Fast Plans 11.1 is a graphic editor for quantity surveyors and architects that designs plans at both professional and amateur levels. You can redesign a building with certain ease, and you only have to insert wall measurements, the location of corners and use the included objects library to add doors, windows, more rooms, etc. You can also add all electrical installations.
It also comes with the SunTrack option integrated to orient the building so that it gains maximum natural light.