I am making the third addition to a slab foundation parapet roof single story house. The original house was built 1946 and I am trying to use Home Designer Pro 10 to create a framing plan:
ceiling joists are 96 ½” above finished floor and are 2x6’ 16 o.c. and run South to North.
The floor to bottom of parapet roof joists is 108”. The joists are 2x4 16” o.c. These also run North to South with a slope of ¼” per foot.
The exterior walls are slump block 12’ height
First room addition 15’x26’ 1992:
Walls are 2x6 16” o.c. 12’ tall to match existing roof line
Roof/ceiling 2x12 16” o.c. running East to West with a slope of ¼ per foot
Ceiling height 123.75” (east side) 120” (west side)
Second room addition 15’x15’ 2013:
Walls are 2x6 16” o.c. 12’ tall to match existing roof line
Roof/ceiling 2x12 16” o.c. running South to North with a slope of ½ per foot
Ceiling height 122 1/2” (South side) 115” (North side)
Third, in planning stage multi room addition:
This final addition is a multi room addition which removes part of the original roof, raises it to match the 1992 addition, and removes a 1946 garage roof and incorporates this freestanding structure to be part of the main house. It’s roof/wall system to match the 1992 specs.
The problems I am having are trying to create roof framing plans where:
All roof planes are flat (¼ pitch minimum)
All exterior walls are 12’
different rooms have different ceiling/roof heights, different ceiling roof compositions, or use the roof as the ceiling (1992, 2013)
different rooms have different roof heights
different rooms have different joist directions
I have read tutorials on the methods to make a parapet roof structure, built a second story with short walls, no roof or ceiling, and use the 2nd story’s floor as the 1st stories roof. This technique works great if the roof is the same height for the whole building, but I cannot make it work with a varied roof height. So three big problems:
The wall framing is wrong; instead of one wall made up of 2x6x144” lumber I get 1st floor wall with a “pony wall on top.
The bigger problem is I cannot figure out how to “change the absolute 2nd story floor height (1st floor to bottom of 2nd story floor) room to room. The last problem is I cannot seem to get the joist direction tool or bearing line tool to work. I can apply them but the 2nd story floor joists do not change direction.
Any help welcome!