A change in temperature is known to affect the deformation properties of a clay specimen. In order to study the effect quantitative y and its dependence on clay type a number of oedometer tests were carried out. Conventional incremental oedometer tests as well as constant-rate-of-strain tests were used. Test results clearly show that the preconsolidation pressure decreases with increasing temperature; the compression modulus is little affected. Five different clays were tested, and the change in preconsolidation pressure was found to be larger for higher clay content of the specimen. The research shows that laboratory testing at different temperatures gives the necessary information for the calculation of temperature induced settlements.