This work took up a study on the performance of TBC-using Silica Fume (SF) and Metakaolin (MK) as pozzolanic materials - under elevated temperatures ranging from 200 °C to 800° C with intervals of 200° C for one hour. Various tests such as compressive strength test, split tensile test, acid attack test and rapid chloride permeability test were done for TBC mixes and compared with the behaviour of unheated mixes. Taking 10% SF replacement as constant, while varying the proportion of MK as 5%, 10%, 15% and 20%, mechanical and durability properties were studied. Test results showed that the mix with 10% SF and 15% MK had better mechanical and durability properties under elevated temperatures than other mixes.