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The Impact of Cost–Benefit Analysis on the Development of
Residential Construction Projects in Sub-Saharan African
Countries: A PRISMA-Guided Systematic Empirical Review (2010 –
2025)
Kelvin Felix Kisaka¹, Josephat Bernard Delli¹, Lameck Baya¹, Fanuel Mbwagha¹ & Tazamael J.
Akyoo¹
¹Department of Engineering, Mtwara Campus College of Technical Education, Mbeya University of
Science and Technology, Tanzania
DOI: https://doi.org/10.51583/IJLTEMAS.2026.150500288
Received: 27 May 2026; Accepted: 01 June 2026; Published: 29 June 2026
ABSTRACT
The use of cost-benefit analysis (CBA) in residential construction development across Sub-Saharan Africa (SSA) is an
area of empirical inquiry that is important yet not cohesively synthesized. With rapid urbanization, housing deficits
estimated at over 51 million units, and growing infrastructure investment needs, the evidence on CBA's value as a
decision-support tool in SSA's residential sector remains fragmented and locally bounded. This systematic review,
guided by PRISMA protocols, consolidates findings from 47 empirical studies published between 2010 and 2025,
sourced from Google Scholar, Scopus, SciSpace, and PubMed.
It assesses how CBA shapes project feasibility, financial viability, social cost incorporation, environmental externality
valuation, and policy-informed investment decisions in SSA residential construction. The findings indicate that CBA
adoption enhances investment efficiency and risk management, yet significant methodological obstacles remain,
particularly data scarcity, informal land tenure, challenges with shadow pricing, and systematic undervaluation of social
and environmental costs.
The review identifies the theoretical foundations that inform CBA practice, maps the empirical evidence on financial
and socioeconomic returns, and pinpoints region-specific constraints that undermine CBA's predictive accuracy. It
concludes with policy recommendations and directions for future research, emphasizing the need for context-sensitive
CBA frameworks, professional capacity development among built environment practitioners, and the incorporation of
sustainability cost metrics into standard appraisal practice across SSA.
Keywords: cost–benefit analysis, residential construction, Sub-Saharan Africa, housing development, project appraisal,
urban housing deficit, PRISMA systematic review, construction economics, affordable housing
INTRODUCTION
Background and Rationale
Sub-Saharan Africa (SSA) confronts one of the most acute housing deficits in the world, driven by exponential
population growth, rapid rural-to-urban migration, and persistent structural inadequacies in construction
financing and land governance. By 2025, the region's urban population had surpassed 600 million, with
projections indicating that Africa will house approximately 1.5 billion urban dwellers by 2050, the majority
of whom reside or will reside in informal settlements characterised
by substandard shelter, inadequate infrastructure, and limited access to essential services (UN-Habitat, 2023).
Against this backdrop, the allocation of public and private resources to residential construction projects
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demands rigorous appraisal mechanisms capable of evaluating the true economic, social, and environmental
worth of proposed developments.
Cost–Benefit Analysis (CBA) constitutes one of the most widely applied decision-support tools in
infrastructure and construction economics globally. Rooted in welfare economics, CBA systematically
quantifies and compares the monetary value of all anticipated benefits and costs of a project over its lifecycle,
thereby enabling informed investment decisions that maximise net social welfare (Boardman et al., 2018). In
the residential construction sector, CBA is employed across feasibility assessment, financial viability
modelling, social housing policy appraisal, and environmental impact valuation. Its application spans both
public-sector housing programmes and private-sector real estate development, where it serves as a basis for
project approval, financing, and regulatory compliance.
In spite of its theoretical robustness and growing international adoption, the empirical evidence on how CBA
shapes residential construction project outcomes across SSA remains fragmented, geographically skewed
toward a few countries such as South Africa, Ghana, and Nigeria, and methodologically heterogeneous. A
number of structural challenges peculiar to SSA constrain effective CBA application: pervasive informal land
markets, unreliable construction cost databases, weak regulatory enforcement, limited institutional capacity
among built environment professionals, and the difficulty of monetising social and environmental benefits in
contexts of extreme poverty (Akintoye et al., 2020). Consequently, CBA exercises in SSA frequently rely on
shadow pricing, proxy indicators, and cross-contextual data transfers that may misrepresent local conditions
and generate unreliable appraisal outcomes.
The existing literature also reveals a significant disconnect between CBA theory and practice in SSA.
Practitioners operating in government agencies, development finance institutions, and private construction
firms often deploy abbreviated or informal CBA processes that fail to capture the full range of project
externalities, particularly in social housing and affordable housing developments where community welfare
effects are paramount (Osei-Kyei & Chan, 2017). This gap between methodological standards and field
realities has contributed to numerous cases of housing project cost overruns, financial insolvency, and the
delivery of units that are unaffordable to the intended beneficiary populations, outcomes that a well-conducted
CBA might have anticipated and mitigated.
This systematic review is therefore motivated by the need to consolidate the dispersed empirical evidence on
CBA's application in residential construction across SSA, identify the theoretical frameworks and analytical
methods most frequently employed, assess the documented impact of CBA on project performance and
socioeconomic outcomes, and delineate the contextual barriers that limit its effectiveness. By synthesising
evidence across 47 studies spanning 15 SSA countries and using the PRISMA 2020 framework, this review
contributes a foundational empirical resource for researchers, policymakers, development finance institutions,
and construction practitioners seeking to strengthen investment decision-making in Africa's rapidly expanding
residential construction sector.
Scope and Objectives
This review focuses exclusively on empirical studies examining the application, outcomes, and challenges of
CBA in residential construction project development across Sub-Saharan African countries, with publications
spanning 2010 to 2025. The following specific objectives guide the review:
• To identify and critically analyse the principal theoretical frameworks underpinning CBA application
in residential construction development within SSA contexts.
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• To synthesise empirical evidence on the relationship between CBA adoption and key project
development outcomes, including financial viability, cost control, social return, and environmental
compliance.
• To examine how CBA integrates social and environmental cost dimensions — including community
displacement, infrastructure externalities, and ecological impacts — in residential project appraisals
across SSA.
• To determine the methodological challenges, data limitations, and institutional barriers that constrain
rigorous CBA application in the SSA residential construction sector.
• To provide evidence-based policy recommendations and future research directions that strengthen
CBA practice and housing investment decision-making across Sub-Saharan Africa.
Research Questions
This review addresses the following research questions:
• What theoretical frameworks dominate the application of CBA in residential construction project
appraisal across SSA, and how are they operationalised in empirical research?
• In what ways does CBA influence financial viability assessment, project feasibility outcomes, and
investment risk management in SSA residential construction contexts?
• How are social costs and benefits, including housing affordability, employment generation, and
community wellbeing, incorporated into CBA frameworks applied to SSA residential projects?
• What methodological constraints and institutional capacity gaps most significantly limit the reliability
and effectiveness of CBA in Sub-Saharan African residential construction?
What contextual factors unique to Sub-Saharan Africa, including land tenure systems, informal economies,
climate risk, and regulatory environments, moderate the relationship between CBA application and residential
project success?
METHODOLOGY
PRISMA Protocol
This systematic literature review adheres to the PRISMA 2020 (Preferred Reporting Items for Systematic
Reviews and Meta-Analyses) guidelines to ensure transparency, reproducibility, and rigour in the
identification, screening, eligibility assessment, and synthesis of empirical studies (Page et al., 2021).
The PRISMA protocol was selected as the methodological standard because of its international recognition in
systematic review methodology, its applicability to non-medical research fields including built environment
and construction economics, and its structured provisions for minimising selection bias and reporting
inconsistencies (Haddaway et al., 2022).
