Step-by-step guide

Create a new roof type and assign new roof types to existing roof elements.

Open the project RF_Arch_ Roof Types_RVT2021.rvt. It opens in the 3D view.
Zoom in on the garage and corridor, and in the Visual Control Bar, change the Visual Style to Shaded.

In the Revit interface, the 3D view zoomed to the garage and corridor, and in the View Control Bar, Visual Style expanded, with Shaded selected.

Select the main roof.
In the Type Selector, select Basic Roof: Wood Rafter 8ʺ – Asphalt Shingle – Insulated.

In the view, the main roof selected, and in the Type Selector, a new roof type selected.

The roof updates.

In the 3D view, the updated main roof, with the garage roof selected, and in the Properties palette, Edit Type selected.

In the Type Properties dialog, the Duplicate button highlighted in red, and in the Name popup, a name entered, with OK selected.

In the Edit Assembly dialog, Layer 2 highlighted, and the Insert button selected.

A new layer is added.

In the Material column, click By Category and click the Browse (…) button.

In the Layers group box, in the Material column, By Category highlighted, and the Browse (…) button selected.

In the Materials Browser, “maso” typed in the search field, and in the search results, Masonry-Tile selected and highlighted in red.

In the Graphics tab, in the Surface Pattern > Foreground section, click in the Pattern field.
In the Fill Patterns dialog, change the Pattern Type to Model and select Shake.
Click OK.

In the Fill Patterns dialog, the Pattern Type set to Model, and in the list of patterns, Shake selected.

In the Material Browser, all settings configured for this example and highlighted in red, with OK selected.

In the Edit Assembly dialog, change the Thickness for the Masonry – Tile layer to 6".
Change the Function of Layer 3 to Thermal/Air Layer [3].
Change the material of the Thermal/Air Layer to Insulation / Thermal Barriers – Rigid Insulation with a Thickness of 2".

In the Layers group box, all settings configured for this example and highlighted in red, with OK selected.

In 3D view, the updated garage roof.

Modeling a dormer roof