A two-day inspection initiative of basement projects in homes of high-value west London boroughs was carried out by the Health and Safety Executive (HSE).

Construction inspectors carried out the inspection blitz on sites in Kensington and Chelsea, and Hammersmith and Fulham on March 9 and 10 in a bid to improve safety in the increasingly popular basement sector.

It follows a number a number of fatal incidents, as well as serious injuries, in the capital in recent years relating to basement projects.

Over the last 10 years, HSE has received reports of 17 construction workers having died as a result of an excavation collapsing, while in the same period 27 were seriously injured.

In December 2014, following the death of a labourer in a basement excavation collapse in Fulham, a company director was found guilty of manslaughter offences and jailed.

Inspection teams looked at key safety issues including collapsing excavations, risk of building collapse from structural alterations or undermining by excavating, the dangers of handling heavy steel beams, poor access and risks of open or unprotected parts of sites.

Other issues, such as poor welfare facilities and lack of training, can also result in HSE action if found.

HSE construction inspector James Hickman, whose team covers south-west London, said: “The construction of basements in London is increasingly widespread. Often it is carried out under existing homes as owners seek to increase their living space without a house move.

“The work is technically challenging and can carry substantial risk. Standards are often poor and often vulnerable sections of the labour market are recruited.

“Contractors are failing to appoint a competent temporary works engineer to design suitable propping to support excavations and existing structures. Likewise, on many projects basic safeguards are missing, such as edge protection to prevent falls from height. And all too often little thought is given to providing proper welfare facilities for site workers.

“Where we find poor practice that is putting lives at risk we will take action, including stopping work and prosecuting those responsible.”

The targeted inspection was part of continuing efforts by HSE to improve health and safety in this sector of the construction industry.