The review protocol was prospectively planned, and all inclusion and exclusion decisions were made against
pre-defined criteria prior to the commencement of the screening process.
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Search Strategy
A comprehensive search strategy was implemented across multiple scholarly databases, including SciSpace,
Google Scholar, Scopus, PubMed Central, African Journals Online (AJOL), and the World Bank Open
Knowledge Repository, to maximise coverage of both international and region-specific empirical literature.
Institutional repositories of key African universities, including the University of Cape Town, University of
Ghana, and University of Lagos, were also searched. Grey literature including working papers, government
housing policy reports, and World Bank project evaluation documents was incorporated where peer-reviewed
evidence was limited.
The search strategy employed Boolean operators to combine relevant terms and ensure comprehensive
coverage of the literature. Primary search strings included ("Cost-Benefit Analysis" OR "CBA" OR "cost-
benefit appraisal" OR "project appraisal") AND ("residential construction" OR "housing development" OR
"real estate development" OR "affordable housing" OR "social housing"). AND ("Sub-Saharan Africa" OR
"Africa" OR specific country names including Ghana, Nigeria, Kenya, South Africa, Ethiopia, Tanzania,
Zambia, Uganda, Cameroon, Senegal, Mozambique, Namibia, Rwanda, Côte d'Ivoire, Zimbabwe). Searches
were limited to studies published in English or Portuguese with English abstracts.
Inclusion and Exclusion Criteria
Inclusion criteria:
Empirical studies (quantitative, qualitative, or mixed-methods) examining the application or impact of CBA
in residential or affordable housing construction project development within SSA countries; peer-reviewed
journal articles, conference proceedings, and institutional working papers; publications between January 2010
and December 2025; studies addressing at least one dimension of CBA (financial appraisal, social cost-
benefit, environmental valuation, or lifecycle cost analysis) in the residential construction context; and studies
with discernible methodological descriptions and data from SSA country contexts.
Exclusion criteria:
Purely theoretical or conceptual papers without empirical data; studies conducted exclusively outside SSA;
publications before 2010; studies examining CBA exclusively in non-residential construction sectors (roads,
dams, industrial buildings) without relevance to the housing sector; duplicate publications reporting the same
empirical dataset; and studies with insufficient methodological description to assess quality.
Data Extraction and Synthesis
Following the search and screening process, 47 unique relevant studies were identified for inclusion in the
final synthesis. A structured data extraction template was applied to each included study, capturing the
following variables: author(s) and year; country and regional context; study design and methodology; sample
characteristics; CBA dimensions examined; key empirical findings; identified barriers or facilitators; and
study quality indicators.
Data extraction focused on theoretical frameworks employed; CBA methods applied (Net Present Value,
Benefit-Cost Ratio, Internal Rate of Return, and Social CBA); the nature of costs and benefits quantified;
project type and scale; funding sources; and outcomes in terms of project feasibility, financial performance,
social return, and environmental compliance. Two independent reviewers conducted data extraction, with
discrepancies resolved through discussion and reference to original texts. Quality assessment was conducted
using the Mixed Methods Appraisal Tool (MMAT), adapting criteria to the built environment research context.
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The synthesis approach combined narrative synthesis with structured comparison tables to identify patterns,
convergences, contradictions, and contextual variations across the included studies. Where sufficient data
were available, frequency analyses were conducted on CBA-related variables to map the relative prominence
of specific appraisal dimensions in the SSA literature.
Figure 1: PRISMA 2020 Flow Diagram Showing the Study Selection Process for CBA in SSA Residential
Construction (2010–2025)
Theoretical Literature Review
Welfare Economics and the Foundations of CBA
Cost–Benefit Analysis is grounded in the tradition of welfare economics, particularly the Kaldor-Hicks
efficiency criterion, which holds that a project is economically justifiable if the aggregate benefits to gainers
are sufficient to compensate losers — regardless of whether such compensation actually occurs (Boardman et
al., 2018). In the context of residential construction, this theoretical foundation means that a housing
development project is deemed worthwhile if the sum of all economic, social, and environmental benefits
(adequately monetised and discounted to present value) exceeds the sum of all direct and indirect costs over
the project's useful life. This framework provides the normative basis for public investment in social housing,
urban renewal, and infrastructure-linked residential development, all of which generate significant positive
externalities that private markets fail to price.
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In SSA contexts, welfare economics theory confronts distinctive challenges in the domain of housing. The
prevalence of dual economies, formal and informal, means that shadow prices frequently diverge from market
prices and that the opportunity costs of inputs such as labour, land, and capital are poorly reflected in standard
CBA calculations (Zerbe & Bellas, 2006). Theoretical adaptations proposed by researchers operating in
developing country contexts, particularly the work of Little and Mirrlees (1974) and the more recent
contributions of Adler and Norheim (2013), have argued for economy-wide shadow pricing systems that
adjust market prices to reflect true social scarcity values. However, the empirical literature from SSA reveals
that such adjustments are rarely operationalised in practice, creating a persistent gap between CBA's
theoretical rigour and its practical execution in residential construction appraisal.
Net Present Value and Discounted Cash Flow Theory
Net Present Value (NPV) analysis, a central component of CBA, rests on discounted cash flow (DCF) theory,
which recognises the time value of money and the uncertainty premium attached to future cash flows. In
residential construction, NPV is calculated by discounting all projected project revenues, including rental
income, property sale proceeds, and long-term community welfare gains, against projected costs, including
land acquisition, construction, infrastructure provision, operation, maintenance, and decommissioning, using
an appropriate discount rate reflective of the social opportunity cost of capital (Harberger, 1972).
The choice of discount rate is particularly consequential in SSA residential construction, where public housing
programmes must balance short-term fiscal constraints against long-term social welfare obligations. Studies
from South Africa and Kenya have noted the tendency of government agencies to apply commercially
determined discount rates to social housing CBA exercises, which systematically undervalues long-horizon
social benefits such as community stability, inter-generational housing security, and poverty reduction (Viruly
& Hopkins, 2019). The social discount rate debate with proponents of lower rates (2–4%) arguing that future
generations' welfare should not be heavily discounted, and proponents of higher rates (8–12%) emphasising
fiscal realism remains unresolved in SSA housing policy practice.
Social Cost-Benefit Analysis and Distributional Weighting
Social Cost-Benefit Analysis (SCBA) extends conventional CBA by explicitly incorporating distributional
weights that give greater value to benefits accruing to lower-income groups, acknowledging that a unit of
consumption is more valuable to a poor household than to a wealthy one (Layard & Glaister, 1994). In the
context of affordable and social housing development across SSA, SCBA is theoretically superior to
conventional CBA because the intended beneficiaries — low-income urban households — are precisely those
for whom distributional weights are most significant. The pioneering work of Pearce et al. (2006) on
distributional CBA has been applied in a number of donor-funded housing programmes in SSA, including
World Bank and African Development Bank-financed social housing schemes, though empirical evidence on
its practical adoption by domestic housing authorities remains sparse.
The integration of distributional weights into SSA housing CBAs also intersects with the theory of housing
affordability, which posits that residential construction serves a dual economic function: as a commodity
subject to market forces and as a basic right requiring redistributive public intervention (Erguden, 2001). CBA
frameworks that fail to explicitly weight benefits to low-income beneficiaries’ risk producing appraisal
outcomes that systematically favour commercially viable but socially exclusionary housing developments
exacerbating spatial inequality and urban segregation outcomes extensively documented in SSA cities
including Nairobi, Lagos, Accra, and Johannesburg(Parnell & Pieterse, 2014).
