ThermalWall is software that determines thermal properties of flat walls made of multiple homogeneous layers. It analyses the impact of temperature and heat flow variations on the interior and exterior of the wall.

Thermal transmittance is the measure of the amount of heat that passes through the wall. Internal areal heat capacity refers to the amount of heat that accumulates on the inner surface per unit area and unit change in temperature. Periodic thermal transmittance modulus is the measure of the thermal transmittance across a periodic wave. The ratio of inner to outer surface temperature represents the amplitude of the temperature wave at the inner surface over the amplitude of the temperature wave at the outer surface, when the heat passing through the inner surface is constant.
The decrement factor is the ratio of the periodic thermal transmittance modulus to thermal transmittance. The time shift of periodic thermal transmittance is the amount of delay or anticipation in the heat flow wave on the inner surface with respect to the temperature wave on the outer surface, when the temperature of the inner surface is constant. Lastly, the time shift between maximum temperature outside and inside influences the difference in timing of the temperature wave on the inner surface and the temperature wave on the outer surface when the heat passing through the inner surface is constant.
The calculations and procedures processed by ThermalWall are in accordance with the guidelines outlined in the European Standard EN ISO 13786 December 2007 "Thermal performance of building components - Dynamic thermal characteristics - Calculation methods (ISO 13786:2007)". Thus, the use of ThermalWall for measuring the thermal properties of walls is a reliable and efficient method.
Version 3.0.0.0: Relevant improvements have been made in the calculated quantities and the graphical interface.