So boolean operations are a no-no in Maya… Then how do I model an arched door for this church?
First, create a polygon tube and rotate and scale it to the size of the arch. Delete the bottom half faces.
Fill the hole that results from deleting the faces with the Append to polygon tool.
Extrude those faces down to the bottom of the building.
In the front view, move a few of the top vertices upwards to make an arch shape.
Using the Split polygon tool, make new edges highlighted below.
Move vertices so that they roughly fit the arch shape.
Delete unwanted edges so that the door part is one face.
Either leave the door face and texture it, or delete it to make a door like below.