gallonsquare feet. Other websites say a gallon will cover 400-450 square feet of smooth surface. If you've got a rough textured surface or surfaces which need 2 coats of paint, a gallon will cover about 200 square feet. The above answer may be a general rule of thumb.
Highly rated roofing contractors tell us that asphalt is the most affordable roofing option, followed by wood, tile, metal, and slate. Materials for a metal roof can cost up to $350 to $1,500 per 100 square feet. Angie's List members recently reported paying an average of $12,236 for a metal roof installation.
For mid-grade, coated metal roofing, one might expect to pay up to $4.00 per square foot, with copper tipping the scales at over $6.50 per square foot. Of course, prices fluctuate according to the market price of the various metals used, as well as their availability for metal roofing manufacturing.n the lower end of the scale, a home owner can expect to spend anywhere from $1.20 to $1.50 per square foot for a decent metal roof, which of course does not include removal and disposal of old roofing material, but covers the average cost of material and installation.