I had a portable shed with a torn cover after a few years. Repaired it with tarps silver side out for a while. After all was said and done the weathered tarps started failing. I drove my mini truck to the home center for tin roofing and some barn siding. Structured the front and back with 2x4's and siding then put siding lengthways down the sides ( 4' high ) and then roofed it/ overlapped with the siding. Ribs run the wrong way, but it works. Keeps the lawn equipment dry at least