AN ASSESSMENT OF SUSTAINABLE HOUSING AFFORDABILITY USING A MULTIPLE CRITERIA DECISION-MAKING METHOD

Introduction

An assessment of sustainable housing affordability has become increasingly vital in the face of growing urban populations, climate change, and economic inequality. As cities expand and housing costs rise, the need to balance environmental responsibility with financial accessibility has never been more urgent. Traditional definitions of housing affordability—often limited to income-to-rent ratios—fail to capture the full picture, especially when long-term costs like energy, water, maintenance, and transportation are ignored.

To address this complexity, researchers and policymakers have turned to advanced analytical tools, particularly Multiple Criteria Decision Making (MCDM) methods, to conduct a more holistic assessment of sustainable housing affordability. This summary explores how MCDM frameworks enhance our understanding of housing sustainability and affordability, enabling more informed, equitable, and resilient urban development decisions.

Understanding Sustainable Housing Affordability

An assessment of sustainable housing affordability goes beyond the simple question of whether a household can pay rent or mortgage. It incorporates environmental, economic, social, and technical dimensions to evaluate whether a home is not only financially accessible but also resource-efficient, healthy, durable, and located in a supportive community. For instance, a low-income family might afford a home on the urban fringe, but if it leads to high transportation costs, poor access to services, and inefficient energy use, true affordability is compromised. An assessment of sustainable housing affordability thus considers a broader set of criteria, including:

• Initial purchase or rental cost
• Energy and water efficiency
• Maintenance and lifecycle costs
• Indoor air quality and health impacts
• Proximity to jobs, schools, and public transit
• Resilience to climate risks
• Use of sustainable building materials
• Social inclusivity and accessibility

By integrating these factors, an assessment of sustainable housing affordability provides a more accurate and forward-looking picture of housing value. This comprehensive approach is essential for guiding policy, investment, and planning in ways that promote long-term well-being for individuals and communities.

Introduction to Multiple Criteria Decision Making (MCDM)

An assessment of sustainable housing affordability benefits greatly from the application of Multiple Criteria Decision Making (MCDM) methods. MCDM is a structured decision-support framework used when multiple, often conflicting, criteria must be evaluated simultaneously. In the context of housing, trade-offs are common: a home may be affordable but located in a flood-prone area, or highly energy-efficient but out of reach for low-income families. MCDM helps decision-makers weigh these factors objectively and transparently. Common MCDM techniques include:

• Analytic Hierarchy Process (AHP): Allows decision-makers to assign weights to different criteria based on pairwise comparisons.
• Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS): Ranks alternatives by measuring their distance from an ideal and anti-ideal solution.
• Elimination and Choice Expressing Reality (ELECTRE): Uses outranking methods to eliminate inferior options.
• VIKOR (VlseKriterijumska Optimizacija I Kompromisno Resenje): Focuses on compromise solutions that are closest to the ideal.

An assessment of sustainable housing affordability using MCDM typically follows a structured process: defining objectives, identifying alternatives (e.g., housing types or locations), selecting criteria, assigning weights, scoring options, and ranking outcomes. This method brings clarity to complex decisions and supports evidence-based policy.

Application of MCDM in Housing Studies

An assessment of sustainable housing affordability using MCDM has been applied in numerous academic and policy contexts. For example, researchers in Europe have used AHP to compare social housing projects based on energy performance, construction cost, and resident satisfaction. In one study, public housing units retrofitted with solar panels and insulation scored higher on sustainability but required higher upfront investment. MCDM allowed policymakers to justify the long-term savings and environmental benefits, supporting funding decisions. In developing countries, an assessment of sustainable housing affordability using MCDM has helped prioritize low-cost housing designs that balance affordability with climate resilience. In India, for instance, TOPSIS was used to evaluate different building materials—such as compressed earth blocks, bamboo, and recycled concrete—based on cost, thermal performance, durability, and carbon footprint. The results guided local governments in selecting materials that were both affordable and sustainable, especially in rural and peri-urban areas. Another example comes from South Africa, where VIKOR was applied to assess informal settlement upgrading projects. Criteria included relocation distance, access to services, construction speed, and community participation. An assessment of sustainable housing affordability in this context revealed that solutions perceived as “cheapest” often failed on social and environmental grounds, leading to more balanced and inclusive redevelopment plans. These applications demonstrate that an assessment of sustainable housing affordability using MCDM is not just theoretical—it produces actionable insights that improve real-world outcomes.

