In one embodiment, the present invention relates to a membrane for use as an outdoor building material comprising a non-reinforced TPO outdoor building material membrane composed of a single ply embossed thermoplastic polyolefin polymer wherein the embossed membrane has a stretchability in the range of about 5 lbf to about 30 lbf, as tested with about a 30-mil thickness sample under the “stretchability test.” In yet another embodiment, the present invention relates to a method of applying a non-reinforced TPO outdoor building material membrane to a motor home roof comprising the step of: a) applying a non-reinforced TPO membrane to RV roof wood deck, wherein the membrane is composed of a thermoplastic polyolefin polymer with at least one of the following ingredients of a fire retardant, a UV and thermal stabilizers, a titanium dioxide and a calcium carbonate and wherein the membrane has a stretchability in the range of about 5 lbf to about 30 lbf, as tested with about a 30-mil thickness sample under the “stretchability test” and wherein the roofing membrane has a whiteness of at least an L* value of 90 as measured by the Whiteness Test; and b) adhering the non-reinforced TPO membrane to the wood deck via factory or field applied adhesive with a minimum 4 PLI of peel strength under the ASTM D413 peel test.