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Real Estate Development Theory and Financial Feasibility
Real estate development theory provides a complementary private-sector framework for understanding CBA
in residential construction. Drawing on the residual land value model and the developer's profit maximisation
calculus, this theoretical tradition conceptualises project feasibility as a function of the relationship between
revenue (determined by market-rate property prices or rental yields) and total development costs, including
land, construction, professional fees, finance charges, and developer profit margin (Cadman & Topping,
2009). When revenues exceed costs, the residual constitutes the maximum price a developer can pay for land
and still achieve target returns — a calculation that is fundamentally a private-sector form of CBA.
In SSA, real estate development theory intersects with CBA in the affordable housing sector, where the gap
between market-rate revenues and total development costs is often negative for low-income housing without
public subsidy. Empirical studies from Ghana, Nigeria, and South Africa have demonstrated that the financial
viability of affordable housing projects is contingent on land subsidies, tax incentives, or cross-subsidisation
from higher-income units – findings that directly implicate CBA in the design and justification of housing
subsidy schemes.
Public Choice Theory and Government Housing Investment
Public choice theory, developed by Buchanan and Tullock (1962), offers a political economy perspective on
CBA in public housing investment. It contends that government decision-makers, like private actors, respond
to incentives and information constraints and may deviate from CBA outcomes in favour of politically
motivated housing allocations, patronage-driven contract awards, or short-term electoral considerations. In
SSA, where governance challenges, corruption risks, and weak institutional accountability are documented
constraints on housing delivery, public choice theory provides an important explanatory lens for
understanding why CBA is frequently commissioned but selectively applied in residential construction project
decisions.
Empirical evidence from Kenya, Zimbabwe, and Tanzania reveals patterns consistent with public choice
predictions: government housing projects are occasionally approved despite negative net present values when
CBA findings align with political priorities, while financially viable projects are shelved when they conflict
with incumbent interests (Kirunda et al., 2021). This theoretical perspective, therefore, underscores the
importance of CBA institutionalisation, embedding CBA requirements in procurement regulations,
development finance agreements, and housing policy frameworks to insulate housing investment decisions
from purely political calculus.
Sustainable Development and Environmental Cost Valuation
The sustainable development paradigm operationalised in the United Nations Sustainable Development Goals
(SDGs), particularly SDG 11 on sustainable cities and communities, demands that residential construction
CBA integrate environmental cost dimensions, including carbon emissions, resource depletion, biodiversity
loss, and climate change vulnerability (UNEP, 2017). Environmental cost-benefit analysis, incorporating
techniques such as contingent valuation, hedonic pricing, and life-cycle cost assessment, extends the CBA
framework beyond financial and social costs to encompass ecological externalities that are particularly
pronounced in SSA where climate change disproportionately threatens urban infrastructure and low-lying
residential settlements.
The theoretical integration of environmental values into residential construction CBA in SSA remains nascent
but growing. Studies from South Africa, Ghana, and Rwanda have begun to quantify the cost of climate-
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induced housing damage, the benefit of green building standards, and the environmental cost of informal
settlement expansion into ecologically sensitive areas contributions that expand the CBA evidence base and
align with global sustainable finance frameworks(Ayarkwa et al., 2020; Giordano et al., 2022)
Table 1: Theoretical Frameworks Supporting CBA Application in SSA Residential Construction Research
Theoretical
Framework
Core Proposition
Application in SSA Housing
CBA
Key Scholars
Welfare Economics
(Kaldor-Hicks)
Projects justified if
aggregate benefits
exceed costs, enabling
potential compensation
of losers
Basis for public housing
investment appraisal and
subsidy justification in SSA
Boardman et al. (2018);
Zerbe & Bellas (2006)
Discounted Cash Flow
/ NPV Theory
Future values discounted
to present using social
opportunity cost of
capital
Applied in feasibility studies
for residential development;
contested discount rate
selection in SSA
Harberger (1972); Viruly
& Hopkins (2019)
Social CBA and
Distributional
Weighting
Benefits to low-income
groups given greater
weight to reflect
diminishing marginal
utility
Applied in World Bank/AfDB
social housing programmes;
underutilised in domestic SSA
practice
Pearce et al. (2006);
Layard & Glaister (1994)
Real Estate
Development Theory
Project viability
assessed via residual
land value; revenue must
exceed total
development cost plus
profit
Informs private developer
CBA; explains housing
affordability gap in SSA
Cadman & Topping
(2009); Awunyo-Vitor &
Atobrah (2020)
Public Choice Theory
Government decisions
respond to political
incentives, potentially
deviating from CBA-
optimal outcomes
Explains selective CBA
application in SSA public
housing; supports
institutionalisation of CBA
mandates
Buchanan & Tullock
(1962); Kirunda et al.
(2021)
Sustainable
Development /
Environmental CBA
Environmental
externalities must be
monetised and
incorporated into project
appraisal
Emerging in SSA through
green building CBA, climate
risk valuation, and lifecycle
cost studies
UNEP (2017); Ayarkwa
et al. (2020)
EMPIRICAL LITERATURE REVIEW
CBA and Project Feasibility Assessment
CBA's most consistently documented role in SSA residential construction is as a project feasibility instrument
used by development finance institutions, government housing agencies, and private developers to assess
whether proposed projects are economically and financially viable prior to investment commitment. Across
the reviewed studies, CBA was found to be a mandatory or strongly recommended component of project
approval processes in South Africa, Ghana, Kenya, and Nigeria, where national housing development agencies
and multilateral lenders have institutionalised pre-investment appraisal requirements (World Bank, 2022).
A comprehensive study of the National Housing Corporation's project appraisal practices in Tanzania revealed
that projects subjected to full CBA incorporating NPV, Benefit-Cost Ratio (BCR), and Internal Rate of Return
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(IRR) had significantly lower rates of cost overrun and project abandonment compared to projects approved
on the basis of financial feasibility studies alone (Mwita & Mselle, 2021). The Tanzanian evidence is
consistent with findings from Zambia, where the Urban and Rural Housing Authority reported that CBA-
appraised social housing projects achieved an average BCR of 1.34, while non-appraised projects frequently
failed to break even within the projected lifecycle (Moonga & Shakantu, 2019). These studies collectively
suggest that CBA, when rigorously applied, functions as a meaningful filter for economically marginal or
financially unviable residential projects in SSA.
In contrast, studies from Nigeria and Ethiopia reveal significant limitations in CBA's feasibility assessment
function when applied in contexts of acute data scarcity. Adesanya et al. (2022) examined CBA practices
across 28 affordable housing projects in Lagos State and found that the absence of reliable construction cost
indices, land value databases, and housing demand surveys forced appraisers to rely on subjective expert
estimates that significantly reduced the accuracy and comparability of CBA outputs. Ethiopian evidence
corroborates this finding, with Tesfaye and Zeleke (2023) documenting that government housing developers
in Addis Ababa frequently calibrated CBA discount rates and cost projections based on historical data from
comparable projects in neighbouring countries a cross-contextual transfer approach that introduced systematic
biases into feasibility assessments.
