Building control inspects a basement at agreed stages, including relevant structural work, drainage and work that will later be concealed. The inspection programme needs to be arranged before construction, and it does not replace the engineer's checks or the contractor's responsibility for compliant work. [1] [2]
Choose and brief the building control body
For ordinary non-higher-risk work, the route can be through local authority building control or a registered building control approver. Different arrangements apply where the work falls within the Building Safety Regulator's higher-risk building regime. Establish the correct route rather than assuming every basement uses the same procedure. [3]
Provide the coordinated building regulations drawings, structural design and relevant technical information. A planning drawing does not necessarily show the construction details needed to assess the work. Basement guidance identifies structure, damp protection, fire escape, drainage and ventilation among the matters requiring attention. [4]
Agree the stages that must remain visible
Ask for an inspection plan matched to the construction method. For underpinning, LABC explains that sections need inspection before concrete is placed. The contractor must allow for those points instead of completing and covering the work before an inspector can see it. [1]
Also identify when drainage, structural connections, waterproofing interfaces, insulation and fire-protection work will be accessible for the relevant checks. The precise visits depend on the design and building control body's inspection plan; this is not a fixed national list of basement visits. [5] [2]
Separate the different inspections
Building control considers compliance with the Building Regulations. The structural engineer may have separately appointed inspections, while waterproofing specialists need to check their system's installation and commissioning. Confirm those appointments rather than assuming one visit will cover everything. [2] [6]
Temporary works and excavation safety need their own competent supervision and inspections. HSE describes checks at the start of a shift and following events affecting an excavation's stability. A building control visit is not a replacement for those site-safety duties. [7]
Do not cover unresolved work
Ask the contractor to identify inspection and approval points in the programme and name the person responsible for booking them. If work is about to be concealed without the required check, resolve the position with the building control body first. LABC's underpinning guidance specifically makes inspection before concrete part of the process. [1]
Where the actual ground or structure differs from the drawings, obtain the responsible designer's assessment and revised details as necessary. Continuing to build from an assumption already disproved on site is inconsistent with maintaining a safe and coordinated design. [8] [2]
Completion and records
Arrange the final inspection and submit the required completion information and dutyholder declarations. Newham's published building control guidance explains the declaration requirements; finishing the decoration alone does not close the building control process. [9]
Keep the inspection correspondence, final design information and applicable completion documentation together with the waterproofing maintenance information. The latter remains important after the building control process ends. [9] [10]
Revised energy and ventilation provisions take effect for relevant work from 24 March 2027, subject to transition. Establish the applicable standards at application stage; the new-home Future Homes Standard should not be mistaken for a blanket requirement to rebuild every existing basement. [11]