outdoor shed growers i need some advice

ok i'm doing and a 5'x8' room (5'x5' flower) by puting up a wall in my existing16x8 building in a semi shaded yard roof is shingled and i'm gonna insulated ceiling and walls inside room,ive done an attic grow mid summer full sun on the room and eventually had to abandon exhaust fans for portable a/c because of power limits in building and distance from the house(running more power not and option now) i cannot run an a/c and the 1000 hps and 104w cfl's in intended veg cabinet the building is eleveted and air beneath seems to be cooler because of the 3 ft of space between it and the ground and the fact that it buts against wooded area ok to end my rambling my question is this a 1600 cfm gable fan with a 24" square plywood light trap to exhaust and one 24" passive intake light trap for intake pulling from beneath shed should staying close to outside ambient be possible??