Approved Inspectors are private sector companies who have been approved by government to provide building control services. Approved Inspectors are governed by the Building Act and related regulations and government issued procedural guidance. As a result the general format of building control services is the same for Approved Inspectors and Local Authority Building Control.

Approved Inspectors functions are primarily governed by the Building Act and the Approved (Inspectors etc.) Regulations. This legal framework was first developed in the 1984 Building Act, and the first approved inspector to be approved and registered was the NHBC in 1985. Since 1997 the regulations were further developed and additional approved inspectors have been registered.

Local Authority Building Control functions are primarily governed by the Building Act and the Building Regulations.

As a result of the implementation of approved inspectors and private sector building control the way building control is provided is ever changing. This is mainly driven by the desire of approved inspectors to provide a professional service and ensure compliance, whilst maintaining a practical and reasonable approach.