Concrete Per cubic yard? Framing Per square foot of floor area Going rate: $30 / SF Roofing Per square (a square is 100 square feet of surface area, which means the slope of the roof is a factor). Asphalt Shingles: $425 / Square Drywall Per square foot of floor area, with a modification for complexity and for level of finish (Level 3 is default). Going rate: $10 / SF Electric Rough wiring: Per square foot of floor area Service Install: …