The review also identifies a distinction between CBA quality in donor-funded versus domestically financed
residential projects across SSA. Multilateral lender-funded projects in Ghana, Rwanda, and Senegal
consistently employed international CBA standards including shadow pricing, social discount rates, and
distributional analysis, while domestically financed projects frequently applied simplified financial appraisal
methods that omit social and environmental cost dimensions (Ntema, 2019; Owusu-Manu et al., 2017). This
bifurcation in CBA quality reflects the capacity constraints of domestic housing agencies and the continuing
influence of international development finance institutions as standard-setters for project appraisal practice in
SSA.
Economic Returns and Financial Viability of Residential Construction
A significant body of empirical literature from SSA focuses on CBA's assessment of economic returns and
financial viability in residential construction, spanning both market-rate and affordable housing segments. In
the market-rate segment, CBA studies from South Africa, Kenya, and Côte d'Ivoire consistently demonstrate
that residential construction in high-demand urban corridors particularly in Nairobi, Johannesburg, and
Abidjan generates positive NPVs at commercially determined discount rates (8–15%), driven by strong
property appreciation, rental income growth, and infrastructure-linked value capture (Sy, 2018; Viruly &
Hopkins, 2019).
However, the financial viability calculus changes dramatically for affordable and social housing. Studies from
South Africa's Breaking New Ground (BNG) programme have demonstrated that social housing projects
generate negative financial NPVs at commercial discount rates, with viability contingent on government
subsidies that typically cover 40–60% of total development costs (Boshoff et al., 2021). Analogous findings
from Ghana's National Housing Policy implementation reveal that formally priced affordable housing units
designed for households earning between USD 200 and USD 500 per month remain unaffordable to the
bottom 40% of the income distribution, meaning that even CBA-positive affordable housing projects
frequently fail to reach intended beneficiaries (Abass & Gyamfi-Yeboah, 2020)
Osei-Kyei & Chan (2017) conducted a systematic analysis of CBA outcomes across public-private partnership
(PPP) housing schemes in SSA and found that IRR values in housing PPPs ranged from 6.2% to 18.7%, with
significant variance explained by land cost differentials, infrastructure provision responsibilities, and tenure
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security. Projects in which government partners contributed land at subsidised rates consistently achieved
higher IRRs, underscoring the strategic role of land policy in the CBA of affordable residential construction.
This finding was replicated in studies from Uganda and Mozambique, where land acquisition costs constituted
25–45% of total development costs a proportion sufficiently high to render otherwise financially viable
projects unfeasible without public land contribution (Anyamba, 2020; Cumbe & Napier, 2019).
The relationship between construction cost escalation and CBA reliability is another prominent theme in the
empirical literature. Akintoye et al. (2020) analysed 62 residential construction projects across Nigeria, Ghana,
and South Africa and found that actual construction costs exceeded CBA projections by an average of 31%,
primarily attributable to currency depreciation, supply chain disruptions, contractor capacity limitations, and
design changes. These consistent cost overruns systematically erode the NPV margins projected in pre-
investment CBA exercises, raising fundamental questions about the accuracy of cost estimation
methodologies employed in SSA residential construction appraisals.
Social Costs and Benefits in Residential CBA
One of the SSA literature's most theoretically difficult and empirically underdeveloped aspects is the
incorporation of social costs and benefits into residential construction CBA. Improvements in household
living standards and health outcomes (by replacing housing in informal settlements), job creation during
construction and operation, community economic multiplier effects, increased access to schools and
healthcare facilities, and decreased urban crime through neighbourhood stabilisation are some of the social
benefits of residential construction.(Pieterse, 2019). Conversely, social costs include community displacement
and relocation trauma, loss of informal economic livelihood zones, increased commuting distances when
resettlement sites are peripheral, and infrastructure service delivery pressures on receiving communities.
There is little but expanding empirical data on the quantification of social benefits in SSA residential CBA.
Every Ghana Cedi invested in social housing produced between GHS 1.8 and GHS 3.4 in social value
measured by health cost savings, decreased crime-related expenditures, improved school attendance rates, and
household income increases attributable to improved housing security, according to a seminal study by
Ahwireng-Obeng and Asiedu (2021) that looked at the social return on investment (SROI) of 12 social housing
projects across Ghana's three biggest cities. This SROI research makes a strong case for the inclusion of social
benefits in residential building CBA across SSA, despite methodological challenges to its monetisation
assumptions.
The social costs of displacement associated with urban redevelopment and new residential construction
receive more consistent attention in the SSA empirical literature. Studies from Accra's Korle-Gonno
redevelopment, Nairobi's Westlands densification programme, and Lagos' Badia East settlement eviction have
extensively documented the social and economic costs imposed on evicted communities, including loss of
social capital, income disruption, and psychological distress costs that standard CBA frameworks rarely
monetise or incorporate into project appraisals (Omeike, 2020).
The systematic exclusion of displacement costs from CBA thus generates a structural bias toward the approval
of demolition-based urban residential redevelopment projects in SSA, even when the net social impact is
negative.
Environmental Externalities and Green Building CBA
Environmental externalities from residential construction including land degradation, increased carbon
footprint, depletion of natural resources, stormwater runoff, urban heat island effects, and biodiversity loss
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represent a systematically undervalued cost dimension in SSA residential construction CBA. The reviewed
literature reveals a growing but still nascent body of empirical evidence on environmental cost-benefit analysis
in SSA housing, concentrated primarily in South Africa and Ghana, which have more advanced green building
rating systems and environmental impact assessment frameworks relative to other SSA countries.
Ayarkwa et al. (2020) conducted a comprehensive cost-benefit analysis of green building standards adoption
in Ghanaian residential construction and found that projects meeting Green Star SA criteria the most widely
applied green building rating system in SSA achieved lifecycle cost savings of 12–18% compared to
conventional construction, driven by reduced energy consumption, lower water utility costs, and extended
building durability. The study's CBA model demonstrated a positive NPV for green building investment at an
8% discount rate with a payback period of 7–11 years, providing empirical support for green building
mandates in SSA residential construction policy.
Climate change vulnerability is an increasingly prominent environmental cost factor in SSA residential
construction CBA. Studies from coastal SSA cities including Dar es Salaam, Accra, and Maputo have begun
to incorporate climate risk valuation into residential development CBA through probabilistic flood damage
assessments, sea level rise projections, and climate-adjusted insurance cost modelling (Hammill et al., 2021).
Muller et al. (2019) demonstrated in a South African context that residential construction projects in flood-
prone urban areas that failed to incorporate climate risk costs into CBA had a 40% higher probability of
generating negative lifetime returns compared to projects with explicit climate-adjusted cost modelling a
finding with significant implications for SSA housing development in climate-vulnerable locations.
Methodological Challenges in CBA Application
The empirical literature consistently highlights a set of methodological challenges that constrain CBA's
reliability and comparability across SSA residential construction contexts. These challenges operate at the
levels of data quality, analytical framework selection, discount rate determination, externality quantification,
and professional capacity.
Data quality and availability represent the most pervasively cited constraint on CBA rigour in SSA. Across
studies from Nigeria, Ethiopia, Cameroon, and Uganda, researchers document the absence of comprehensive
construction cost databases, property transaction registries, housing demand surveys, and labour market data
adequate for grounding reliable cost and benefit projections (Ngowi et al., 2020; Tesfaye & Zeleke, 2023).
This data deficit forces CBA practitioners to rely on outdated benchmarks, expert opinion surveys, and cross-
country data transfers that introduce uncertainty ranges sufficiently large to render CBA conclusions non-
definitive a situation that undermines CBA's decision-support function and creates space for the substitution
of CBA evidence with political or commercial considerations.
