Insert a standard window into a wall that has already been modeled. Do this by clicking on the "Home" tab followed by the "Window" icon.
Click the "Load Family" icon to bring up the Imperial Library. Browse through the library and select a standard window type. This "Family" will be loaded into your project automatically once you properly insert it.
You can also load a family from an outside source, such as a downloaded family from a website. There are many free families available online (see Resources).
Click on the wall where the window will go. Revit will automatically place the window in the wall.
Select the window and click the "Edit Family" icon in the "Modify Windows" tab. This tab will automatically appear when you select the window in the wall. A new window will open when you choose to edit the family.
Click to "Save As" and save this family as a new name so you don't overwrite the existing window type.
Click the "Types" icon under the "Manage" tab to add new types and sizes of the window. This is a good idea if you want to use a similar window type, but for many different sizes. The specific window sizes will be saved under the same "Family" in order to keep the type organized.
Select the frame and click "Edit Extrusion" to modify the frame depth.
Select "Load Into Project" under the "Manage" tab to place this new window in your specific project. This will automatically load the family into your browser so you only need to do this once.
Press "Save" to save all the changes that you made to the family. This is important if you plan on using this window type in multiple projects.