I usually just set it on the existing window sill!
But, I did see one under a window in an apartment complex -- made it handier for maintenance.
Remember, people normally stand | sit near | on the floor. In fact, I only see someone hanging from the ceiling at the circus --
also, conditioning the area near the floor saves ENERGY.
I usually install window shakers with a slight tilt to the outside. re: level.
height of unit is usually called elevation AFF [above finished floor]
[Edited by cem-bsee on 04-17-2006 at 07:42 AM]
harvest rainwater,make SHADE,R75/50/30= roof/wall/floor, use HVAC mastic,caulk all wall seams!