The influence of wall's insulation thickness to building energy consumption

Wall insulation is one of the commonly used energy-saving measures. But many factors, such as climate, building type and indoor heat gain, have great influence on the effectiveness of building insulation. In this paper, the influence of thickness of building insulation layer on the building HVAC energy consumption has been analyzed for three different indoor heat gain, 20, 50, 80 W/m
²
, for an office building in Changsha, China. And results showed that the increase of thickness of wall insulation layer will help to reduce building HVAC energy consumption. But the increasing trend of energy saving rate would be reduced as the increasing of the thickness of building insulation layer. And for the building with higher indoor heat gain, the energy-saving rate associated with wall insulation tends to be lower.