Is there a satisfactory method of laying a protective shield over a 38 -foot-diameter sprayed urethane roof which was installed eight years ago. The roof is slightly pitched. While large blisters resulted during the first two years as the inch-thick urethane expanded, we used ceiling washers and thin nails to anchor them. About every two years I have had to apply aluminum paint to the surface to protect the roof against damage from the sun. I have considered cementing and nailing down a rolled-roof covering in triangular segments. Is there a better way? Justin W. Hicks Chebeague Island, Maine
The application of roll roofing glued or cemented to the urethane sounds plausible but don't use the nails. Lap ther roofing paper appropriately and make the joints water-tight.
You might also consider a regular built-up-type roofing overlay.
I suggest you discuss the problem and its solution with the original roofer. After all, the roof is only eight years old. Have him inspect the roof, observe its condition, and see what he would do about it.
If that roofer in unavailable, get in touch with a local reputable roofing contractor for the same on-site observation and recommendation.