Application of Non‑Degradable Waste as Building Material for Low‑Cost Housing
Introduction
Application of Non‑Degradable Waste represents a transformative approach to addressing two interconnected global challenges: the urgent need for affordable housing and the escalating crisis of municipal solid waste management.
This comprehensive summary analyzes a pivotal 2023 scientific study published in Scientific Reports, which investigates the feasibility of repurposing disposable diaper waste as a composite building material within Indonesia's regulatory framework.
The research demonstrates that strategic integration of non-degradable waste into construction workflows can simultaneously reduce environmental burden and lower material costs for low-cost housing projects.
Understanding the Dual Crisis: Housing Shortages and Waste Accumulation
Low-cost housing, defined as dwellings that maintain appropriate quality and location without compromising occupants' ability to meet other essential living costs, remains critically undersupplied across developing nations.
In Indonesia specifically, urban populations grow at 4.1% annually, with projections indicating 68% of citizens will reside in urban areas by 2025.
This demographic shift intensifies pressure on housing markets: annual demand reaches 780,000 units while stakeholder delivery capacity remains limited to 400,000–500,000 units, creating a persistent backlog of approximately 300,000 homes yearly.
Concurrently, waste management presents a parallel challenge. National statistics document total waste generation rising from 29.21 million tons in 2019 to 32.76 million tons in 2020.
Within this stream, disposable diaper consumption has increased alongside population growth and changing childcare practices since their commercial introduction in the 1960s.
The application of non‑degradable waste as a construction resource directly addresses both systemic pressures by converting environmental liability into a structural asset.
Methodology: Experimental Design and Regulatory Compliance
The research employed laboratory-based experimental procedures to evaluate composite materials incorporating processed disposable diaper waste. Two distinct material categories were tested: concrete composites intended for structural elements (columns, beams) and mortar composites designed for architectural components (non-bearing walls, floors).
All formulations adhered to Indonesian National Standards (Standard Nasional Indonesia/SNI), including SNI 2847:2019 for structural concrete requirements and SNI 03-6882-2002 for mortar specifications.
Critical to the methodology was accounting for material density differentials when substituting fine aggregates with lightweight diaper polymers. Researchers developed calculation formulas incorporating waste density (ρw), fine aggregate density (ρfa), and replacement percentage (%rep) to determine precise mass equivalents.
Prepared samples—cubes (15×15×15 cm) and cylinders for concrete, 5×5×5 cm blocks for mortar—underwent 28-day curing periods before compressive strength testing.
Application of Non‑Degradable Waste: Experimental Results and Strength Analysis
Experimental findings revealed clear inverse relationships between diaper waste substitution rates and compressive strength. Normal concrete achieved 24.91 MPa, closely matching the target design strength of 25 MPa.
However, as disposable diaper content increased, structural capacity declined predictably. Linear regression analysis produced predictive equations for strength estimation:
- Concrete: y = −56.681x + 26.191
- Mortar: y = −20.57x + 10.364
Where y represents compressive strength (MPa) and x denotes the percentage substitution of fine aggregate by disposable diaper material.
These equations enable practitioners to forecast material performance based on intended waste incorporation levels. Results indicated that structural components requiring higher strength thresholds (20–25 MPa) accommodate maximum substitution rates of 10%, suitable for buildings up to three stories.
For single-story housing applications where 10 MPa suffices, substitution may reach 27%. Non-structural architectural elements permit higher incorporation: concrete bricks allow up to 40% replacement for Level IV classification (non-load-bearing, plastered partitions), while paving blocks accommodate 9% substitution for Level D applications (residential flooring, garden pathways).
Practical Implementation: Material Quantities for Prototype Housing
Translating experimental data into actionable design guidance, researchers modeled a 36 m² low-cost housing unit compliant with Indonesian standards for four-person households.
Comprehensive material quantification revealed that constructing this prototype requires 22.79 m³ of total composite material, of which 1.73 m³ comprises processed disposable diaper waste. This represents an aggregate fine aggregate substitution rate of 7.6% across all building components.
Component-specific breakdown demonstrates strategic allocation: structural columns and beams utilize concrete with 27% diaper content (10.35 MPa strength), wall assemblies employ mortar with 40% substitution (2.14 MPa), and flooring systems incorporate mortar with 9% replacement (8.51 MPa).
This tiered approach optimizes waste utilization while maintaining compliance with performance requirements for each structural role.
Broader Implications for Sustainable Construction Policy
The application of non‑degradable waste in housing construction carries significant policy implications.
Current building regulations in many developing contexts remain anchored to conventional materials and techniques, often reflecting colonial-era standards or imported specifications that limit the adoption of locally appropriate, cost-effective alternatives.
Evidence demonstrating that diaper-recycled composites can meet established strength thresholds provides an empirical foundation for regulatory modernization.
Furthermore, life-cycle assessments referenced in the study indicate that recycling disposable diapers as concrete components yields superior environmental outcomes compared to incineration or co-firing alternatives, particularly regarding carbon emissions and eco-cost metrics.
The relatively low technological barriers to implementation—requiring only washing, drying, shredding, and standard mixing procedures—enhance accessibility for community-scale production in resource-constrained settings.
Implementation Challenges and Future Research Directions
Despite promising results, scaling the application of non‑degradable waste faces practical hurdles. Effective diaper recycling necessitates coordinated waste collection, sanitization protocols (sodium chloride treatment shows promise), and mechanical shredding infrastructure—capabilities currently concentrated in developed economies.
Stakeholder engagement across municipal authorities, waste management enterprises, and construction firms remains essential for establishing viable supply chains.
Additional research priorities include comprehensive structural analysis incorporating soil-bearing capacity and dynamic load assessments, detailed cost-benefit evaluations comparing recycled-composite versus conventional material procurement, and exploration of financial mechanisms to integrate these materials into affordable housing subsidy programs.
The study's authors note that patent processes currently restrict public dataset availability, though reasonable requests to corresponding authors may facilitate academic collaboration.
Conclusion: Reinforcing the Document's Ongoing Value
This scientific investigation provides robust, standards-aligned evidence that the application of non‑degradable waste as building material offers a technically feasible pathway toward more sustainable, affordable housing solutions.
By establishing clear substitution thresholds, predictive strength models, and prototype-scale material quantifications, the research equips policymakers, practitioners, and researchers with actionable intelligence for advancing circular economy principles in construction.
As urbanization pressures and waste management challenges intensify globally, the methodological rigor and practical orientation of this work ensure its continued relevance for professionals committed to dignified, ecologically responsible housing development.
The application of non‑degradable waste thus emerges not merely as a technical innovation, but as a strategic framework for reconciling social equity, environmental stewardship, and economic viability in the built environment.