Construction projects involve the co-ordination of a great number of people, materials and components. Regular inspection is a crucial part of ensuring that the works progress as intended, both in terms of quality and compliance. Inspections will be carried out for a number of different purposes throughout the duration of a project.
The inspection process is separate from the contractor’s own supervision of the works. Inspection is carried out purely to give an independent view of the works either for the client or a third party, the term supervision might imply taking some responsibility for the works, when in fact contractual responsibility lies with the contractor.
Quality and progress
Inspection of the construction works will be carried out as they proceed to verify compliance with the requirements of the contract documents.
Site inspectors (or clerks of works) may be provided as an additional service by the existing consultant team, or could be new appointments. They may be based on site permanently or may make regular visits. On large projects it may be appropriate to have separate site inspectors for mechanical and electrical services, structural works and architectural works. Specialist inspections may also be necessary for specific aspects of the project such as; the client’s environmental policy, site waste management plan, accessibility and so on.
Site inspectors provide an independent assessment of the works and will generally report to the contract administrator. They are likely to keep a site diary, attend construction progress meetings and to produce regular written reports.
Traditionally on the larger projects a clerk of works was appointed to be the eyes and ears of the consultants and be resident on site. They had limited power other than to inspect; they could condemn work but any instructions would be issued by the architect or the contract administrator.
Specific inspections may also be carried out during the construction phase as part of the general contract administration process:
Condition surveys of neighbouring structures prior to commencement of the works.
Regular valuation inspections to assess progress of the works in order to value interim payments.
Inspecting mock ups and samples and witnessing tests.
Inspection prior to certification of practical completion.
Inspection after handover of the site to the client on certification of practical completion.
Inspection at the end of the defects liability period to prepare a schedule of defects.
Inspection on completion of the rectification of defects set out on the schedule of defects.
Design consultants generally have a responsibility to provide periodic inspection under the terms of their conditions of engagement. However, the fact that it is periodic, and inspection not supervision, can relieve them of liability for specific workmanship defects that result in court action
Health and safety
Inspections are also necessary to ensure compliance with health and safety and CDM regulations. (Construction (Design and Management) Regulations). These can be internal inspections carried out by the contractor, third party audits or external inspections by the Health and Safety Executive.
The CDM regulations themselves only specifically mention inspection in relation to excavations, cofferdams and caissons (and any work equipment and materials which affect their safety), however other health and safety inspections may be necessary in relation to:
- Prevention of falls and personal fall protection systems.
- Work at height.
- Work platforms such as scaffold and mobile platforms.
- Ladders and stepladders.
- Personal protection equipment, including head protection.
- Plant, vehicles and other equipment.
- Electrical systems.
- Asbestos risk.
- Provision of welfare facilities such as toilets and handwashing facilities.
- Site conditions and order.
- Avoidance of obstructions.
Management of respiratory risks.
- Structural stability.
- Prevention of unauthorised access to the site.
It is important that inspection timing and frequency is properly organised, that proper reports are prepared and that action is taken if necessary.
Inspection reports might contain the following information:
- Details of the person making the report.
- Details of the person the inspection was carried out for.
- Location of the inspection.
- Date and time of the inspection.
- Description of the nature of the inspection.
- Details of health and safety risks identified.
- Details of any action taken.
- Details of any further action required.
- Building control
Building control inspections are carried out to verify compliance with the building regulations. These can be carried out by a local authority building control inspector or by an approved inspector. Inspections may be required for:
- Excavations, before filling.
- Foundations before covering up.
- Damp proof course.
- New drains before covering up.
- Ground beams and steelwork.
- Roof construction.
Advance notice must be given to arrange these inspections.
Very small projects can obtain building regulations approval purely by inspection. This is a building notice application rather than a full plans application.
Other inspections might include:
- Planning inspections to verify compliance with planning permissions, conditions and obligations.
- Inspections by funding bodies for the release of money.
- Inspections by insurers.
- Highways Authority inspection and adoption of roads and sewers.
- Environmental Health Officer inspections related to pollution (mud, noise, smoke, water) and certain installations (such as drainage and kitchens).
- Fire Officer inspection of fire escapes, and for hazards, storage of certain materials and protection systems.
- Archaeological inspection of excavations.
- Factory inspectorate.
- Health and safety inspectors.
NB: In a submission to the Inquiry into the Construction of Edinburgh Schools in 2016, The Royal Incorporation of Architects in Scotland (RIAS) criticised the transfer of responsibility from construction professionals to other parties less involved with the design process and sited the dilution of the role of the design team as one of the causes of poor quality construction. See Inquiry into the construction of Edinburgh schools view of the RIAS for more information.