Common Causes Of Building Collapse In Ghana

Collapse of buildings in recent times have become very alarming in the country.

This has resulted in the killing of innocent people, infringing permanent disability to many and destroying properties. It also comes as a huge cost to the state through the clearing of debris and rescuing survivors.

Between 2012 and 2014, Accra the capital city of Ghana officially recorded four major building collapse claiming a total of 19 lives. The Melcom building collapse near Achimota in 2012 claimed 14 lives whereas the Grand view Hotel building collapse at Nii-Boi town in 2014 recorded four deaths. Two other buildings collapsed in 2014; the building near Akai house at Cantonments claimed one life whereas the Central University hostel building collapse in Dawhenya recorded no death. Recently, there was another multi-storey building collapse in Cantonment that recorded three deaths. A critical review of these buildings showed that almost all buildings that collapsed within this period were privately owned properties.

Buildings in general serve many purposes including provision of shelter for man, protecting properties, and other activities. With these purposes that buildings provide, there is always the need to properly plan, design and construct buildings to obtain expected satisfaction from the environment and prevent building collapse. Collapse of buildings is the worse form of structural failure and building professionals see it as building failure of higher magnitude. Therefore efforts should be made to minimize building collapse. History has recorded that during the Babylonian era many years ago, collapse of buildings attracted severe punishment including execution of craftsmen. This showed how the early Babylonian kingdom attached great importance to prevent collapse of buildings.

Every building can collapse but multi-storey structures are more prone to collapse of higher magnitude. Multi-storey buildings may collapse when there is structural failure. Structural collapse may be unique with every building, however the reasons why a building will collapse could generally be attributed to either a natural or man-made infrastructural disasters. For natural disasters such as typhoons, cyclones, tsunamis, earthquake, and many more, Ghana is blessed as a nation not to be experiencing any of these. The man-made disasters are born out of man’s negligence. In Ghana, almost all structural failures could be attributed to man-made phenomena. These man-made phenomena noticeable and very common in our construction industry that usually contributes to structural failure include lack of soil type investigation, poor building design and planning, use of inferior or sub-standard building materials, weak supervision, use of incompetent contractors, and lack of enforcement of building standards and codes.

The soil type which holds an infrastructure is a critical area one needs to investigate before building any multi-storey structure. This is important because it provides information on the soil bearing capacity. Every building carries a specific load that needs to be safely transferred to the ground via the foundation. It is unfortunate that in Ghana, many private owners may not know this and therefore never perform any soil test. Accra is very critical due to the soil composition and properties as well as its seismic properties

Poor building design and planning contributes significantly to collapse of multi-story buildings. At the design and planning stage, building professionals including architects and structural engineers perform detailed calculations to ensure a sustainable structural integrity of the building. In cases of wrong calculations from any of the professionals, a multi-storey structure may collapse from varying reasons including excess load exerted on supporting pillars of the building. In Accra, now it is a requirement to provide structural calculations and integrity reports on any multi-storey buildings, but this is yet to achieve full enforcement

The use of inferior and sub-standard building materials play a major role in collapse of buildings. Low strength of mortar, concrete and sandcrete blocks may not be able to withstand dead and live loads that come with multi-storey buildings. It is even worse with commercial sandcrete blocks and concrete manufacturers who always want to make outrageous profit at the expense of product quality.

Weak supervision and the use of incompetent contractors may also lead to the collapse of multi-storey buildings. The construction stage of a multi-storey building is the stage that needs effective supervision because of inadequate skills and knowledge among masons. A good design may fail when clients fail to secure competent professionals to oversee the construction stage. Most clients are interested in the building approval stage and not the aftermath. Thus they do away with professionals when approvals are given by authorities. A contractor who lacks the requisite skills and is very ignorant on construction skills may have a negative impact on either the pre and post construction stage of multi-storey buildings.

Lastly, a building may collapse when there is gross disregard for building regulations, codes and standards. Currently in Ghana, many private developers have developed an appetite to get returns on their investments in building projects. As such, developers build without the required approval from state institutions because of perceived weak state institutions, bribery and corruption as well as political interferences from ruling governments. State institutions on the other hand, have failed woefully in carrying out effective monitoring mechanisms on buildings especially multi-storey structures.

It would be recommended that as a way-forward in preventing future collapse, proper education may periodically be given to masons and contractors on some common causes of building collapse. Moreover state authorities mandated to monitor building projects in the country should make sure that builders abide by certain accepted standards. Failure on the part of mandated institutions must be held responsible and accountable by government. They must also pull down unauthorized structures and severely punish developers who go contrary to strict building rules of the land.

It is also recommended that Accra Metropolitan Authority (AMA) sublet the supervision of certain multi-storey structures to professional bodies such as Ghana Institution of Engineers (GhIE), Ghana Institution of Architects, etc who would form taskforce to make sure that sanity is prevailed in the construction of such buildings.

By
Mark Bediako
Research Scientist
csir-building and road research institute
email: [email protected]