Message: Cannot Produce a Roof Plane

Reference Number: KB-02911
Last Modified: July 20, 2022

The information in this article applies to:

Chief Architect Premier or Chief Architect InteriorsHome Designer Professional or Home Designer Architectural or Home Designer Suite


When I use the Build Roof dialog to create an automatic roof, this message displays: 

"Cannot produce a roof plane."

What is causing this problem?


When a roof is generated automatically in Chief Architect, the program will try to build a roof plane bearing on top of each exterior wall in the plan, excluding Full Gable and High Shed/Gable walls. The program will also join each roof plane with adjacent roof planes, forming geometrically correct valleys, ridges and hips. When conditions in the plan prevent the program from doing this in any part of the plan, it will present this warning message.

There are a wide variety of reasons why this warning message might display.

The most common reason is that floor and ceiling heights in some part of the plan are such that the program cannot create roof planes over that area and have them join properly to the roof planes in the rest of the plan.  This condition may also be accompanied by walls that have been incorrectly set as Full Gable, High Shed/Gable, Knee Walls, or Extend Slope Downward.

To use the Reset to Defaults dialog

  1. Click File> Save As  from the menu to save your work in a new plan, giving the file a unique name.

    This allows you to return to your first plan in its original state if resetting the values in the Reset to Default dialogs does not make the type of changes that you had expected.

  2. Select Build> Roof> Delete Roof Planes  from the menu to remove existing roof planes from the plan. 

  3. Next, select Edit> Reset to Defaults from the menu.

  4. In the Reset to Defaults dialog:
  • Click the radio button for Reset Scope to All Floors.

  • Check the boxes beside Floor HeightsCeiling Heights and Roof Directives in Walls.

  • Click OK to close the dialog and restore these defaults throughout the plan.

  • Rebuild the roof (if Auto Rebuild Roofs isn't already enabled), then go through setting each wall directive and adjusting the Floor/Ceiling Heights again, one at a time.  Double check the 3D camera view of the roof as you make changes to gain a better understanding of their effects on the plan.

  • If you continue to have issues with your roof: