1、 Existing international research on building carbon emission

The UK government adopts the government's standard assessment procedure for energy rating of dewellings (SAP) to calculate the energy consumption and carbon emission of residential buildings.

The calculation results of building energy efficiency are represented by four values:

Energy performance per unit floor area, energy cost rating (SAP), environmental impact rating based on CO2 emission (EI), and carbon emission rate (DER).

ASHRAE in the United States has a carbon emissions calculation tool (ASHRAE special project: carbon emissions calculation tool) to calculate, express and compare building energy consumption, indoor air quality, sound, light and other factors, so as to calculate the total carbon emissions of buildings.

The German Sustainable Building Council (dgnb) launched the dgnb sustainable building assessment technology system in 2008, which takes the annual carbon emission per unit building area as the calculation unit, puts forward a complete and clear calculation method of building carbon emission, establishes a database of carbon emission of building materials and building equipment, and divides the whole life cycle of buildings into building materials production and building construction, building use Building maintenance and renewal, building demolition and reuse.

Summarizing the research results of building carbon emission abroad in recent years, it can be found that many achievements have been made in building life cycle assessment. For example, the international standard for the construction industry (iso21930), the German sustainable building certification body (dgnb), the Korean green environment evaluation standard (GBC) and the Japanese comprehensive environmental performance evaluation system of buildings (CASBEE). These evaluation index systems include the life cycle evaluation results starting from building materials. At the same time, various national research institutions have also developed building life cycle assessment tools, such as Canada's (Athena), Britain's (envest2), Sweden's (Eco-effect) and so on, showing the importance of the international community to building life cycle assessment.

2、 Principles and significance of the construction of carbon emission assessment system for urban buildings in China

Building carbon emission assessment system is to assess the impact of activities in the whole life cycle of buildings on the environment from the perspective of carbon emission quantification, formulate the standard carbon emission calculation framework system, and put forward the carbon emission indicators in each stage of the whole life cycle of buildings as the benchmark for evaluating low-carbon buildings.

"Energy efficient buildings" refer to buildings that meet or exceed the requirements of building energy efficiency design standards, and the building energy consumption index is used as the evaluation benchmark;

"Green building" refers to the building that protects the environment, reduces pollution, saves resources (water, energy, land and materials) and coexists harmoniously with nature in the whole life cycle of the building;

"Low carbon building" refers to the building that evaluates the impact of all activities on the environment in the whole life cycle of the building from the perspective of carbon emission quantification, reaches or exceeds the buildings specified in the low-carbon evaluation standards, and takes the carbon emission indicators in each stage of the whole life cycle of the building as the evaluation benchmark.

Compared with the green building evaluation system and the energy-saving building evaluation system, the building carbon emission evaluation system evaluates the impact of all activities on the environment in the whole life cycle of the building from the perspective of carbon emission quantification. Building carbon emission assessment system can put forward a unified carbon emission index definition value from the aspects of different national conditions, different climate characteristics and different building types, so as to evaluate low-carbon buildings globally and promote the exchange, promotion and application of relevant low-carbon emission reduction technologies.

3、 Evaluation system of existing low-carbon settlements in China

In December 2009, the real estate chamber of Commerce of all China Federation of industry and Commerce issued the green and low-carbon community assessment system. The system evaluates the building energy conservation, water conservation, greening and transportation of residential or community from the perspective of carbon emission quantification. On the other hand, the system puts forward the concept of carbon emission index benchmark value to measure the CO2 emission reduction in each stage of the whole life cycle of residential community. The system establishes a carbon reduction assessment index system of green low-carbon communities with Chinese characteristics according to the actual needs, and is based on meeting the basic requirements of the indicators in the technical assessment manual of China's ecological settlements. At the same time, each quantitative index of the system has relative independence to adapt to the change of benchmark; The selection and determination of indicators can be adjusted and changed according to different regions.

The full cycle carbon emission calculation is expressed in the form of chart below (for reference only, the specification shall prevail)

(1) Preparation and transportation of building materials

(2) Construction stage

(3) Operation and maintenance stage

(4) Demolition stage

4、 Significance and background

The launch of the general code for building energy conservation and renewable energy utilization is to implement the national laws and regulations on energy conservation, ecological environment protection and climate change, implement the decision-making and deployment of carbon peaking and carbon neutralization, improve the utilization efficiency of energy resources, promote the utilization of renewable energy, reduce building carbon emissions, create a good indoor environment and meet the needs of high-quality economic and social development. The scope of application is "design, construction, acceptance and operation management of building energy conservation and renewable energy building application system of new, expanded and reconstructed buildings and existing building energy conservation and reconstruction projects", involving new buildings, existing buildings, renewable energy system, construction commissioning acceptance and operation management. Xichuang system is committed to the R & D, production and sales of fabricated refined steel system curtain wall materials, which perfectly caters to the current development concept of large permeability, large span and slimmer curtain wall industry. Supply refined steel, fine steel, high-precision steel and precision steel curtain wall works.

The following are the normative provisions involved above:

General code for energy efficiency and renewable energy utilization in buildings (GB 55015-2021) (implemented from April 1, 2022, the full text is mandatory)

Standard for calculation of carbon emission from buildings (GB / T 51366-2019)

Evaluation standard for green buildings (GB / T 50378-2019)

Evaluation standard for green transformation of existing buildings (GB / T 51141-2015)

Strong system is committed to the R & D, production and sales of fabricated refined steel system curtain wall materials, perfectly catering to the development concept of large permeability, large span and slimmer in the current curtain wall industry, and providing a one-stop solution for building curtain wall! The company now has more than 40 patents related to refined right angle steel profile production equipment, production process and product appearance! Xichuang system takes "everything is for the safety of human life and property" as the mission and pursuit of the enterprise to further improve the human living environment.