This is the roof for the Customizable Modular Building. Open the Customizer and set the number of windows for the front and the sides. Then save the STL file and print it.
This is sized for an N scale model railroad layout.
I used the following settings on my MakerBot Replicator2 to print this design in PLA. I didn't use a raft and support is not needed.
Infill = 10%
Layer Height = 0.200
Shells = 1
Feedrate = 40
Travel Feed = 55
Temperature = 220