Multi-year outdoor firewood storage requires a heavy-duty poly tarp with a minimum thickness of 12 to 16 mils (0.012 to 0.016 inches) and a minimum weight of 7 to 8 ounces per square yard. This structural thickness, fabricated from UV-stabilized High-Density Polyethylene (HDPE) with a 14x14 weave count, provides the necessary tensile strength and abrasion resistance to withstand sharp log edges, heavy snow loads, and prolonged ultraviolet degradation without tearing or cracking.Black & White Ext