Building Control inspectors are appointed either by the local authority or as private Approved Inspectors to ensure that building work complies with the building regulations. They visit the site at key stages of construction to inspect the work before it is covered up or completed. Understanding when inspections happen and what inspectors look for helps you and your contractor ensure the project passes first time.
The frequency and type of inspections depends on the type and scale of the project. For a typical house extension, inspections are typically required at the following stages: commencement, which is the first inspection to confirm work has started and that the inspector has the site address; excavations, which must be inspected before concrete is poured so the inspector can check depth and ground conditions; foundations, inspected before the concrete is poured or the footing work is covered; damp proof course, inspected when the wall has reached damp proof course level; superstructure, when the walls and structure are progressing; roof structure, when the new roof is framed but before it is covered; insulation and airtightness, before plasterboard is fixed; and completion, when all work is finished.
For a loft conversion, additional inspections may be required for the structural floor system, the fire-rated lining of the new staircase enclosure, and the escape window.
The inspector will check that the work being carried out matches the approved drawings and specification, that the materials used are appropriate, and that the construction methods comply with the relevant parts of the building regulations. If an inspector finds work that does not comply, they will raise a notice requiring the contractor to remedy the issue before the inspection is passed.
The most common reasons for failed inspections include foundations that do not extend to the required depth, damp proof course that is incorrectly positioned relative to finished ground level, structural elements that do not match the engineer drawings, and insulation that does not meet the specified U-values. A competent contractor knows what inspectors look for and ensures the work is ready before requesting an inspection.
RCB Design and Build coordinates all Building Control inspections as part of our project management service, and we brief our teams on what is required at each inspection stage to ensure a smooth process from start to completion certificate.