In this study, comparison of thermal insulation efficiency of some select materials frequently used as ceiling in building design was investigated. The results show that the five samples A,B,C,D, and E analysed in terms thermal properties can be thermally characterized into two major groups: sample A and C with higher thermal absorptivities and samples B,D and E with lower thermal absorptivities. Based on the molecular point of view of thermal absorptivities, samples B,D and E are recommended as the best materials with high thermal insulation inefficiency. Thermal mathematical medellings have also been developed for the two groups of materials which are substances with lower thermal absortivities and substances with higher thermal absorptivities. Graphs and tables have also been used to show the similarities and the differences for the different samples investigated.