A post-construction drain survey is a CCTV inspection carried out after building works have been completed to verify that the drainage system has not been damaged during construction. The survey compares findings against any earlier pre-construction drain survey baseline, identifying new defects such as cracked pipes, displaced joints or accumulated debris caused by site activity. In Greater London, the survey is widely used on basement conversions, rear extensions, side returns and new build projects close to existing drainage. Engineers carry out the inspection to BS EN 13508-2, grading defects against the WRc Manual of Sewer Condition Classification, and provide a written report alongside recorded footage. The output supports defects rectification, party wall settlement, Building Regulations Part H sign-off and adoption applications with Thames Water under Sewers for Adoption.
Post-construction drain survey
CCTV inspection after construction to verify drainage has not been damaged by works.