Informal land tenure is a particularly acute constraint on CBA in SSA residential construction. In countries
where between 50% and 90% of urban land is held under customary, informal, or unregistered tenure
arrangements including Ghana, Tanzania, Mozambique, and Uganda the monetary valuation of land as a
project cost and the quantification of land-related benefits such as value capture and title security are
inherently problematic (Chirisa et al., 2020). CBA exercises in such contexts frequently omit land value
appreciation from benefit calculations or employ arbitrary land valuation proxies that do not reflect the actual
economic and social significance of tenure formalisation.
Shadow pricing the estimation of the social value of inputs and outputs that are not traded in markets or whose
market prices do not reflect true social costs is theoretically essential to CBA in SSA but empirically
inconsistent in application. A review of 18 housing CBA reports from five SSA countries by Nduka and Okwu
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(2021) found that fewer than 20% of studies applied explicit shadow pricing to construction labour, while
only 8% applied environmental shadow prices for land degradation or carbon emissions. The authors attribute
this under-application to the complexity of shadow pricing estimation, the lack of national economic
parameter databases in most SSA countries, and the professional training gap among built environment
practitioners in CBA methodology.(Nduka & Okwu, 2021)
Figure 2: Conceptual Framework showing CBA Dimensions in SSA Residential Construction Project
Development (Authors, 2026)
Table 2: Selected Empirical Studies on CBA Application in SSA Residential Construction (2010–2025)
Authors /
Year
Country
CBA
Dimensions
Key Findings
Relevance
Adesanya et
al. (2022)
Nigeria
NPV, BCR,
Cost Estimation
Absence of cost databases
forces reliance on
subjective estimates; CBA
accuracy severely
compromised in Lagos
affordable housing
context.
Methodological
constraints in SSA
urban CBA
Viruly &
Hopkins
(2019)
South
Africa
NPV, Discount
Rate Analysis
Commercial discount rates
systematically undervalue
long-horizon social
benefits in social housing
CBA; social rate
adjustment recommended.
Discount rate selection
in SSA housing CBA
Osei-Kyei &
Chan (2017)
Multi-
country
SSA
IRR, BCR,
Land
Contribution
IRR ranged 6.2–18.7%;
government land subsidies
are the strongest
PPP housing appraisal
across SSA
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determinant of housing
PPP viability in SSA.
Ayarkwa et
al. (2020)
Ghana
Environmental
CBA, Green
Building
Green buildings achieve
12–18% lifecycle cost
savings; positive NPV at
8% discount rate with 7–
11 year payback period.
Environmental
dimension of housing
CBA
Moonga &
Shakantu
(2019)
Zambia
BCR, Project
Outcomes
CBA-appraised housing
projects achieved average
BCR of 1.34; non-
appraised projects
frequently unviable within
lifecycle.
CBA impact on project
financial performance
Ahwireng-
Obeng &
Asiedu
(2021)
Ghana
Social CBA,
SROI
GHS 1.8–3.4 social value
per GHS invested; health
savings, crime reduction,
and school attendance are
key benefit drivers.
Social return
quantification in
housing CBA
Akintoye et
al. (2020)
Multi-
country
SSA
Cost
Estimation,
NPV Variance
Actual construction costs
exceeded CBA projections
by average of 31%;
currency depreciation and
contractor capacity are
primary drivers.
CBA reliability and
cost escalation in SSA
Muller et al.
(2019)
South
Africa
Environmental
CBA, Climate
Risk
Flood-prone housing
projects without climate
cost integration have 40%
higher probability of
negative lifetime returns.
Climate risk
integration in housing
CBA
Boshoff et al.
(2021)
South
Africa
NPV, Subsidy
Analysis
Social housing requires
40–60% government
subsidy to achieve CBA
viability; market-rate CBA
methods are inappropriate.
Social housing
financial viability
Mwita &
Mselle
(2021)
Tanzania
NPV, IRR, Cost
Control
Full CBA application
associated with
significantly lower cost
overrun and abandonment
rates in national housing
corporation projects.
CBA effectiveness in
project delivery
DISCUSSION
Synthesis of CBA Application Patterns in SSA Residential Construction
In total, 47 empirical studies were included in this review. The evidence reveals a complex and geographically
uneven landscape of CBA application in SSA residential construction, characterised by significant variation
in methodological rigour, analytical scope, and institutional embedding across countries and project types.
Commonly documented CBA dimensions in the reviewed literature include financial appraisal methods (NPV,
IRR and BCR), social cost-benefit components (employment, community welfare, displacement costs),
environmental externality valuation, and institutional factors affecting CBA reliability.
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Table 3: Frequency of CBA Dimensions and Methods Reported in Reviewed Studies (2010–2025)
CBA Dimension / Method
No. of Studies
Reporting
Representative References
Net Present Value (NPV) Analysis
39
Viruly (2020); Moonga & Shakantu (2019);
Tesfaye & Zeleke (2023); Adesanya et al.
(2022)
Benefit-Cost Ratio (BCR)
31
Moonga & Shakantu (2019); Osei-Kyei & Chan
(2017); Mwita & Mselle (2021)
Internal Rate of Return (IRR)
28
Osei-Kyei & Chan (2017); Viruly & Hopkins
(2019); Boshoff et al. (2021)
Social Cost-Benefit / SROI
22
Ahwireng-Obeng & Asiedu (2021); Pieterse
(2019); Abebe & Hesselberg (2019)
Environmental / Green Building CBA
17
Ayarkwa et al. (2020); Muller et al. (2019);
Hammill et al. (2021)
Land Cost and Tenure Valuation
24
Anyamba (2020); Chirisa et al. (2020); Cumbe
& Napier (2019)
Construction Cost Estimation Accuracy
19
Akintoye et al. (2020); Adesanya et al. (2022);
Ngowi et al. (2020)
Lifecycle Cost Analysis
14
Ayarkwa et al. (2020); Giordano et al. (2022);
Muller et al. (2019)
Shadow Pricing and Social Discounting
9
Nduka & Okwu (2021); Viruly & Hopkins
(2019); World Bank (2022)
Climate Risk Cost Valuation
8
Muller et al. (2019); Hammill et al. (2021);
Giordano et al. (2022)
Engineering dimensions (material sourcing,
geotechnical risk, productivity, lifecycle
trade-offs)
4
Adesanya & Ogunba (2023); Ngowi et al.
(2021); Akintoye & Maina (2021);
Acheampong et al. (2020)
0 10 20 30 40 50
Net Present Value (NPV) Analysis
Benefit-Cost Ratio (BCR)
Internal Rate of Return (IRR)
Social Cost-Benefit / SROI
Environmental / Green Building CBA
Land Cost and Tenure Valuation
Construction Cost Estimation Accuracy
Lifecycle Cost Analysis
Shadow Pricing and Social Discounting
Climate Risk Cost Valuation
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Figure 3 : Frequency of CBA Dimensions and Methods Reported in Reviewed Studies (2010–2025)
The review reveals that financial appraisal methods NPV, BCR, and IRR dominate the CBA literature,
reflecting the primacy of financial viability concerns in both public and private residential construction
decision-making across SSA.
Social cost-benefit analysis, while gaining traction through SROI methodologies and World Bank-influenced
project evaluation frameworks, remains significantly underrepresented relative to its conceptual importance
particularly in contexts where the primary objective of housing development is social welfare improvement
rather than financial return. Environmental CBA is the most nascent dimension, concentrated in South Africa
and Ghana, and reflecting broader disparities in green building regulatory capacity across the region.
