the several parameters must be adjusted such that when the sheet is rolled the outward facing layer is stretched to a degree which is greater than the degree to which the other layer is compressed that is when the sheet or surface covering is unrolled the elongated layer must overcome the compressed layer such that the surface covering is initially stretched to a dimension greater than its original unrolled dimension the respective layers may be so designed that the sheet may be rolled with the decorative layer facing outward or inward in the roll depending on the elongation and compression characteristics of said layers after the thermoplastic sheet surface covering has been formed in accordance with this invention it is stripped from the strippable carrier and rolled so that stresses are built into the sheet by the above described stretching and compressing forces acting on the layers while the sheet is in rolled form as is the usual custom the sheet is shipped to the installation site where it is unrolled cut to size and installed when the sheet is installed and before the stresses therein are relieved by securing the sheet along the periphery thereof and over the surface to be covered the stresses set up in the sheet create a built in self induced tension such that the.