Experts warn proliferation of substandard soil tests threatens building safety in Nigeria

In Nigeria, professionals are sounding alarms over the widespread practice of substandard and fraudulent soil testing in the housing sector. Kunle Awobodu, the Immediate Past President of the Nigeria Institute of Building (NIOB), has criticized what he sees as a proliferation of cheap, fake, or poorly executed soil tests, contending that these undermine foundation design and contribute to structural failures and building collapses. Data cited from Building Collapse Prevention Guild (BCPG) are showing that over 508 buildings collapsed across Nigeria, with 320 in Lagos State alone, between 1974 and mid-2022.

Specific malpractices he cited include:

• Use of uncalibrated Cone Penetration Test (CPT) or Standard Penetration Test (SPT) instruments
• Fabrication of “N-values” (SPT blow counts) rather than performing actual tests
• Skipping undisturbed sampling in cohesive soils
• Insufficient or superficial laboratory testing (e.g. for compaction, triaxial shear, Atterberg limits)
• Rushed or superficially supervised fieldwork, sometimes completing a borehole in one or two days when proper investigation might require three or four days

Awobodu further criticized the lack of institutional oversight. In his view, many states allow materials testing laboratories to both operate and regulate themselves, which can enable lower standards. He also asserted that unregulated entry into the soil test business allows unscrupulous operators to undercut reputable firms, ultimately compromising the quality and credibility of geotechnical data.

To address the problem, Awobodu recommended the following measures:

• A rigorous accreditation and certification framework for drillers and soil test laboratories
• Mandatory supervision of soil testing protocols by qualified geotechnical engineers
• Professional sanctions against those who sign off on unverified or faulty reports
• Public awareness campaigns to discourage clients from accepting substandard soil tests
• Strengthened enforcement by regulatory agencies such as state physical planning commissions and universities to secure integrity in geotechnical investigations