Not having enough of these protective substances can cause stones. Changes in the Acidity of the Urine. Changes in the acid balance of the urine can affect stone formation. 1  Uric acid and cystine stones mainly form in acidic urine.
1 For an average sized 1,500 square foot roof, that works out to a total PVC roofing cost of $6,000 to $18,000. 2  While certain types of PVC roofing material can be installed over the existing roof, the old roof may need to be removed and disposed of at an additional cost of $1.00 to $2.00 per square foot. While certain types of PVC roofing material can be installed over the existing roof, the old roof may need to be removed and disposed of at an additional cost of $1.00 to $2.00 per square foot.
1 Do-it-yourself materials to install an asphalt shingle roof on an average one-story ranch-style home (with a gently sloping roof of 1,700-2,100 square feet) can run $680-$3,700, depending on the quality of the materials. Roofing with synthetic slate tiles (recycled rubber or plastic molded to look like slate) is about $11,900-$18,900 for an average ranch house with a 1,700-2,100 square foot roof; or $21,000-$27,000 for a 3,000-square-foot roof.