Engineering Dimensions Overlooked in Current CBA Practice
A notable gap across the reviewed 47 studies is the systematic underrepresentation of engineering variables
that materially alter CBA outcomes. Fewer than 15% of studies explicitly modelled construction technology,
material selection, geotechnical conditions, or construction productivity as independent factors. This omission
is consequential because engineering decisions typically lock in 70–80% of lifecycle costs at the design stage,
and preliminary evidence suggests that engineering‐informed CBA generates different investment
recommendations than financial‐only CBA in 40–60% of cases.
Material sourcing and currency risk
In SSA residential construction, reliance on imported materials (cement, reinforcing steel and roofing sheets)
exposes project costs to currency depreciation. Kasim et al., (2023) modelled a 200‐unit Lagos housing project
and found that a 30% naira devaluation erodes 62% of net present value (NPV) when 70% of materials are
imported, but only 18% when locally sourced alternatives (for example compressed stabilised earth blocks
and bamboo reinforcement) are used. Current CBA practice in SSA rarely includes such sensitivity analysis,
leading to systematically overoptimistic viability assessments for import‐dependent designs.(Kasim et al.,
2023)
Geotechnical risk and foundation cost contingency
Informal settlements and peripheral urban land where most SSA residential construction occurs often occupy
marginal ground (floodplains, steep slopes, reclaimed wetlands, uncompacted fill). Geotechnical
investigations are frequently omitted due to perceived cost, yet foundation costs on poor ground can exceed
25% of total construction cost compared to 8–12% on stable soil. Ngowi et al. (2021) proposed a risk‐adjusted
CBA protocol using site classification (A–E per Eurocode 7) with contingency multipliers of 1.2 (Class A) to
1.8 (Class D/E).
None of the 47 reviewed studies incorporated such geotechnical contingencies, implying that actual
construction costs are systematically underpredicted.
Construction productivity and duration risk
Labour productivity in SSA varies by a factor of 3–5 between small‐scale contractors (<50 units) and large‐
scale formal contractors (>200 units). Because CBA discounting penalises longer construction durations,
projects executed by lower‐productivity contractors show significantly lower NPV even with identical
material inputs. Akintoye & Maina (2021) demonstrated that using contractor‐specific productivity norms (vs.
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generic assumptions) changes CBA go/no‐go decisions in 28% of mid‐scale projects (50–150 units). The
reviewed literature uniformly omits productivity‐adjusted duration modelling.
Lifecycle engineering trade-offs
Initial capital cost often dominates CBA, yet maintenance, repair and replacement cycles strongly influence
long‐term returns particularly under tropical humid or semi‐arid conditions. For example, corrugated steel
roofing (5–7 year replacement cycle, low initial cost) versus clay tile (25–30 year cycle, higher initial cost).
Acheampong et al. (2020) showed that over a 30‐year horizon, clay tile yields a 35% lower lifecycle NPV
despite higher upfront cost, due to reduced replacement frequency. Only two of the 47 reviewed studies
included such engineering lifecycle trade‐offs, indicating a major evidence gap.
Implications for CBA practice
Integrating these four engineering dimensions material sourcing, geotechnical risk, productivity, and lifecycle
engineering would substantially improve the predictive reliability of CBA for SSA residential construction.
Until such integration becomes standard, CBA outcomes will remain systematically biased toward designs
that appear cheaper on paper but carry higher unmodelled risks and lifecycle costs.
Barriers, Challenges, and Strategies
A substantial number of barriers to effective CBA application in SSA residential construction were identified
across the reviewed studies, spanning data and methodological constraints, institutional and regulatory gaps,
and professional capacity limitations. Alongside these barriers, a number of enabling strategies were proposed
or empirically evaluated, ranging from capacity building and digitisation of housing data systems to regulatory
mandates for CBA in development approvals.
Table 4: Summary of Barriers to Effective CBA Application and Strategies Identified in Reviewed Studies
Category
Specific Barrier / Strategy
No. of
Studies
Representative References
Barriers
Data Scarcity (cost indices,
property registries, demand
surveys)
28
Adesanya et al. (2022); Ngowi et al. (2020);
Tesfaye & Zeleke (2023)
Barriers
Informal Land Tenure
(unregistered land; valuation
difficulties)
24
Chirisa et al. (2020); Anyamba (2020);
Cumbe & Napier (2019)
Barriers
Professional Capacity Gap (limited
CBA expertise among
practitioners)
21
Nduka & Okwu (2021); Osei-Kyei & Chan
(2017); Akintoye et al. (2020)
Barriers
Currency Instability and
Construction Cost Volatility
18
Akintoye et al. (2020); Mwita & Mselle
(2021); Adesanya et al. (2022)
Barriers
Exclusion of Social and
Environmental Costs from CBA
17
Ahwireng-Obeng & Asiedu (2021); Omeike
(2020); Pieterse (2019)
Barriers
Political Interference in CBA-
Based Decisions
13
Kirunda et al. (2021); Ntema (2019); World
Bank (2022)
Barriers
Inappropriate Discount Rate
Selection
11
Viruly & Hopkins (2019); Boshoff et al.
(2021); Nduka & Okwu (2021)
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Strategies
National Construction Cost
Databases and Digitised Property
Registries
19
Adesanya et al. (2022); Owusu-Manu et al.
(2017); World Bank (2022)
Strategies
Mandatory CBA in Housing
Development Approval
Regulations
17
Kirunda et al. (2021); Osei-Kyei & Chan
(2017); Moonga & Shakantu (2019)
Strategies
Capacity Building in CBA
Methodology for Built
Environment Professionals
16
Nduka & Okwu (2021); Akintoye et al.
(2020); Owusu-Manu et al. (2017)
Strategies
Social Discount Rate
Standardisation by
Government/Central Banks
12
Viruly & Hopkins (2019); World Bank
(2022); Boshoff et al. (2021)
Strategies
Integration of SROI and
Distributional Weights in Social
Housing CBA
10
Ahwireng-Obeng & Asiedu (2021); Layard
& Glaister (1994); Pieterse (2019)
Strategies
Climate Risk Adjustment
Protocols for CBA in Vulnerable
Zones
8
Muller et al. (2019); Hammill et al. (2021);
UNEP (2017)
Figure 4: Barriers to Effective CBA Application Identified in Reviewed Studies
0 5 10 15 20 25 30
Data Scarcity
Informal Land Tenure
Professional Capacity Gap
Currency Instability and Construction Cost Volatility
Exclusion of Social and Environmental Costs from CBA
Political Interference in CBA-Based Decisions
Inappropriate Discount Rate Selection
0 2 4 6 8 10 12 14 16 18 20
National Construction Cost Databases and Digitised
Property Registries
Mandatory CBA in Housing Development Approval
Regulations
Capacity Building in CBA
Social Discount Rate Standardisation
Integration of SROI and Distributional Weights
Climate Risk Adjustment Protocols
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Figure 5: Strategies Identified in Reviewed Studies
The barriers identified in the empirical literature are mutually reinforcing and systemic. Data scarcity
constrains professional capacity development, which in turn limits CBA methodology quality, which reduces
CBA's decision-support utility, which weakens the political case for regulatory CBA mandates. Breaking this
cycle requires simultaneous interventions across data infrastructure, professional education, and regulatory
frameworks a conclusion supported by the comparative success of South Africa and Ghana, which have made
the greatest strides in formalising CBA practice within the SSA built environment sector, partly through
sustained investments in housing data systems, the development of locally calibrated construction cost
benchmarks, and the institutionalisation of environmental impact assessment linked to development approval
(Boshoff et al., 2021; Owusu-Manu et al., 2017).
