Automatically Generated Roof Styles

When roofs are automatically generated, a roof plane is created over each exterior wall by default, resulting in a hip roof.

To generate a roof plane using values other than the defaults or to not generate a roof plane at all (gable roofs, shed roofs, etc.), change the settings in the Wall Specification dialog before a roof is generated.

Select a wall and click the Open Object

edit button to open the Wall Specification dialog. The Roof tab controls how the roof plane above the selected wall is automatically generated.

Auto Rebuild Roofs

When Auto Rebuild Roofs is checked in the Build Roofs dialog, any changes made to the position of an exterior wall or to its roof directives will automatically prompt the roof to regenerate to reflect the changes. See "Build Roof Dialog".

Changes made to floor heights, ceiling heights, or floor or ceiling platform thicknesses may also cause the roof to be automatically rebuilt.

Wall Specification Dialog

Many common roof styles can be generated automatically using the Roof tab of the Wall Specification dialog.

Note: Pitch settings on the Roof tab of the Wall Specification dialog override the Pitch setting in the Build Roof dialog.

Any automatically generated roof style other than a hip requires one of the Options to be checked.

Full Gable Wall - Check this to create a gable above the entire wall. This places a ridge over the middle of the selected wall(s). See "Gable Roof".

High Shed/Gable Wall - Check this for the wall under the high side of a shed roof. It can produce ridges, but it may also be used for gable ends that have a raked wall. See "High Shed/Gable Wall".

Knee Wall - Check this to define an interior wall whose height is defined by the roof plane above it, not the ceiling height. Knee walls are usually found next to top floor attic areas.

Extend Slope Downward - Check this to extend the roof plane downward over a bumpout, instead of creating additional roof planes. The two connecting walls that create the bumpout must be Full Gable walls.

In the bottom image below, the outer bumpout wall has the Extend Slope Downward check box selected. The two short connecting walls have the Full Gable Wall check box selected.

Roof Cuts Wall at Bottom - Check this to have the bottom of the selected wall clipped by the roof plane below, as where a floating dormer wall meets the main roof plane.

Pitch

If the Pitch value is followed by a [D], the value is the default pitch for the entire building. The default pitch is set in the Build Roof dialog. The minimum pitch is ¼" in 12" or 20 mm in 1000 mm.

Pitch - Specify the pitch for the roof plane above this wall if different from the default roof pitch set in the Build Roof dialog. If a roof plane is specified with two pitches, this field controls the pitch of the lower roof plane.

Upper Pitch - Check this to define the pitch for a second roof plane above this wall. Mansard, gambrel, gull wing and half-hip are examples of roof styles that use two pitches.

Starts at - Specify either the height or the distance in from baseline where the second roof plane begins.

To determine either of these values from an elevation view

Create the model.

Generate the roof using only the first pitch. Be sure to define all the roof information for each wall (gable, hip, first pitch, etc.).

Using the Cross Section/Elevation

tool, generate a cross section of the house that includes the roof plane that will have the second pitch.

Using the CAD tools, place a temporary point near the location where you want the second pitch to start.

Using the End-to-End Dimension

tool, drag a dimension line from the first floor 0'-0" to the temporary point.

Using the End-to-End Dimension

tool, drag a dimension line from the baseline to the vertical plane of the temporary point.

Enter either of these values in the Wall Specification dialog. You can press the Tab key to update the other value. Click OK to close the dialog.

Open the Build Roof dialog, check Build Roof Planes and click OK to rebuild the roof.


Note: Normally hip roof planes are built over bay, bow, and box windows. You cannot edit the wall segments making up these windows as described above. Instead, select one of the windows, open it for specification, and select one of the roof generation options.

Overhang - Specify the overhang of the roof plane to be generated above the selected wall. The default value is set in the Build Roof dialog. See "Build Roof Dialog".

Lower Wall Type If Split By Butting Roof - Designate a wall to be split into a pony wall. It is split by roof planes that abut its outside surface. The upper portion retains the same type. This is defined on the Wall Types tab of the Wall Specification dialog, and the lower portion specified here. See "Wall Types Tab".

Auto Roof Returns

Check Auto Roof Return to generate roof returns on the selected wall. In most cases, roof returns only work for Full Gable Walls.

Specify a Gable, Hip, or Full roof return and whether the roof return is Sloping or Flat. See "Roof Returns".

Check the boxes to Include Frieze molding and Include Gutter along eave edges.