Recessing the ceiling

[cwedge11]

We bought a mobile home a few months ago and have all kinds of ideas to remodel it. One thing we thought about doing is adding recessed square shapes in the living room. It is a 1983 Majestic Housing "villa" style 52 x 28. Roof is piched at about a 30 degree angle. We would like to drop the ceiling down about 6 inches and do an inset recess of about a by 7 ft by 5 ft. With adding 2 by 4s and sheetrock we are wondering if it would add too much weight. How could we find out??