structural grids and boundary lines exist to aid in establishing distances between objects.

Smart objects can be dumb

Revit's Object Based system can be limiting when compared to the simplicity of solid and line based modeling. When creating complex shapes a bit of thought must be entered into as to what the "blob" really is. At the time of writing Revit did not support the creation of very complex shapes such as spirals. The object model of Revit provides for the support of such objects in future releases.