You have a floor object containing a split face region which cannot be selected or edited in a floor plan view.
Revit cannot split face slope floor.
By specifying the elevation of these points you split the surface into sub regions that can slope independently.
If we switch to a 3d view we can clearly see the triangulated sloped section of our floor.
You can use shape editing tools to manipulate the surface of a flat non sloped floor or roof by defining high and low points for drainage.
This could be say a walk in shower in the corner of a wet room.
Key points you can use shape editing tools to manipulate the surfaces of your floor elements.
Shape edit examples use shape editing tools to slope a constant thickness floor or the top surface of a floor with a variable thickness layer.
Click modify floors tabshape editing paneladd split line.
This video shows the process for the split face function for floors in revit architecture.
The view properties view range view depth must include the floor object in order for the split face to be selectable in a floor plan view.
But now revit will only triangulate the area inside the split line boundary.
Specify a value for the defines slope and slope properties for a single floor sketch line.
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.
Select the floor to modify.
Select a vertex edge face or point anywhere on the structural floor to start the split line.
This is often the result of a curved face.
Add a floor material use split face add another material.
You can create sloped floors in the building model.
Normal manipulation of model patterns move align and rotatable will only apply for straight planes so to fix this unwanted deformation we need to manipulate surface by height.
Specify a value for the offset from base property for parallel floor sketch lines.
Working with hardscapes or sloped floors it sometimes happens that a model pattern will deform or behave strange in revit.
Use one of the following methods.