Creating a Trey or Coffered Ceiling Using the Platform Hole Tool

Reference Number: KB-00738
Last Modified: March 22, 2017

The information in this article applies to:

Chief Architect Premier or Chief Architect Interiors


How can I use the Platform Hole tool to create a trey or coffered ceiling

Trey and coffered ceilings created using the platform hole tool


There are several ways to create a trey or coffered ceiling in Chief Architect.  Using the Platform Hole tool is among the quickest and easiest.

To begin, launch Chief Architect and either choose to Open a plan you want to create a trey or coffered ceiling in, or create a new plan by selecting File> New Plan from the menu.

In this example, we use a single 15' x 20' room with a ceiling height of 97 1/8".

If there is living space located above the trey ceiling in your plan, you may need to specify a lower Finished Ceiling height for the room so there is sufficient room in the floor/ceiling platform for the trey ceiling.

To create a ceiling hole

  1. Select Build> Floor> Hole in Ceiling Platform  from the menu.

  2. Click and drag a platform hole polyline in the room where you want to create a trey ceiling.


  3. To use the Move Object Using Dimension inline text feature to precisely position the edges of the platform hole, click on an edge of the polyline, then click on one of the temporary dimensions that display, enter in the exact distance value you want, and press Enter on your keyboard. 

    In this example, the ceiling hole is 24" from the walls of the room.

  4. Next, use edit tools such as Break Line , Fillet Two Lines , Chamfer Two Lines , or Change Line/Arc  to shape the platform hole as needed. Beginning in X8, You can use the Break Line Sticky Mode to make several breaks in your line without selecting the Break Line tool each time.

    In this example, we used Chamfer Two Lines  to chamfer the four corners using a Chamfer Distance of 24".

To create the sides of the trey ceiling

You can create sides of the trey ceiling using a Molding Polyline.

  1. Click on the platform hole to select it, then click the Copy/Paste  edit button.

  2. Click in an empty area of floor plan view to place a copy of the platform hole polyline at that location.


    You may receive a warning that "A floor or ceiling platform hole polyline is placed where the platform height changes, or where no platform exists. Move the hole so it's completely contained within a single platform." If so, click OK. 

  3. Next, use the Select Objects  tool to click on the copy of the platform hole polyline to select it, then then click the Convert to Plain Polyline  edit button.

    This changes the polyline from a platform hole to a plain CAD polyline with no special function.

  4. With the polyline still selected, now click the Convert Polyline  edit tool.

  5. In the Convert Polyline dialog box, select Molding Polyline and click OK.

  6. In the Molding Polyline Specification dialog: 

    • On the General panel, specify the Height of the molding.

      In this example, the height of the bottom of the molding is 97 1/8" which, as you recall, is the height of our room in which this molding will be placed.  

    • On the Moldings panel, click the Add New button and browse the Select Library Object dialog to select a molding profile. 

      Also on the Moldings panel, specify the Height and Width of the molding, the Offset, and be sure that the box beside Extrude Inside Polyline is checked so that the molding profile faces the inside of the polyline.

      • The molding profile used in this example can be found by navigating to Chief Architect Core Catalogs> Architectural> Molding> Crown Molding.

    • Click OK to close the dialog box and apply your specifications to the molding polyline. 

  7. Click on the molding polyline to select it and use the Move  edit handle which displays at its center to move the polyline into the same location as the platform hole inside the room.

    The platform hole and molding polyline are at the same location.  

To create the upper ceiling

  1. Select Build> Roof> Ceiling Plane  from the menu. 

    Creating a ceiling plane is similar to manually creating a roof plane: Click and drag to create the ceiling plane baseline, then release the mouse button.

    Click once to establish the location of the ceiling plane ridge.

    The ceiling plane displays with dashed pink lines and was drawn larger than the platform hole.  

  2. With the ceiling plane selected, click the Open Object  edit button to open the Ceiling Plane Specification dialog box and on the General panel:  

    • Set the pitch to 0 to create a flat ceiling.

    • Click the radio button beside Lock Pitch to lock it.

    • Raise the height of either the Bottom at Ridge or Inside Bottom.

      In this example, the upper ceiling is 12 inches above the lower ceiling, so its height is specified at 109 1/8".

  3. On the Structure panel of the same Ceiling Plane Specification dialog, uncheck Use Room Ceiling Finish and hit OK to confirm the changes. 

  4. Use the ceiling plane's edit handles to reshape the ceiling so that it is the same shape as the platform hole.

    Use the Break Line  edit tool as needed to add edges to the ceiling plane.

  5. Select 3D> Create Perspective View> Full Camera  and click and drag out a view in the room to see your trey ceiling in 3D.


What is the difference between a coffered ceiling and a trey or tray ceiling

trey ceiling (sometimes referred to as a tray ceiling) is a raised area in the middle of a room that takes advantage of the attic space above the room. It can be as simple as a vault that follows the roofline to a flat raised area or something more elegant that takes advantage of moldings to decorate the edges of the raised area.

A coffered ceiling is more like the ray traced picture below. The coffered ceiling divides the raised area with beams and moldings. Sometimes this area is part of a trey, and sometimes it is simply the support mechanism for the floor above.