In a wonderful neighborhood of classic bungalows, I have witnessed a travesty worse than removing the original wavy glass windows. The pitch must go something like this: “With this new metal roof, you will not have to worry about replacing it for many years” or at least that is the claim. There are many kinds of metal roofing and most importantly the method of attachment is critical to ensuring a water proof roof. Sadly, when you screw a thousand screws in the trough of the roofing panel you are doomed to have a leak, soon. Why, because the only thing between your attic and the rain water is that little black rubber washer they used to seal the screw hole. Take a look at the other type metal roofs (some with patterns stamped into them) that were used on original Arts & Crafts homes, there are NO Visible Screws on top of the roofing material! None, these installed were trained craftsmen.
A properly crimped metal roofing will last for a 100 years or more ( see the Basilica of St. Lawrence in Asheville), but not a 1/8 inch thick rubber washer held down, under pressure from over-tightened screw and super heated by the hot summer sun, then frozen by the shrinking metal roof at 15 degrees above zero, year after year! I have a worthless roof like I am mentioning on a commercial building and in year 6 some washers had gone missing and the imperceptible, at first, leaks began to ruin the insulation and finally the sheet-rock in the ceiling. Even though my installer only adhered the roof panels by placing the screws in the ridges between each trough/valley, they leaked.
If you really want to add class and character to your original bungalow, then have them install a fish-scale composite shingle. The original roofs with this type shingle have lasted 80 years or more. Call me and I will send you to see some. Chicken houses, barns, commercial buildings and sheds are supposed to have metal roofing, not $375,000 Craftsman Bungalows. Call your Preservation Society or Architectural Review Committee when you see this happening in your Asheville neighborhood. If you really want to have a metal roof, then look at these examples and add one that is not full of screws under pressure with little squealing rubber washers splitting open in the heat and cold. Love your Bungalows as they are a style to be treasured and there are people moving here that will pay extra, not to have vinyl windows and shiny silver metal roofs on their ideal bungalow. Please contact me with any questions or for the names of qualified, true craftsmen in the business of installing quality roofing materials. Asheville is fortunate to have several top quality roof contractors, you just have to know what to ask for in a metal roof. Best wishes.