I have worked for about 6 hours trying to learn how to use dormers and cannot get it. I watched videos on dormers and how to construct a one and a half story structure. I have a 30' x 40' garage that has a living space above it but is not a true 2 story. The first floor is 120" high. The second story walls are 26" high on the (40') side with a gable roof on the 30' wall. The pitch of the roof is 10:12 and from the floor to the pitch of the roof on the inside is about 177" from the 3/4" finished floor. When I try to put in an auto dormer it says that my ceiling is too low. When I put in a floating dormer it says dormer roof does not meet base roof, etc. I have completed dormers before to make it look presentable, but they were not done correctly. The dormers I am making are 216" wide and the walls are supposed to be 96". I have Chief Architect Premier X13. Please help.
Thanks!