Key Criteria in Sustainable Housing Evaluation

An assessment of sustainable housing affordability relies on a well-defined set of criteria, each reflecting a critical dimension of housing performance. These criteria are typically grouped into three main categories: economic, environmental, and socio spatial.

1. Economic Criteria:
   • Initial construction or purchase cost
   • Monthly utility bills (electricity, water, heating)
   • Maintenance and repair expenses
   • Financing options and subsidies
   • Long-term cost of ownership
2. Environmental Criteria:
   • Energy efficiency (e.g., insulation, passive solar design)
   • Water conservation (rainwater harvesting, low-flow fixtures)
   • Use of renewable energy (solar, wind)
   • Carbon footprint of materials and construction
   • Waste management and recyclability
3. Socio-Spatial Criteria:
   • Proximity to employment and education
   • Access to healthcare and public services
   • Safety and crime rates
   • Walkability and public transit access
   • Community cohesion and cultural fit

An assessment of sustainable housing affordability assigns weights to these criteria based on stakeholder priorities—such as government agencies, developers, or residents. For example, a city focused on decarbonization might assign higher weight to energy efficiency, while a low-income housing program might prioritize initial cost and transportation access.

Stakeholder Involvement and Weighting

A critical strength of an assessment of sustainable housing affordability using MCDM is its ability to incorporate diverse stakeholder perspectives. Unlike top-down models, MCDM allows for participatory decision-making, where input from residents, planners, engineers, and financiers shapes the evaluation process. For instance, in a study conducted in Canada, AHP was used to gather preferences from low-income households, housing providers, and municipal officials. While officials emphasized energy efficiency and building codes, residents prioritized proximity to family, safety, and natural light. An assessment of sustainable housing affordability that integrates such varied viewpoints leads to more equitable and accepted outcomes. The weighting process in MCDM ensures that no single criterion dominates unless justified. For example, if transportation cost is weighted heavily due to high fuel prices, housing located near transit hubs will rank higher—even if slightly more expensive to rent. This reflects the real-life trade-offs families make daily.

Case Study: Comparing Housing Models in a European City

An assessment of sustainable housing affordability was conducted in a mid-sized European city to compare four housing models:

1. Conventional social housing
2. Passive house-certified affordable units
3. Modular prefabricated homes
4. Community land trust (CLT) developments

Using TOPSIS, researchers evaluated each model across 12 criteria, including construction cost, energy use, indoor air quality, and resident satisfaction. Data was collected from building audits, utility records, and resident surveys. The results showed that while conventional social housing had the lowest upfront cost, it performed poorly on energy efficiency and long-term maintenance. In contrast, passive house units had higher initial costs but significantly lower utility bills and better indoor comfort, making them more sustainable over time. Modular homes offered fast construction and flexibility but varied in quality. CLT developments scored highest on social sustainability and long-term affordability due to land ownership models. An assessment of sustainable housing affordability using MCDM clearly demonstrated that the most “affordable” option depends on the time frame and criteria emphasized. For long-term resilience and resident well-being, investments in higher-performance housing were justified.

Advantages of MCDM in Policy and Planning

An assessment of sustainable housing affordability using MCDM offers several advantages for local governments and planners:

• Transparency: The decision process is documented and open to scrutiny, reducing bias and corruption.
• Flexibility: Criteria and weights can be adjusted based on local priorities or changing conditions.
• Comparability: Different housing projects or policies can be objectively compared.
• Stakeholder Buy-In: Involving communities in weighting criteria increases trust and adoption.
• Scenario Testing: Policymakers can simulate how changes—like rising energy prices or new subsidies—affect outcomes.

