Optimization Analysis Of Insulation Layer Thickness Of Office Buildings In Cold And Severe Cold Regions

Building wall insulation is one of the most effective ways of saving building energy.The type and thickness of insulation materials will affect the energy saving effect of the wall.The increase of wall insulation thickness will reduce the building energy consumption,but will lead to an increase in the initial investment of insulation materials.Thus,there is an optimal insulation layer thickness,which would induce the lowest total cost of insulation materials(the sum of building energy consumption cost and initial investment cost)during the whole lifetime.Based on building energy consumption calculated and life cycle cost theory,the optimal thicknesses of different building insulation layers is determined.An office building model is established,which thermal insulation layer thickness meets energy conservation standards.The established model is used to study energy consumption,energy saving rate and life cycle cost of different thermal insulation material and different thermal insulation layer thickness.Finally,the optimal insulation materials and their thickness of the established office buildings model were determined according to the net present value method.Stuty indicates thatenergy saving effect of the office buildings in severe cold region,which adopt the optimal insulation layer thickness is far greater than that in cold area.Office building wall insulation layer thickness increases will reduce the heating load in winter,but lead to cooling load increase in summer.Study also shows that increase of the insulation layer thickness under building ground floor is not conducive to increase building energy efficiency.In cold and severe cold regions,EPS is the most economical insulation material if the life cycle is 30 years while vacuum insulation panel is the most economical item if the life cycle is 50 years.There is a apparent gap between the optimal insulation thickness determined by the the life cycle cost calculation and that by the present energy saving standard.In order to achieve the optimal longterm benefits,it is suggested to optimize the insulation thickness in the actual project according to the life cycle cost optimization.The results of this paper can be used as a reference for office building insulation schemesde termining in cold and severe cold regions,and building energy saving design and renovation.