Unsafe instructions from a building inspector

This report sadly reflects what CROSS hears too often - concerns about the lack of competency of some people involved in construction processes. In this case, to receive a report that a chartered engineer performing as a building inspector did not recognise obvious personal safety and building instability risks is grossly concerning. The reported actions of the contractor blindly following ‘instructions’ from the building inspector compound the concerns. The contractor's first duty is to protect life and not to please a building inspector.

Health and Safety legislation places duties on individuals as well as companies to ensure that they don’t put people at risk of harm. In the most serious of cases, and where a death results, this can amount to gross negligence manslaughter. There have been cases where, following collapse, individuals have been prosecuted. Some years ago, there was a case where a designer (an experienced engineer) agreed to a contractor excavating a trench alongside a wall to a depth 900mm deeper than the base of the wall. The wall slid into the excavation killing two workers. The charge of manslaughter by gross negligence was laid against the individual who was an employee.

In the circumstances described by the reporter, had an operative entered the trench and been killed by a collapse, any party that ignored a clear and obvious risk of death would likely be investigated and possibly face charges relating to manslaughter. Penalties can include prison sentences, let alone knowing that your negligence has led to a fatality. 

It appears that there was a lack of understanding of the role performed by building control. A building inspector cannot instruct anything. They are not a party to any normal building contract and have no authority to instruct. They can as part of their duties request that something is done to facilitate their inspections, and it is down to the contractor to enable this in a safe way. They can also state that something is non-compliant with the building regulations, but again it is down to the contractors or designers to correct this in a suitable way. Contractors should refuse to do anything they feel is unsafe, but ensure they enable building control inspections.

This report raises at least two very significant risks to life; the collapse of unsupported excavations onto anyone in the excavation and the collapse of existing structures adjacent to the excavations. Many garden or boundary walls, let alone retaining walls, have very shallow foundations which are easily undermined by even small trenches. The picture painted of a 1.8m vertical excavated face to the exposed edge of a concrete raft supporting a house defies belief. For excavations 1.8m deep, appropriate support to the excavated faces was required. The Health and Safety Executive (HSE) provide extensive guidance upon excavations including ‘Excavations What you need to know’.

The designer of the extension should have been thinking about the foundations of the existing building and had the designer uncovered the fact that the building was founded on a raft, that may have started a deeper examination of what foundations are likely to be required for the extension. Indeed, a structural engineer would likely have been called in to assess foundation requirements. Proper site and soil investigations would probably have led to the project progressing without the severe safety risks that unfolded. Money and time spent on investigations, even for smaller projects, is invariably money and time well spent.

In that the neighbour’s retaining wall was apparently undermined, agreement under the Party Wall Act 1996 may have been required. Again, this was a missed opportunity to start the project well; a building professional dealing with party wall matters may have highlighted acceptable excavation depths to avoid undermining the retaining wall.