By Kingsley Adegboye
Completing abandoned uncompleted buildings for habitation carries major safety and financial implications, including structural degradation and high renovation costs. To ensure the buildings are safe for use after their completion, the issue of structural degradation and others must be adequately addressed, according to construction experts.
Reacting to the issue, Kunle Awobodu, former president of Nigerian Institute of Building (NIOB), and pioneer president of Building Collapse Prevention Guild (BCPG), said: “A building left under construction and exposed to rainfall and other weather conditions for several years is susceptible to significant deterioration.
“Prolonged exposure to moisture and atmospheric carbon dioxide accelerates the ‘carbonation’ process in concrete. This can result in reinforcement corrosion, concrete cracking, spalling, and a gradual reduction in the structural durability and service life of the building.”
In addition, Awobodu noted that prolonged weather exposure increases the water absorption of sandcrete blocks, which may reduce their strength and durability, particularly where poor-quality blocks were used.
Is the building safe for habitation?
According to him, “The safety of the building cannot be determined by visual inspection alone. A comprehensive building condition survey will be conducted to assess the extent of deterioration caused by prolonged exposure to weather.
“The survey should include: A detailed visual inspection of all structural and non-structural elements, non-destructive testing (NDT), to evaluate the in-situ condition and integrity of the concrete, assessment of carbonation depth and reinforcement corrosion where necessary, evaluation of the quality of construction, including workmanship and compliance with the approved structural drawings and relevant standards, and examination of the condition of sandcrete blocks, concrete members, and other structural components.
“The findings of the building survey, together with the recommendations of qualified professionals, particularly the Builder and Structural Engineer, will provide the basis for determining whether the building is safe for habitation, requires remedial works, strengthening, or, in extreme cases, partial or complete demolition,” Awobodu stated.
Building Collapse Prevention Guild
In his reaction, Arc. (Dr) Augustine Otuoke, an official of Building Collapse Prevention Guild, said: “Every abandoned building project is bound to be drastically affected by the elements of weather when abandoned in an unfinished state.
“When buildings are completed to practical completion/ habitation, the impact of external weather elements on the buildings are significantly reduced because of the finishes deployed and applied to all the building components, like roof, walls, windows, doors, and maintenance etc. This certainly will promote the lifespan of buildings.
“When buildings are abandoned in uncomplete forms, depending on the quality of construction, quality of construction materials used and the craftsman/skills of the builders, all the elements of weather will basically take their toll on the buildings by degrading and wearing their structural members, like columns, slabs, beams, etc.
“Even components of the structural members will be worn out with the reinforcements being exposed to rust stalling. Partition walls, roofs etc also wear out and lose their functionality. The consequences of abandonment is that the buildings become weak, brittle and obsolescent.
Neccessary tests
“All abandoned buildings must necessarily be subjected to the following test to determine the quality of their health and stability prior to any decision on them. They include integrity test/nondestructive test. This is to determine integrity and stability of the building’s structural systems. Probe of the foundation must be done. The reinforcements will have to be retested including the concrete etc.
“The lifespan of a building depending on the construction materials, whether, wood, bricks, masonry, sancdcrete, concrete, steel and stones is between 50 years to 500 years. Wooden buildings are about 50 years. Brick, masonry, blocks, concrete and steel buildings are between 50 years to 175 years. Stone buildings are between 100 years to 500 years. Maintenance (routine, minor, periodic, and turn-around maintenance) also add to lifespan of any building,” Otuoke said.
On his part, George Eromosele, a building engineer, said nondestructive test must be carried out on columns and beams of unroofed uncompleted abandoned buildings before completing them to habitable state because of long exposure to weather such as rains and sun, stressing that “without this integrity test, the safety of the buildings is not guaranteed after their completion.”
According to Eromosele, safety and structural risks of uncompleted abandoned buildings is a critical issue that must be taken serious when contemplating the completion of such buildings, pointing out that there could be foundation damage, soil shifts or water pooling can weaken the base over time.
He said there could be material decay leading to exposure of concrete, rebar, and wood rot from rain and sun exposure, adding that pest infestations by termites, rodents, or mold may have damaged hidden areas, just as outdated utilities such as old pipes and wiring which often fail modern safety codes.
The post Completing abandoned buildings for habitation carries major safety risks – Experts appeared first on Vanguard News.