Past studies on thermal conductivity of concrete use these three types of methods which include the two linear parallel probe (TLPP), plane heat source (PHS), and hot guarded plate (HGP) (Asadi et al. 2018). The HGP is a type of steady-state method in measuring the thermal conductivity of concrete (Zhang et al. 2015). The test method requires the test samples to be fixed between hot and cold plates so a constant heat stream can flow over the test samples. TLPP uses one probe that will be the heat source and the other probe will be the temperature sensor (Kim et al. 2003). Specifically for this research, the Transient Plane Source (TPS) method will be used where thermal conductivity is measured by sandwiching a singular spiraling flat sensor and probe between two concrete samples. The electric current passes through the probe to increase the heat and the sensor will measure the thermal conductivity (Asadi et al. 2018). But factors that are not mentioned in the ACI 122R – Guide to Thermal Properties of Concrete and Masonry systems, such as the probing depth and measurement time, may affect the value of the thermal conductivity of the sample since it affects the thermal diffusivity value. There are not enough past studies to determine how big their influence towards the result, hence further research is needed regarding the optimization of input parameters of thermal conductivity testing concrete to get the most accurate results possible.