Autodesk Revit: Drawing Aids explained


In Revit, Reference Planes can be used to form construction lines to help set out your design. However, it is usually quicker to just place the element into the project and adjust it retrospectively. In this Revit Tutorial, I’ll show you some of the features of Revit that facilitate that quick manipulation of elements- both at the time of creation and also once they are in the model.

Unit Agenda

  1. Temporary Dimensions
  2. Alignment Lines
  3. Object Snaps

Temporary Dimensions


If you used any CAD system before, you’ll be used to the concept of Dimensions. However, in Revit we have two distinct versions of a dimension. We have Permanent Dimensions and Temporary Dimensions. Permanent Dimensions are placed into view and used to communicate information (ie lengths, angles, etc) to someone else- ie the Contractor. Temporary Dimensions are a working tool to enable you to make very quick and easy changes to an element’s position. Temporary Dimensions are always displayed in blue. As you are placing a length of wall (as n the above example), you can see the temporary dimension being displayed. If you know the actual length that the wall needs to be you can go ahead and just type the value using your keyboard and hit “Enter”. Revit will then instantly make that section of wall to that length.


A more typical use of Temporary Dimensions is when editing the position of elements that have already been placed. Let’s take a look at the image above as an example. I have 3 wall elements placed in my model. Let’s say I need to adjust the position of the right hand wall. I go ahead and select it. At this point, it then appears as the image above- ie the selected element (the wall) appears in blue and temporary dimensions appear in order for me to make a quick edit. Let’s say the distance between the two short walls needs to be 7000mm (and not 7767.2mm). With the temporary dimension visible (7787.2), I can simply click on this value (to activate the input box) and type in my new value (7000). The right hand wall will immediately move to the left by the appropriate distance. Please Note: Temporary Dimensions depict the distance from an element to it’s surrounding neighbours. They do not depict the length of the element (that you have selected) itself.

Alignment Lines


When placing elements into your model, you will notice (as you move your cursor around) that light blue dashed lines appear in your view. These are called Alignment Lines- and are produced by Revit in order to help you align elements with each other. In the above image, I am currently placing a section of wall into the model (the wall at the bottom of the image). As my cursor gets (depicted where the purple cross is) gets close to being aligned with the end of the top wall, you can see how Revit suddenly draws a vertical line between the two. Revit is suggesting that I may wish to align the end of the lower wall with the end of the upper wall. You can almost think of these Alignment lines as temporary construction lines that Revit created on the fly as you place new elements into your model.

Object Snaps


Every CAD system known to man has a feature called “Snaps”. Snaps allow us to quickly find pertinent points on our elements- be it End points, Mid points, centres of circles, etc. Revit is no exception and contains a fully-features Snaps system. All snap points are automatically recognised as you hover over them with your cursor when picking points.



If you wish to override any (or all) of the Snap points that Revit identifies, you can easily do so by right-clicking anywhere in the active window. Doing so will bring up a context-sensitive floating menu. On the menu you will see an option for “Snap Overrides” (see above image). Hover over this and a sub-menu will appear. On this sub-menu you can choose a specific snap point that you would like Revit to target. On the “Manage” menu (Ribbon bar) you will find a detailed Snap menu where you can configure which snap points Revit looks for in it’s general operation.

Key Points

  1. Revit contains a variety of tools to enable you to make very quick changes to you elements
  2. Temporary Dimensions allow you to quickly change the distance between a selected object and it’s neighbours
  3. Alignment lines acts as temporary construction lines and are generated automatically
  4. Revit has a full site of Snaps. These can be overridden using the floating, context-sensitive menu.
This tutorial is taken from "The Complete Beginner's Guide to Revit Architecture" FREE online course.
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Posted in Autodesk Revit.