All piping products expand and contract with changes in temperature. Linear expansion and contraction of any pipe on the longitudinal axis relates to the coefficient of thermal expansion for the specific material used in the manufacturing of the product. Variation in pipe length due to thermal expansion or contraction depends on the coefficient of thermal expansion and the variation in temperature (AT). It should be noted that change in pipe diameter or wall thickness with piping material properties remaining constant does effect a change in rates of thermal expansion or contraction. Approximate coefficients of thermal expansion for different pipe materials are are presented below. Expansion and contraction of PVC piping in response to change in temperature will vary slightly with changes in PVC compounds. However, these coefficients can be considered reasonably accurate.