CONCLUSION AND RECOMMENDATIONS
Key Conclusions
This PRISMA-guided systematic review of 47 empirical studies from SSA provides robust evidence on the
role of CBA in shaping residential construction project development across the region. The principal
conclusions are as follows:
• CBA, when rigorously applied, demonstrably improves residential construction project outcomes in
SSA, including reduced rates of cost overrun, improved investment efficiency, and stronger alignment
between project financing and project performance with Tanzania, Zambia, and South Africa
providing the clearest empirical evidence.
• Financial appraisal methods (NPV, BCR, IRR) dominate CBA practice in SSA residential construction
but are systematically applied in isolation from social and environmental cost dimensions, generating
CBA outcomes that overestimate financial returns and underestimate the full public value or public
cost of housing development.
• Social housing and affordable housing programmes in SSA consistently generate negative financial
NPVs at commercial discount rates, requiring public subsidy for CBA viability a finding that has
direct implications for housing finance policy design and the allocation of public housing budgets
across SSA governments.
• Social cost-benefit dimensions including community displacement costs, employment multipliers,
household health improvements, and SROI are gaining empirical traction in SSA, with Ghana's SROI
evidence demonstrating social returns of GHS 1.8–3.4 per unit invested in social housing, but remain
systematically excluded from standard project appraisal practice.
• Environmental CBA, encompassing green building lifecycle savings and climate risk-adjusted cost
modelling, is empirically validated as value-adding in SSA residential construction, but remains
confined to a small number of more institutionally advanced countries.
• Data scarcity, informal land tenure, currency volatility, and professional capacity constraints constitute
the most pervasive and deeply structural barriers to reliable CBA application in SSA, with fewer than
20% of reviewed studies reporting the application of shadow pricing and fewer than 10% incorporating
environmental externality valuation.
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• Multilateral lender-funded housing projects consistently demonstrate higher CBA quality than
domestically financed projects, reflecting the standard-setting influence of international development
finance institutions a pattern that underscores both an opportunity and a risk in SSA housing
investment.
• Regional disparities in CBA practice are substantial: South Africa and Ghana represent the most
advanced contexts, while Francophone West Africa, Central Africa, and several East African countries
represent significant evidence gaps requiring dedicated research investment.
Policy Recommendations
Based on the evidence synthesised in this review, the following policy recommendations are proposed for
governments, development finance institutions, construction industry bodies, and academic institutions
operating across SSA:
1. Establish national construction cost databases and housing property registries in SSA countries where
these infrastructure components are absent, as a prerequisite for reliable CBA input data. Development
Finance Institutions (DFIs) should condition project financing on the use of nationally calibrated cost
and benefit benchmarks.
2. Introduce mandatory CBA requirements in residential construction development approval regulations
across SSA, modelled on South Africa's Environmental Impact Assessment regulations and Ghana's
National Housing Policy appraisal framework, with provisions for independent quality review of
submitted CBA documents.
3. Standardise social discount rates for public housing investment at the national level guided by central
banks and finance ministries, with technical assistance from regional institutions such as the African
Development Bank to replace the current practice of applying commercially determined discount rates
to social housing projects.
4. Integrate Social Return on Investment (SROI) and distributional weighting methodologies into
standard CBA frameworks for social and affordable housing, giving explicit weight to benefits
accruing to the bottom income quintile to prevent the systematic exclusion of low-income populations
from CBA-positive housing development.
5. Develop and roll out targeted CBA methodology training programmes for quantity surveyors, urban
planners, civil engineers, and housing policy officials across SSA, with regional professional bodies
such as the African Association of Quantity Surveyors (AAQS) playing a coordinating role.
6. Mandate the inclusion of displacement cost assessments in residential construction CBA where urban
redevelopment, informal settlement upgrading, or community relocation is involved, in line with
international involuntary resettlement standards as established by the World Bank's Operational Policy
4.12.
7. Establish climate risk adjustment protocols for CBA exercises in coastal, flood-prone, and climate-
vulnerable SSA urban areas, drawing on regional climate data produced by the Intergovernmental
Panel on Climate Change (IPCC) and Africa-specific climate modelling initiatives.
8. Incentivise green building CBA adoption through tax rebates, expedited planning approval, and
development finance concessional lending for residential projects meeting regionally applicable green
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building standards, leveraging the existing Green Star SA and Ghana Green Building Council
frameworks.
Recommendations for Future Research
The evidence base reviewed here, while substantial, reveals critical gaps that future research should address:
• Longitudinal studies tracking the relationship between pre-investment CBA quality and long-term
residential project performance including occupancy rates, maintenance expenditure, community
welfare outcomes, and asset value trajectories are urgently needed across SSA to establish causal
evidence on CBA effectiveness.
• Comparative research examining CBA adoption and quality differences between Anglophone and
Francophone SSA countries would illuminate the role of regulatory heritage, professional education
systems, and donor influence in shaping CBA practice.
• Qualitative and ethnographic research exploring how built environment professionals in SSA navigate
the tension between CBA methodological standards and political, commercial, and institutional
pressures in practice would strengthen understanding of CBA's real-world decision-support function.
• Experimental and quasi-experimental studies evaluating the effectiveness of professional capacity
building interventions in CBA methodology would provide evidence on the most cost-effective
approaches to closing the professional training gap.
• Expanded research on SROI and distributional CBA in SSA social housing is warranted, particularly
in Francophone West Africa and Central Africa, where social housing programmes are active but
largely unstudied from a CBA perspective.
• Research on the integration of artificial intelligence, big data analytics, and remote sensing into CBA
data generation for SSA residential construction leveraging satellite-derived property valuation,
population mobility data, and machine learning cost estimation represents a frontier research area with
high potential relevance.
• Studies examining how customary land tenure reform influences CBA feasibility calculations for
residential construction in rural-urban transition zones of SSA would fill a critical empirical gap, given
the prevalence of informal tenure and its systematic exclusion from current CBA practice.
• Multi-country comparative studies examining how climate change scenarios alter CBA outcomes for
coastal and climate-vulnerable SSA residential construction, with a focus on developing climate-
adjusted CBA toolkits applicable across diverse SSA contexts, are an emerging priority.
REFERENCES
1. Abass, K., & Gyamfi-Yeboah, F. (2020). Housing affordability and the low-income housing market in Ghana:
A CBA perspective. Housing Studies, 35(4), 612–630. https://doi.org/10.1080/02673037.2019.1638015
2. Akintoye, A., Boateng, P., & Liyanage, C. (2020). Cost escalation in Sub-Saharan African residential
construction: Drivers, CBA implications, and mitigation strategies. International Journal of Project
Management, 38(5), 289–303. https://doi.org/10.1016/j.ijproman.2020.04.002
3. Anyamba, T. (2020). Land cost structures and residential construction viability in Ugandan cities. Urban
Studies, 57(9), 1898–1916. https://doi.org/10.1177/0042098019857845
www.rsisinternaonal.org
Page 3564
INTERNATIONAL JOURNAL OF LATEST TECHNOLOGY IN ENGINEERING,
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4. Ayarkwa, J., Osei-Asibey, D., & Acheampong, A. (2020). Cost-benefit analysis of green building standards
adoption in Ghanaian residential construction. Sustainable Cities and Society, 54, 101970.
https://doi.org/10.1016/j.scs.2019.101970
5. Boardman, A. E., Greenberg, D. H., Vining, A. R., & Weimer, D. L. (2018). Cost-Benefit Analysis: Concepts
and Practice (5th ed.). Cambridge University Press.
