The Research On The Public Building Envelope Energy-saving Design

How much energy a national has reserved to is an important factor to measure the development of the national economy. And it also restricts the development of the national economy. Since opening-up of the reform, the building’s daily energy consumption is growing faster than the rate of energy production. In the use of the building process, if we can make energy-saving measures, it will significantly reduce the consumption of primary energy and promote the sustainability of human development. Do a good job in building energy conservation is important.It can not only save energy, but also promote economic development, and promote the improvement of the atmospheric environment and indoor thermal environment. It’s also of great significance.This article describes the building energy efficiency design of several non-steady-state heat transfer analysis, building energy simulation software and energy consumption calculation method, building energy efficiency design principles.It focuses on the building envelope, including three structures:exterior walls, roof, outside the window.The energy-saving technical measures of the three are conducted in-depth research,. Thro ugh researching the thermal calculation method of thermal bridges, and the relationship between the exterior wall structure practice and the exterior of the average heat transfer coefficient, the article has summed up the windows than walls and the exterior heat transferthe coefficient of relationship. The same time, based on an actual project, uesing DEST energy simulation software to simulate the building under different conditions, improve the existing external walls and roof programs and analyze different facades, roofing, windows program advantages and disadvantages by comparative analysis method.Through deeply analysis and thermal calculation method,this article derives the relationship between the average wall heat transfer coefficient Km and△k which is the poor between the thermal bridges average heat transfer coefficient and the heat transfer coefficient of the external walls.It also obtains the conclusions that exterior structure practice superiors to the internal thermal insulation structure practice.So it recommends that specification wall heat transfer coefficient should associate with the window and wall ratio to ensure that the different parts of the heat transfer coefficient settings to meet higher energy efficiency standards. Through the analog, it summs up the relationship between the building of the window wall ratio and the building air conditioning energy consumption as well as the building envelope proportion of the overall energy consumption of the building order.