I have a 18 by 28 deck with a 24' dormer extending 8' over the deck from the house. The dormer is setting on two beams with a 4*4 supporting each end of the 24' trusses. the 4 by 4 are wrapped with the trex sleeves. I under stand the axial compression is 1200 lbs per sq in. Will the 4 by 4 support the weight. Snow load?