Journal of Northwestern Architectural University (Natural Science Edition) Inverted roofing and new type of insulation material Yang Xiaoping, Li Dong2, Wang Cuiping3(1. Institute of Architectural Design, Chang’an University, Xi'an 710061, China; 2. Department of Architecture, Chang’an University, Xi’an, Shaanxi, China 710061;3. School of Architecture, Xi'an University of Architecture and Technology, Xi'an, Shaanxi 710055, China) Analyzed the general insulation roof material. Problems that are prone to occur during construction and use, and difficulties that cannot be solved; The feasibility and advantages of inverted roofing are described from the perspective of materials and construction. The conventional practices and precautions of inverted roofing are introduced; and one of the new insulation materials is also introduced. Extrusion polystyrene insulation boards were introduced. Ordinary roofing; Inverted roofing; Insulation material; Extruded polystyrene sheet 1 Traditional practice Roofing is a very important part of the building envelope structure. The waterproofing and insulation of the roofing are directly or indirectly affected. Construction quality, energy conservation and other aspects. For a long time, roofing practices have used more traditional practices (). Which insulation and waterproofing is the focus of construction. The moisture content of the insulation material is a fundamental problem affecting the insulation effect. In the traditional roofing practice, commonly used insulation materials Yang Xiaoping (1965-), female, Sichuan Santai, a registered architect of Chang'an University, mainly engaged in architectural design theory materials such as cement expanded perlite, cement vermiculite, Mineral wool and rock wool are all non-hydrophobic. If such thermal insulation material absorbs moisture, its thermal conductivity increases sharply, and the thermal insulation effect will be greatly reduced. Therefore, ordinary thermal insulation roofs need to be waterproof layers on the thermal insulation layer. In regions where the latitude 40* is north and where the indoor air humidity is greater than 75%, or where the indoor air humidity is more than 80%, the steam insulation layer is also required under the insulation layer to isolate the penetration of indoor water vapor into the insulation layer. This will lead to complex structures and increase the cost. Cement inflated perlite, cement vermiculite and other thermal insulation materials are inorganic gelling materials. During the construction, on-site mixing is required. The water consumption is relatively large. The leveling layer is also a wet operation. It is necessary to ensure timely evaporation to achieve the moisture content under natural dry conditions. Not easy to do, this is also a factor affecting the insulation effect. Although organic cement insulation materials have been used in recent years, because of the fierce competition, the quality cannot be guaranteed, and the actual moisture content greatly exceeds its test report, and the heat insulation effect is difficult to meet the design requirements. The waterproof layer of ordinary insulation roof must protect the roof and protect the insulation layer. The waterproof material is exposed to the uppermost layer. Due to the temperature change and other factors, it is easy to age and shorten the service life of the waterproof layer; and the protection is added to the waterproof layer. Layers will add additional investment. Some projects use exhaust roofs due to difficulty in drying the insulation and screed. Because of the large number of exhaust holes protruding from the roof, it not only affects the overall sense of the roof, but also artificially destroys the integrity of the waterproof layer. The rain cover on the exhaust hole is often easy to knock off, but it is rain poured into the hole. Even if the exhaust passage is provided according to the specifications, there may be a bubbling phenomenon of the waterproof layer in the exhaust hole. In summary, the problem of traditional insulated roofing is mainly reflected in the complex structure and some unnecessary waste. The requirements for construction are high. Whether it is the waterproof layer on the insulation layer or the vapor barrier layer below, poor handling will cause the insulation material to absorb moisture and absorb water to increase its thermal conductivity, thereby reducing the insulation effect. Another important point is that the waterproof material is exposed to the uppermost layer, which is affected by thermal stress, ultraviolet rays, and other factors, and is rapidly aged and shortens its service life. 2 Inverted Roofing Feasibility Inverted roofing can avoid these problems. The so-called inverted roof, according to 94, roof engineering technical specifications. 6061 Aluminum Plate,Aluminum Plate,5052 Alumiminum Plates,5182 Aluminium Plate Zhengzhou Yearshine Industry Co., Ltd , https://www.zzyscorp.com