Project Control Mechanisms and the Performance of Affordable Housing Projects in Nairobi City County, Kenya

Government affordable housing projects in Nairobi County continue to record delays, cost overruns, and uneven construction quality despite substantial public investment under the Affordable Housing Programme. This article examines how project control mechanisms scheduling and milestone definition, cost monitoring, quality assurance, monitoring and evaluation, regulatory oversight, reporting and supervision, and accountability systems relate to the performance of these projects. Using a descriptive mixed-methods design, structured questionnaires were administered to a sample of 234 respondents drawn from a target population of 600 project managers, housing officials, contractors, site engineers, consultants, and beneficiaries, of which 197 were returned (84.2% response rate). Twenty key informants were interviewed. Descriptive statistics were computed in SPSS v29, and interview data were analysed thematically. Project control mechanisms recorded an overall composite mean of 3.52 (SD = 1.35), indicating that control practices are generally in place. Strongest performance was recorded for regulatory oversight (mean 4.14), accountability mechanisms (4.12), formal monitoring and evaluation frameworks (4.03), and pre implementation scheduling (4.01). Weakest performance was recorded for reporting and supervision structures (2.46), documented quality assurance and correction of non-conforming work (2.61) and budget variance analysis (3.10). Against these controls, project performance was mixed: affordability (3.99) and local employment creation (3.88) scored well, while timely completion (2.01), delay minimisation (2.16) and budget adherence (2.28) scored poorly. The article argues that the control architecture in Nairobi's affordable housing projects is strong at the level of formal frameworks but weak at the level of routine execution, and that this gap explains the persistence of schedule and cost failure alongside apparently robust governance. Keywords: project control, monitoring and evaluation, quality assurance, affordable housing, project performance, Nairobi County, Kenya