Slate Roof covering $22,560 or $14.10 per ft. 2 Estimate includes setting up a new natural slate roofing system, and also underlayment, all blinking, on a cattle ranch design 1,600 sq.ft. Note, that slate is the heaviest roofing product that requires architectural reinforcement. On lots of homes it is not feasible to set up a brand-new slate roofing system in all. Eliminating old timber roof shingles or trembles will certainly set you back $1.20-- $1.50 per foot.