This project belongs to civil engineering field. 70% of Shanghai's 560 million square meters of existing residential buildings lack energy-saving measures, resulting in low energy efficiency and poor indoor thermal comfort. However, there are the following technical problems in implementing energy-saving renovation: 1) The existing energy-saving renovation evaluation methods lack accurate grasp of the actual operating energy consumption of the building, one-sidedly emphasize the thickness of the insulation layer and ignore the insulation performance of the building, making the expected energy-saving renovation effect impossible to achieve; 2) The transformation method lacks pertinence, and the transformation process cannot simultaneously solve the contradiction between system safety, durable structure, convenient construction, less disturbance of residents and high cost performance. It is easy to cause social problems, and large-scale energy-saving transformation is difficult. Supported by the national "Eleventh Five-Year Plan" scientific and technological support project "Research on Key Technologies for Building Energy-Saving Renovation"(topic number: 2006 BAJ01A03), through a large number of field surveys and test analysis, this project systematically proposes for the first time a practical energy consumption model of buildings that are more suitable for Shanghai's climate characteristics and living habits and the corresponding energy-saving renovation evaluation method, fully ensuring the scientific nature of the energy-saving renovation plan. The energy-saving renovation technology system developed based on the characteristics of Shanghai City buildings has successfully solved the technical problems of building adaptability, construction difficulty, structural safety, technical economy and disturbance of residents existing in conventional renovation technology. All project research results have been incorporated into the Ministry of Construction's "Guidelines for Energy-saving Renovation of Existing Residential Buildings in Hot Summer and Cold Winter Areas"(2012), and have been promulgated and implemented to guide energy-saving renovation work in hot summer and cold winter areas in my country. The main innovations of the project include: 1) It took the lead in establishing an evaluation method for energy-saving renovation of residential buildings based on the actual energy consumption of buildings, successfully controlled the gap between theoretical analysis results and actual results to within 15%, and proposed the energy-saving renovation technical routes of "focusing on heat insulation in summer, supplemented by winter insulation" and "changing windows to main, appropriately integrated" effectively solved the problem that existing methods seriously deviate from reality and improved the scientific rationality of the renovation plan. The basic energy use database established during the research process covering information related to 267 residential buildings (more than 10000 households) provides effective data support for the establishment of building energy use models. The developed building dynamic insulation performance evaluation platform provides an objective basis for scientific understanding of the importance of heat insulation to building energy-saving renovations. 2) The plastic-steel coating technology developed for metal exterior windows effectively solves the problems of internal decoration damage, construction difficulty, material waste, serious disturbance of residents and economy caused by direct replacement of metal exterior windows. On the premise of retaining the window frame, the window sash and other parts are covered with plastic. According to the test results, the steel-plastic composite method can reduce the comprehensive heat transfer coefficient of the existing steel window from 6.18 W/m2℃ to 3.74 W/m2℃, which is convenient to construction and relatively low to transform. 3) The biggest feature of the energy-saving and decoration integrated exterior wall energy-saving renovation technology developed by the project is that it converts complex on-site manual operations into the factory, avoids quality risks during the construction process, and shortens the traditional 8-step construction steps to 2 steps, and the organic combination of insulation and decoration fully reflects the dual effects of the insulation system on the protection and decoration of the envelope structure, and solves the problem of damage to the insulation system and the reduction of energy-saving effect caused by mismatch of facing materials and improper construction. 4) The light steel structure roof system developed by the research team effectively solves the structural load constraints faced by the current flat slope conversion of existing building roofs. All parts of the system are factory-produced and quickly installed on site. The weight is only 10% of that of traditional concrete roofs. The developed simple planting roof system (planting soil thickness less than 100mm) and root-blocking waterproof material effectively solve the risk of leakage. During the implementation of the project, 13 relevant standards and specifications (3 national standards and 4 industrial standards), 13 patents (including 5 invention patents), 5 product production lines, 2 test platforms, 3 monographs, 18 published papers, more than 30 comprehensive energy-saving transformation projects (more than 500,000 m2), and direct economic benefits of 181.94 million yuan were compiled. The retrieval results show that the research achievements have reached the international advanced level.