To produce my plans, I have used a combination of AutoCAD (to create the raw plans) and then Photoshop (to apply textures etc). The results can be seen below.
Ground Floor Plan - 1:100 when printed at A3
First Floor Plan - 1:100 when printed at A3
Second Floor Plan - 1:100 when printed at A3
I also created a set of steel frame layout plans for each floor too.
Ground Floor Steel Structure Plan - 1:100 when printed at A3
First Floor Steel Structure Plan - 1:100 when printed at A3
Second Floor Steel Structure Plan - 1:100 when printed at A3