How tall are you?
With the screen at 28", the bottom of the projector will be around 71" from the floor. 36" = 79" Since the lens on the sony has a max length of
11.4 for that size screen it will be right above your head. You could move it forward since the fan noise is not too bad and it exausts to the front.
Other things to consider. Do you have a ceiling fan, w/light kit or ceiling light fixture? Both of these things need to be considered bc they may get in the way. Personally, I would get the projector as high as possible and let the screen fall where it may. Additionally, front speaker arangement, center channel, equipment, furnature could all be placed underneath screen.
Hope this helps.