Building energy efficiency is an important task of China's construction industry in this century, China's relatively poor in energy resources, however, China's energy consumption was ranked in the forefront of the world, energy consumption accounts for a large proportion of the construction site. Building energy-saving project for creating a conservation-minded and innovative society has a very important meaning.


And exterior wall thermal insulation system of classification.


External wall insulation system consists of: thermal insulation system of exterior wall and exterior insulation and finish systems. 1, exterior wall thermal insulation system: mainly internal insulation of external wall structure, the advantage of quick construction and operating flexibility, especially in construction of high-rise building has certain advantages. The downside is: take the usable floor area of the building, prone to thermal bridging, cracking, impact the second decoration, interior insulation structures vulnerable to damage. 2, exterior insulation and finish systems: is the outer wall external thermal insulation layer. It is composed of the adhesive layer, insulation, connectors, plastered reinforced protection layer and veneer layers. Outside wall insulation system has very obviously of superiority, insulation layer is located in buildings enclosure structure of outside side, reduced has due to outside temperature changes led to structure deformation and produced of stress and the stress accumulation, avoid has snow frozen, and hot and humid dry cycle caused of structure damage, reduced has outside harmful gas and material on structure of erosion, on subject structure up to has protection role, thus effective to improve has structure of durability. Used outside wall insulation system also can improve and improved wall body of waterproof and gas key sex, avoid has wall body internal condensation knot dew phenomenon of occurred, outside wall outside insulation and outside wall within insulation compared to, can increased buildings of area, in on both buildings energy transformation Shi, on households interference less, on buildings internal II times decoration Shi, on original of outside wall insulation system damage small. Exterior wall thermal insulation system of building thermal stability, warm in winter and cool in summer, more and more people of all ages.


Second, several kinds of external thermal insulation system.


1, polystyrene particles external wall thermal insulation system: is a use of expanded polystyrene granule insulating material, alkali-resistant fiber mesh, crack resistance of anti-crack mortar, PuTTY, flexible elastomeric polymer emulsion primer system material (polystyrene granule thermal insulation material for short) in the shape of new exterior wall heat preservation system. 2, pouring of polystyrene Board and the wall molding, this technology is mainly used in reinforced concrete frame-shear wall structures, polystyrene is built into buildings within a template, and pouring of concrete and polystyrene molding compound wall. 3, polyphenylene Board exterior wall thermal insulation system: is divided into expanded polystyrene and extruded polystyrene plates. 4 seamlessly, solvent-free polyurethane foam spray exterior wall thermal insulation systems: a technique that uses no cavity structure, has a strong ability to resist wind pressures and water resistant, its tectonic weathering resistance, insulation resistance, crack resistance, stability and shock resistance are superior.


Third, problems and prevention measures of external wall insulation systems.


1, security issues. Fire safety of the main exterior wall thermal insulation material, exterior wall thermal insulation material to fall off and the top veneer loss problems.


Fire safety: the main purpose is to prevent fire, flames igniting insulation materials from among jambs, preventive measures are: to strengthen fire prevention on the perimeter of the hole in the door and window insulation, to prevent the burning of exterior wall thermal insulation material.


Shedding problem: exterior wall thermal insulation material or decorating materials falling from a height, the consequences are very serious, especially high-rise buildings, the consequences are unimaginable. Therefore, practical measures must be taken to prevent dropping. External wall insulation system due to wind loads, we all know that building bigger high wind, exterior wall under wind loading is also bigger, tends to have a Canyon effect between the tall buildings, walls experience a great deal of negative pressure suction, plus weight of exterior wall thermal insulation material or decorating materials, it is easy to get sucked down. Control measures are as follows: at present, commonly used on special adhesive and anchors mechanically fastened (commonly used stainless steel bolts and plastic expansion anchors), in order to prevent loss.


2, thermal insulation wall crack of easy problems.


External wall insulation system insulating material, mortar, brick walls or concrete material properties, the difference resulting in material temperature of denaturation can, under the influence of outside temperature, materials have different temperature stress, temperature and strain ranges between layers of different temperature and strain and crack, causing water seepage, thermal insulation performance of exterior wall thermal insulation system is greatly reduced. Crack resistant mortar is usually used in engineering, the laying of alkali-resistant fiberglass mesh or heat galvanized welded wire mesh and other enhanced network's approach to resist cracking.


Exterior wall thermal insulation technology is the key to modern building energy conservation design, is the focus of building thermal insulation properties, is the common diseases treatment techniques commonly used in building construction. An in-depth analysis of application of external wall thermal insulation technology in construction engineering, can promote the development of energy-efficient buildings in China, promote the improvement of construction quality, disease management technology in China.