Editing Shape Properties
Objects in floor plans need to have accurate sizes. To specify an object's size, use the fields in the Position & Size group in the Design tab. For more options, click the Dialog Launcher arrow in the bottom right corner of the group.
Here, you can specify the object's exact width and height in feet or other units depending on your scale setting.
Note: Use the object's "real" measurements. The drawing will automatically scale the object proportionately to other objects on the page.
You can also specify how an object should grow by clicking on the Shape Properties Dialog Launcher under the Design tab. Most floor plan shapes should grow Proportionally.
While you're still in the Shape Properties dialog, you can also specify whether you want to add automatic dimensions to the sides of your shape using Show Dimensions or display the calculated area of your shape using Show Area.