Level Dimensions are point-level elevation markers common to architecture and site planning. They measure the element’s vertical height along the Z-axis. They are available in the Floor Plan and in Worksheet/Detail windows. They are not available in the Section/Elevation/IE window or 3D Document. To place a level dimension in your Project, select the Level Dimension tool, then click anywhere in the window. The elevation of the active story is immediately displayed along with a standard level dimension marker.
The Level Dimension Marker style can be chosen from the pop-up in the Level Dimensions Info box: The units used by the Level Dimensions are a project-wide preference set in Options > Project Preferences > Dimensions. Click the Level Dimension icon and choose your preferred measurement unit. The origin from which Level Dimension values are calculated is set in Level Dimension Tool Settings. You can edit the level dimension text separately as well as drag, rotate, and otherwise modify the text independently of the marker.
The Level Dimension markers are individual elements, and each one can be individually edited. They can be dragged, rotated and mirrored, with or without copies, as any other element. If multiplied together with the reference element, the copies of the markers will be associated with the copies of the elements. If you multiply only the Level Dimension, the copies will be associative with the same element (or the story level) as the original. Level Dimensions placed with Gravity On on top of Slabs, Roofs, Shells or Meshes are associated to them.
Associated Level Dimensions remain linked to the elements they were placed on top of, even if they are no longer inside the contour of these elements. If a Level Dimension falls outside the contour of the element it is associated to, its value changes according to the following rules:
• With Slabs, there is no change: the value is the same as if the Level Dimension were still inside the Slab’s contour.
• With Roofs, the value displayed is calculated by a projected extension of the roof (that is, what the value would be).
• With Meshes, it is the Story’s height that will be displayed (but the Level Dimension remains associated to the Mesh).
When placing a new Wall, Column, Beam or Object-type element, the Gravity function lets you place it directly on top of an existing Slab, Roof, Shell or Mesh, thus taking on the elevation of the element it is placed on. If Gravity is on (activate Gravity icon), newly created elements will be placed on top of (i.e., gravitate to) the Roof, Shell, Slab or Mesh beneath them, depending on which Gravity option you choose. Level Dimensions placed with Gravity On on top of Slabs, Roofs, Shells or Meshes are associated to them. To choose an option, use the Gravity controls in the Standard toolbar or the icons of the Coordinates palette.
Note: Gravity only affects newly created elements and cannot be used for editing existing ones. If you are using Gravity to place a Wall, Column, Beam or any Object-type element onto a Slab, Roof, Shell or Mesh surface, you can monitor the changes in elevation (Z) values in the Tracker (or the Coordinates Palette). When several Slabs, Roofs, Shells or Meshes overlap, the highest elevation value is displayed. See Tracker. In this image, a Wall (with Gravity on) is being placed on top of a Slab whose elevation is 400; the Wall’s Z-coordinate in the Tracker, accordingly, is shown as 400. If the Gravity function is on (activate Gravity icon) while you are placing a new element, but there is no underlying Slab, Roof, Shell or Mesh, then the new element will be placed at the current story’s zero level.
How to Modify Dimension Texts of Several Level Dimensions
When you want to modify all or even some Level Dimensions in your project say in a way to make them refer to Reference Level 2 instead of Reference Level 1 (please see the Manual for more details on the Reference levels!), the obvious solution would be to select all text boxes then change them in one step. However, when you select all level dimensions, the dimensions themselves get selected and it is the Level Dimension Settings dialog that will open when double-clicking on the Tool's icon or pressing Ctrl+T (Cmd+T on the Mac).
In order to make the Dimension Text Settings dialog open, instead of the above mentioned one, you need to do one simple step prior to opening the Tool Settings dialog: having selected the Level Dimensions you would look to change, just add a single Dimension Text to the selection as well. In this case, the Dimension Text Settings dialog will open when pressing Ctrl+T (Cmd+T on the Mac) and all changes made in that window will apply to every selected Level Dimension. In the screenshot below you can see the Dimension Text Settings dialog open, when the selected Level Dimensions are set to refer to Reference Level 2.
To do this, simply click on the Insert Autotext checkbox, open the pull-down menu to the right of it, and select the option you want - in our case Reference Level 2.
NOTE: Reference Levels are display and input aids. Actual Elevation values are always calculated from Project Zero.
To learn more about Reference Levels, please read the relevant sections in the Manual.