ABSTRACT
The research was carried out to appraise contractors' prequalification criteria used by public organizations for building projects, for the last six years (2006-2011). Field survey involving ten public organizations in Kaduna was conducted. Data were collected with the aid of structured questionnaires. 60 questionnaires were distributed to construction professionals/ staff of which 55 responses were returned and 50 used for analysis. Information gathered include the major contractors' prequalification criteria and the sub contractors' prequalification criteria used to asses contractors on building construction works. The relative importance index (RII) was used to compute the mean score of the contractors Prequalification criteria in relation to the overall responses on a criterion were calculated. The research discovered that technical capacity with over 58% of the professionals considered it important among the major prequalification criteria. Health and safety is not appreciated, only 4% of the professionals considered it important. 'Similar projects executed' among the sub contractors' prequalification criteria, with over 60% responses considered it very important and Experience Modification Rating with only 8% responses considered it very important. The study further collected data from 30 contractors' prequalification check lists of completed public building projects. This was to check the significant agreement between percentage score allocation to the criteria. Kendall's test of coefficient of concordance, was used to compare ranking of common variables with score rate allocation obtained from sum scores. The result shows W value of 0.14 and test of significant of 16.15 agreement, which means, there is significant agreement in some percentage score allocation to criteria from the public organizations. Public organizations placed less emphasis on some contractors' prequalification criteria on the checklist. The study recommends that, professionals/ staff should aspire to understand, adopt and implement the requirements of contractors' prequalification criteria of building works. The public organizations should standardize respective building construction prequalification practices in putting into consideration all criteria on contractors' prequalification checklist with percentage score allocation to each criterion.