Understanding Line Weight Basics
One of the first concepts new Autodesk® Revit® users need to grasp is how to control visibility and appearance of objects. Most users start off as great modelers, but fall short with construction documentation because they are unable to get all the objects to look correct on paper. This article will look at all the major components that control the line weight appearance of objects.
Revit uses a numbering system to assign line weights to objects. Numbers range from 1-16 and may vary depending on the scale of the view. This table can be found by selecting Line Weights from the Additional Settings pull-down located on the Settings panel of the Manage ribbon.
Figure 1: Object line weight table
Once you get a grasp on how these line weights print you need to verify they are associated to your objects. This is done at a global level by accessing Object Styles found on the Settings panel of the Manage ribbon.
Figure 2: Object styles
Figure 2 shows objects with their associated line weights assigned for a projected display and a cut display. Even though these values can be overridden, these settings are global for your project. As shown in Figure 2, a column would use a line weight of 1 if the view range does not cut through the column. However, if the column is cut by the view range, then the line weight of 4 would be used. You can also assign a line color, line pattern, and material to your objects.
By now, hopefully you understand the link between your view scale and the line weight assigned to your objects. The next component that comes into play is the detail level of your view. Depending if your detail level is set to Coarse, Medium, or Fine, control of how your objects display will change. The lower left-hand corner of your view is where you assign the detail level. This is shown in Figure 3. The detail level can also be set in your Properties palette.
Figure 3: Detail level
Figure 4: Detail level with scale comparison
Figure 4 shows the differences in combining different scales with detail levels. You will notice that a coarse detail level will display columns with a single line representation. When the scale is changed from 1/8”=1’-0” to ½”=1’-0” the column shows crisper in the coarse level of detail. Once the detail level changes to medium, the column is represented with double lines showing the web thickness. And finally, when the detail level is changed to fine you get a true representation of the column showing the fillet at the web.
Override Line Weight
Sometimes you may have a view created in your project where you want to use different line weights then previously set up in the global settings. This can be done using your visibility graphics. Every view in your Revit project can have different visibility graphic overrides applied.
Figure 5: Visibility Graphics override
When you select a category in your visibility graphics you have the option to apply an override to the line weight used on the object for the view you are editing. This is shown in Figure 5. This override will not change other views in your Revit project; it will affect only the visibility graphics of your current view.
There also may come a time where you need to control the line weight of just a few objects and not all the objects in a view. Maybe there is an existing column on a plan where you need to display it with a lighter line weight. This could be handled with phase filters; however, let’s assume this is a small job and you did not have the time or possibly the knowledge to apply filters to your project. Revit allows you to apply overrides to individual elements without affecting the same objects in the view or other objects in the project.
Select the objects to which you want to apply the override, and then select Override Graphics in View from the shortcut menu. Using the By Element option will change only the selected elements. Selecting By Category is the same as editing the category in the visibility graphics explained previously. The final selection is By Filter, which allows you to select elements to which to apply an override based on a defined filter.
Figure 6: Visibility Graphics override by element
Figure 7: By Element line weight overrides
Other Visibility Basics
When you are working at a small scale with the detail level set to Coarse, objects may appear very bold when you are zoomed in on them. You can toggle your line weights on and off using the thin line display tool.
Figure 8: Thin line display tool
Another major obstacle for Revit beginners is view range. Sometimes you will draw a beam in a plan view and you just do not see it, but when you switch to 3D view it is there.
Figure 9: View range
Every plan view has a property called view range. The view range is a set of horizontal planes that control object visibility in the view. The horizontal planes are top, cut plane, and bottom. The top and bottom clip planes represent the top-most and bottom-most portion of the view range being displayed. The cut plane is a plane that determines at what height certain elements in the view are shown cut. As mentioned previously, the cut display has its own line weight assignment versus projected. These three planes define the primary range of the view.
View depth is an additional plane outside of the primary range. You can set the level of view depth to show elements below the bottom clip plane.
You may have the need to show some structural framing such as a mezzanine level in your view. When you adjust your view range to display a mezzanine level, the framing in the main plan disappears. Revit’s Plan Region tool allows you to define an area of your plan that will have its own view range different than the properties of the view. Think of it as a view range override.
Figure 10: Plan Region
Figure 11: Plan Region view range override
Hopefully, some of these basics will help you ramp up your skill set inside Autodesk® Revit® Structure.