SThermal insulation plays an important role in building energy savings. Previous researchers mainly
focused on the exterior building envelope insulation. However, interior building envelope insulation
can also reduce the building energy consumptions by minimizing the heat transfers between adjacent
zones at different temperatures, especially for the multi-zone buildings. In this research, we studied
the thermal insulation performance of the glass fiber board used for interior building envelope. Firstly,
a mathematical model was developed to predict the effective thermal conductivity of the glass fiber
boards. Then the mathematical model was validated by the measured thermal conductivities of four
sample glass fiber boards with different thicknesses. Finally, we used eQuest to simulate the heating
energy consumptions of a typical residential building using central heating system and the glass fiber
boards as the interior building envelope insulation. The simulations were conducted in two different
climatic zones in the northern China. The simulated results indicated that there was considerable heating
energy saving potential by using the glass fiber boards as the interior building envelope insulation.
Nevertheless, the glass fiber boards were not suggested to be too thick, for the energy saving percentages
increased slowly when the insulation thickness was above 20 mm