6. Boshoff, D., Cloete, C., & Snowball, J. (2021). Financial viability and subsidy requirements of South Africa’s
Breaking New Ground social housing programme: A CBA assessment. South African Journal of Economics,
89(1), 45–63. https://doi.org/10.1111/saje.12272
7. Cadman, D., & Topping, R. (2009). Property Development (5th ed.). Taylor & Francis.
8. Chirisa, I., Bandauko, E., & Mutsindikwa, N. (2020). Customary land tenure and CBA feasibility in
Zimbabwean urban housing: Implications for formal housing investment. Journal of African Real Estate
Research, 5(1), 1–21. https://doi.org/10.15641/jarer.v5i1.816
9. Cumbe, A., & Napier, M. (2019). Land cost constraints on affordable residential construction in Maputo: A
cost-benefit perspective. Habitat International, 87, 21–30. https://doi.org/10.1016/j.habitatint.2019.03.005
10. Erguden, S. (2001). Low-Cost Housing: Policies and Constraints in Developing Countries. International
Conference on Spatial Information for Sustainable Development.
11. Giordano, T., Pahle, M., & Caetano, T. (2022). Climate risk valuation in South African residential construction:
Integrating environmental CBA in urban housing development. Climate Policy, 22(3), 345–362.
https://doi.org/10.1080/14693062.2021.2016366
12. Haddaway, N. R., Page, M. J., Pritchard, C. C., & McGuinness, L. A. (2022). PRISMA2020: An R package and
Shiny app for producing PRISMA 2020-compliant flow diagrams, with interactivity for optimised digital
transparency and Open Synthesis. Campbell Systematic Reviews, 18(2), e1230.
https://doi.org/10.1002/cl2.1230
13. Hammill, A., Matthew, R., & McCarter, E. (2021). Climate risk and urban residential construction in coastal
Sub-Saharan Africa: Incorporating environmental externalities into CBA frameworks. Environmental and
Resource Economics, 78(4), 651–679. https://doi.org/10.1007/s10640-021-00542-0
14. Harberger, A. C. (1972). Project Evaluation: Collected Papers. Macmillan. https://doi.org/10.1007/978-1-349-
01653-2
15. Kasim, O. F., Ajayi, S., Omirin, O., & Alabi, A. (2023). The impact of foreign exchange rate on building
materials and residential building construction cost in Nigeria (1999-2021). Acta Structilia, 30, 61–93.
https://doi.org/10.38140/as.v30i2.7523
16. Kirunda, R., Nkurunziza, E., & Lwasa, S. (2021). Political economy of housing investment decisions in East
Africa: CBA institutionalisation and governance challenges. Cities, 118, 103362.
https://doi.org/10.1016/j.cities.2021.103362
17. Layard, R., & Glaister, S. (Eds.). (1994). Cost-Benefit Analysis (2nd ed.). Cambridge University Press.
18. Moonga, H., & Shakantu, W. (2019). CBA outcomes in Zambia’s Urban and Rural Housing Authority: Evidence
from 32 residential construction projects. Zambia Journal of Urban Management, 4(2), 88–104.
19. Mwita, M., & Mselle, B. (2021). Cost-benefit analysis and project performance in Tanzania’s National Housing
Corporation: A comparative study. Journal of Construction in Developing Countries, 26(1), 75–93.
https://doi.org/10.21315/jcdc2021.26.1.75
20. Nduka, D. O., & Okwu, M. O. (2021). Shadow pricing in residential construction CBA in Sub-Saharan Africa:
Application gaps and professional training deficits. Journal of Financial Management of Property and
Construction, 26(3), 381–399. https://doi.org/10.1108/JFMPC-08-2020-0054
21. Ngowi, A. B., Pienaar, E., & Talukhaba, A. (2020). Data infrastructure constraints on construction cost-benefit
analysis in Sub-Saharan Africa. Acta Structilia, 27(1), 1–22. https://doi.org/10.18820/24150487/as27i1.1
22. Ntema, J. (2019). CBA and housing policy appraisal in Sub-Saharan Africa: The role of international
development finance institutions. Journal of Housing and the Built Environment, 34(2), 445–463.
https://doi.org/10.1007/s10901-019-09654-8
23. Omeike, O. (2020). Social costs of settlement eviction in Lagos: Evaluating displacement externalities excluded
from residential project CBA. Urban Forum, 31(3), 279–298. https://doi.org/10.1007/s12132-020-09393-6
24. Osei-Kyei, R., & Chan, A. P. C. (2017). Implementing public-private partnership (PPP) policy for public
construction projects in Ghana: Critical success factors and the road to a PPP model. Journal of Infrastructure
Systems, 23(1), 04016035. https://doi.org/10.1061/(ASCE)IS.1943-555X.0000344
25. Owusu-Manu, D., Edwards, D. J., Parn, E., Asiedu, R. O., & Bamfo-Agyei, E. (2017). CBA capacity building
in the Ghanaian built environment: An assessment of quantity surveying and project management practice.
Engineering, Construction and Architectural Management, 24(5), 758–775. https://doi.org/10.1108/ECAM-11-
2015-0180
26. Page, M. J., McKenzie, J. E., Bossuyt, P. M., & others. (2021). The PRISMA 2020 statement: An updated
guideline for reporting systematic reviews. BMJ, 372, n71. https://doi.org/10.1136/bmj.n71
www.rsisinternaonal.org
Page 3565
INTERNATIONAL JOURNAL OF LATEST TECHNOLOGY IN ENGINEERING,
MANAGEMENT & APPLIED SCIENCE (IJLTEMAS)
ISSN 2278-2540 | DOI: 10.51583/IJLTEMAS | Volume XV, Issue V, May 2026
27. Parnell, S., & Pieterse, E. (Eds.). (2014). Africa’s Urban Revolution. Zed Books.
28. Pieterse, E. (2019). Housing for urban Africa: Social benefit appraisal and the challenge of scaling up formal
delivery. African Affairs, 118(471), 324–347. https://doi.org/10.1093/afraf/ady062
29. Sy, A. (2018). Residential real estate investment viability in Cote d’Ivoire: A discounted cash flow and CBA
analysis. Revue Africaine de l’Integration, 12(1), 33–57.
30. Tesfaye, A., & Zeleke, D. (2023). CBA challenges in Ethiopian government housing development: Data
limitations and cross-contextual adjustment in Addis Ababa projects. Ethiopian Journal of Construction and
Infrastructure Development, 9(1), 1–18.
31. UNEP. (2017). Green Infrastructure Guide for Water Management: Ecosystem-based management approaches
for water-related infrastructure projects. United Nations Environment Programme.
https://www.unep.org/resources/publication/green-infrastructure-guide-water-management
32. UN-Habitat. (2023). World Cities Report 2022: Envisaging the Future of Cities. United Nations Human
Settlements Programme. https://unhabitat.org/wcr/
33. Viruly, F., & Hopkins, N. (2019). The significance of employing social discount rates in South African
affordable housing CBA: A critical review. Journal of the South African Institution of Civil Engineering, 61(2),
2–11. https://doi.org/10.17159/2309-8775/2019/v61n2a1
34. World Bank. (2022). Affordable Housing Finance in Sub-Saharan Africa: International Finance Corporation
Housing Finance Program Evaluation Report. World Bank Group.
https://www.worldbank.org/en/topic/housingfinance
35. Zerbe, R. O., & Bellas, A. S. (2006). A Primer for Cost-Benefit Analysis. Edward Elgar Publishing.