The shape editing tools were designed to allow for moderate slopes and in such cases variances in true thickness are trivial.
Revit roof shape editing.
The shape editing tools display on the contextual tab.
This also adjusts the position of the roof if the support and the roof are not aligned.
Revit structural project 08 roof 0pen web steel joist framing and modify grid duration.
On this flat slab you add one or more points and then adjust the z height of those points.
Use pick supports to split the roof element at the supporting beams.
This will modify the form of the roof and allow for customized roof shapes.
However more significant slopes will increase this variance.
Use shape editing to add internal drains to the roof built using sloped insulation.
Floors and roofs that have been shape edited will not report a true thickness.
In the example below we add a bunch of points and change their relative height with modify sub elements tool.
First select the roof.
A roof cannot attach to another roof and the roof cannot be a curtain roof.
Floors must be flat and on a horizontal plane.
Revit will issue a warning when a slope significantly deviates from the expected thickness.
An alternative way to apply slope to a roof or floor is the shape editing tools.
Modify the height of points to create the desired slope.
These are available on flat slabs only.
Add points manually or create them automatically with split lines.
You will see shape editing tools from in your ribbon contextual tab.
In order to enable shape editing tools the following conditions must be met.
By specifying the elevation of these points you split the surface into sub regions that can slope independently.
Shape editing tools are used to create flat roof slope.
This shape editing tools will not appear if you define the roof slope.