Thermal mass in buildings refers to the capacity of construction materials to store and release heat, governed by the relationship

Q = m × cp ×ΔT 

where

Q is the heat exchanged
m is the material mass, and
cp its specific heat capacity
ΔT is the temperature difference of inside and outside

Materials with high density and specific heat capacity, such as (concrete), adobe, brick, or stone, can absorb substantial amounts of thermal energy even at minimal temperature variation. This stored energy can subsequently be released during cooler periods, thereby moderating fluctuations in indoor temperature. The effectiveness of thermal mass is further influenced by the material’s exposed surface area and ventilation, which determine the rate of heat discharge to the surrounding environment.