After that you can click finish to execute the cut.
Slice roof revit.
Load the family into the project and place it.
Highlight the main roof on the building model and click to select it.
Click by face or vertical.
Select a vertex edge face or point anywhere on the structural floor to start the split line.
Click modify tab geometry panel cut drop down cut geometry.
The pick roof wall edges tool is active so that you can pick the boundaries that compose the dormer opening.
Hope this is of assistance.
Create a sloped roof in revit step 1 draw your roof step 2 define the slope.
Create a void extrusion and make to required cut in the new construction phase apply the cut and done.
If anyone is still looking for a solution you can make a roof cut into an existing roof using component model in place.
Valid boundaries are highlighted.
Place the cursor in the drawing area.
Click modify floors tabshape editing paneladd split line.
Select the floor to modify.
Whether you want a double gable roof with 6 pyramid shaped dormers or a simple gambrel roof the basics remain the same.
Open the revit family with unattached voids and click create tab properties panel family category and parameters.
Start points and endpoints can be added anywhere on the face of.
In the family category and parameters dialog select cut with voids when loaded and click ok.
Revit roof slope can seem complicated at first glance but by learning a few critical features you can create any roof shape you desire.
See hd version of video tutorial here.
You can use the add split line tool to add linear edges and to split the existing face of a roof or structural floor into smaller sub regions.
This should keep you existing roof in tact and show a cut in the new construction phase.
Determine the length of the void ideally in 3d view at wireframe mode extend this in order to intersect the roof surface that will be cut use the cut geometry command and select first the roof than the void.
