Interpretation of the implementation of general code for water supply and drainage and water saving in buildings

Recently, the Ministry of housing and urban rural development issued the announcement of the national standard general code for water supply, drainage and water saving in buildings, approving the general code for water supply, drainage and water saving in buildings as the national standard, numbered GB 55020-2021, to be implemented from April 1, 2022. It is applicable to the design, construction, acceptance, operation and maintenance of building water supply and drainage and water-saving projects. This specification integrates the scattered mandatory provisions in the current standard into a full text mandatory engineering construction specification.

Mandatory engineering construction specifications are divided into engineering project specifications and general technical specifications. The engineering project specification is a mandatory standard that takes the engineering project as the object and focuses on the five elements of project scale, layout, function, performance and key technical measures. It is to constrain the engineering project as a whole, define the constraint requirements for the project initiation, construction, operation and demolition stages, and ensure the effective implementation of national policies, the perfection of function and performance, and the quality level to meet the requirements. The general technical specification is a mandatory standard with the technical specialty as the object and the general technical requirements for planning, survey, measurement, design, construction, etc. as the main content. It is a constraint from the specific professional technology to avoid the repetition of the general technical requirements in the engineering project specifications, and at the same time to meet the government's regulatory needs. In the full text of the mandatory engineering construction specification system, the project specification is the backbone, and the general specification is the provision of common and general professional key technical measures for various projects.

After the implementation of this code, the mandatory provisions in articles 3.3.3, 3.3.16, 4.1.2, 4.2.3, 5.2.1, 9.2.7 and 10.2.1 of code for acceptance of construction quality of building water supply, drainage and heating engineering (GB50242-2002) are abolished. See the table below. Meanwhile, the process handover record, concealed acceptance record, pipeline identification, commissioning and acceptance are specified as mandatory requirements.

Serial number

Repealed provisions of article gb50242

Gb55020 alternative provisions

remarks

one

3.3.3 waterproof measures shall be taken if there are pipes passing through the outer walls of basements or underground structures. For buildings with strict waterproof requirements, flexible waterproof casing must be used.

8.1.8 waterproof measures shall be taken if there are pipes passing through the outer walls of basements or underground structures. For buildings with strict waterproof requirements, flexible waterproof casing must be used.

two

3.3.16 various pressure bearing piping systems and equipment shall be subject to hydrostatic test, and non pressure bearing piping systems and equipment shall be subject to water filling test. 5.2.1 the concealed or buried drainage pipes must be subject to water filling test before concealment, and the water filling height shall not be lower than the upper edge of the bottom sanitary ware or the ground height of the bottom floor.

8.3.2 the water supply pipeline shall be put into operation after passing the hydrostatic test. Hydrostatic test shall include strength test and tightness test

Test requirements refer to Article descriptions

three

4.1.2 the water supply pipeline must adopt pipe fittings suitable for pipes, and the materials involved in the domestic water supply system must meet the sanitary standards for drinking water.

8.1.3 the aquatic products of the drinking water system shall meet the health and safety requirements.

four

4.2.3 the domestic water supply system pipes must be washed and disinfected before being delivered for use, and can only be used after being sampled and inspected by relevant departments and meeting the national standard for drinking water. Inspection method: check the inspection report provided by relevant departments; 9.2.7 after the completion of the water supply pipeline, the pipeline must be flushed, and the drinking water pipeline must be disinfected after flushing to meet the sanitary requirements of drinking water.

8.3.7 the pipes and equipment of domestic water supply, hot water system and swimming pool circulating water supply system must be flushed and disinfected before being delivered for use. The water quality of domestic and drinking water system shall be subject to witness sampling inspection, and the water quality shall comply with the provisions of the current national standard sanitary standard for drinking water GB5749

The new regulation requires witness sampling

five

10.2.1 the slope of the drainage pipeline must meet the design requirements. No slope or reverse slope is allowed.

8.2.2 the laying gradient of gravity drainage pipes must meet the design requirements. No slope or reverse slope is allowed.

The drainage gradient of cast iron pipe and plastic pipe is specified in the article description