For example, a city planning to build 1,000 new affordable homes can use MCDM to test whether investing in solar panels or better insulation delivers greater long-term savings. An assessment of sustainable housing affordability in such cases supports smarter budget allocation and stronger public justification.

Challenges and Limitations

Despite its strengths, an assessment of sustainable housing affordability using MCDM is not without challenges. One major issue is data availability. Reliable information on energy use, maintenance costs, or resident satisfaction may be scarce, especially in informal or low-income housing sectors. Poor data quality can undermine the accuracy of MCDM results. Another challenge is subjectivity in weighting. While MCDM structures decision-making, the assignment of weights still depends on human judgment. Different stakeholders may assign vastly different importance to criteria, leading to conflicting outcomes. Sensitivity analysis—testing how results change with different weights—can help address this, but it adds complexity. Additionally, MCDM models can become overly technical, alienating non-expert stakeholders. If not communicated clearly, the results may be misunderstood or ignored by policymakers or communities. Therefore, visualizations, summaries, and participatory workshops are essential to bridge the gap between analysis and action.

Integration with Urban Planning and Smart Cities

An assessment of sustainable housing affordability is increasingly being integrated into broader urban planning and smart city initiatives. With the rise of digital twins, geographic information systems (GIS), and real-time data monitoring, MCDM models can now be linked to live urban datasets. For instance, a city might use GIS to map housing options alongside transportation networks, flood zones, and heat islands. This spatial data can feed into an assessment of sustainable housing affordability, allowing planners to identify optimal locations for new developments. Smart meters and IoT sensors can provide real-time energy and water usage data, improving the accuracy of sustainability scores. In smart city frameworks, an assessment of sustainable housing affordability can be automated and updated regularly, supporting dynamic policy adjustments. For example, if energy prices spike, the system could re-rank housing options to reflect new cost realities, guiding subsidy programs accordingly.

Future Directions and Innovations

The future of an assessment of sustainable housing affordability using MCDM lies in greater integration, automation, and inclusivity. Emerging technologies like artificial intelligence and machine learning can enhance MCDM by identifying patterns in large datasets and predicting long-term performance of housing models. Blockchain technology could ensure transparency in data collection and funding allocation, especially in public housing projects. Virtual reality (VR) tools could allow residents to “experience” different housing options before decisions are made, improving engagement. Moreover, global initiatives like the UN’s Sustainable Development Goals (SDG 11: Sustainable Cities and Communities) are encouraging cities to adopt standardized metrics for housing sustainability. An assessment of sustainable housing affordability using MCDM can align with these frameworks, enabling cross-city comparisons and benchmarking.

Conclusion

An assessment of sustainable housing affordability using a Multiple Criteria Decision-Making method represents a powerful shift from narrow, short-term thinking to holistic, long-term planning. By considering economic, environmental, and social factors together, this approach reveals the true cost and value of housing options. An assessment of sustainable housing affordability is not just about numbers—it’s about people, communities, and the planet. For local governments, national agencies, and international organizations, adopting MCDM-based assessments can lead to more equitable, resilient, and sustainable housing policies. As urbanization accelerates and climate pressures mount, the need for intelligent, data-driven decisions has never been greater. An assessment of sustainable housing affordability is not a luxury—it is a necessity for building cities that are truly livable for all. Through continued research, stakeholder engagement, and technological innovation, an assessment of sustainable housing affordability will remain a cornerstone of 21st-century urban development. Whether evaluating a single home or an entire city’s housing stock, MCDM provides the clarity and rigor needed to make choices that balance affordability with sustainability—today and for generations to come. Also read: Structural Equation Modelling of Users' Assessment of Affordable Housing in Developing Cities