Why buildings are collapsing in high numbers

Debris of a five-storey building that collapsed in Ruaka, Kiambu County in May 2018. [Willis Awandu, Standard]

Shortcuts, poor workmanship, and impunity during construction are the leading causes of the collapsing of multi-storey buildings in the country, experts have told The Standard.

At least four apartments have, in the last two weeks, collapsed in Kiambu and Nairobi counties, resulting in the loss of lives and property valued at millions of shillings.

Questions have since arisen on the structural integrity of buildings being erected in the country, especially recently.

Property developers seem to capitalise on the housing shortage in the country to hastily and incautiously erect buildings for occupancy, hoping to recoup their investment as quickly as possible.

According to the World Bank, Kenya has a housing deficit of at least two million houses, which increases by around 200,000 units every year.

It is this business opportunity that has seen millionaire investors pump in their money, with the hope of getting good returns on investment.

Whereas a significant number follow the right channels in putting up their commercial structures, some opt for shortcuts and substandard building materials and labour to quickly finish their projects, ignoring the danger such decisions pose to innocent Kenyans.

Experts who spoke to The Standard said many apartment owners follow the right procedures when starting construction, only to employ poorly trained construction engineers and workers after getting the requisite permits.

Engineer Patrick Simiyu, who is the chairperson of the Association of Consulting Engineers (ACE), says there's an influx of quacks and ill-trained construction workers in Kenya's building and construction sector.

Simiyu says that poorly trained workers often expose constructions to non-compliance with building standards.

At the same time, Simiyu says that developers bent on saving too much money at the expense of quality workmanship are also to blame for the recent spike in the number of collapsed buildings.

A 2022 audit report by the National Construction Authority (NCA) on the collapse of buildings in Kenya places the blame on poor workmanship and non-compliance to standards.

The report says 10,791 out of 14,895 buildings were marked as unsafe for occupancy and needed either reinforcement or demolition.

"Kenya has recorded 87 building collapses over the past five years, while an estimated 200 people have lost their lives in the last five years, and over 1,000 injured as a result," said NCA in the report.

"Notably, 65 per cent of collapsed buildings were residential, while 25 per cent were commercial, 10 per cent were mixed-use developments," said the regulator.

The NCA report further revealed that 66 per cent of the buildings collapsed after completion, while 34 per cent collapsed during construction.

Engineer Patrick Simiyu, during an interview on Spice FM on Tuesday, November 22, said building owners have the tendency of engaging professionals at the start of construction, only to assign the projects to quacks at later stages.

"It's not a must that the person designing and approving the construction should be the one supervising the project to completion. Some building owners, while applying for approvals at the county level, seek the services of certified engineers and qualified architects. However, after securing the approvals, they opt for people with street experience to start the construction, all this in the name of cutting on costs," Engineer Simiyu said.

Hussein Abdi, an architect in Nairobi who has designed several floor plans of buildings in Eastleigh and Parklands, said that some property owners defy the original plans, and increase units that had not been factored in planning.

"You will, for instance, get someone constructing an eight-storey building on a five-storey building plan approved by the county authorities. When one stretches the limits of the foundation, for sure it will give in someday, and the entire structure will tumble down," said Abdi, clarifying that the architects' work ends at the floorplan.

Engineer David Njau spotlighted the quality of building materials used in the construction of major structures today.

"Many property owners, out of the desire to cut on construction costs, opt for cheaper, and usually sub-standard, building materials like cement, steel, sand, and binding wire," said Njau.

A March 2019 report by the BBC mentioned six key reasons why buildings collapse. The reasons are weak foundations, weak building materials, workers' mistakes, heavier than allowed loads, lack of strength assessment and people staying in condemned buildings.

The process of construction in Kenya starts with engaging an architect, who draws a floorplan.

The second stage is seeking construction approval from the relevant authorities, including the planning agency, and public health department, among others.

The planning team checks the zone in which your building is being constructed. There are industrial, central business district, residential and school zones.

The public health department, on the other hand, checks ventilation, lighting, sanitation, source of water, waste management and fire.

The National Environmental Management Authority (NEMA) will, thereafter, consolidate the reports and countercheck for compliance.

If NEMA approves the plan, a structural engineer can, thereafter, be assigned to the construction.

"The structural engineer has to work hand in hand with a geotechnical engineer, who examines the soil and advises the type of foundation needed for the proposed structure," Engineer Patrick Simiyu said on Spice FM on Tuesday.

In case a building collapses, the owner of the project is taken into custody as the investigation into whether he or she evaded rightful procedures continues.