hvac, balancing temperature, correct height to measure from floor....
 

in an approximately 7600 cubic foot basement area I have installed 4 - 4 & 12 inch ceiling supplies and 1- 14 & 20 inch return at floor level , where should i measure from floor up to get accceptable temp. reading,i.e thermostat says 70.....temp at 6 ft. up reads 70.....on couch it reads 65, is this common and or acceptable by industry standards ?

Sounds like the supplies have a poor throw. And are not getting the air close to the floor.