Selective Deconstruction Slashes Housing Environmental Footprint by 70%

Why It Matters

This research highlights a critical, yet often overlooked, aspect of the building lifecycle: the environmental impact of materials. By shifting from a linear 'take-make-dispose' model to a circular approach, designers and engineers can significantly mitigate the substantial carbon footprint associated with construction and demolition waste.

Key Finding

The study found that carefully dismantling buildings for material reuse and recycling (selective deconstruction) is far more environmentally beneficial than simply demolishing and landfilling them, leading to substantial reductions in emissions, water use, and resource depletion.

Key Findings

• Selective deconstruction can reduce greenhouse gas emissions by 70% in Lima compared to landfilling.
• Selective deconstruction can reduce water consumption by 67% in Lima compared to landfilling.
• Selective deconstruction can reduce fossil resource usage by 69% in Lima compared to landfilling.
• Circular strategies offer significant environmental benefits across different global contexts.

Research Evidence

Aim: What is the potential of circular strategies, specifically selective deconstruction, to reduce the environmental impact (energy, water, GHG emissions) of housing in the Global North and Global South?

Method: Life Cycle Assessment (LCA)

Procedure: A life cycle assessment was conducted on housing stocks in Montreal (Canada) and Lima (Peru) to compare three scenarios: selective deconstruction (for reuse and recycling), recycling, and landfilling. Environmental impacts related to energy, water, and greenhouse gas emissions were quantified for each scenario.

Context: Residential building sector, urban housing

Design Principle

Design for Disassembly and Reuse: Buildings and their components should be designed with the end-of-life phase in mind, facilitating easy separation, recovery, and reuse of materials.

How to Apply

When designing new buildings or planning renovations, incorporate strategies that allow for the easy dismantling of components and the recovery of materials for future use. This could involve modular construction, standardized connections, and careful material selection.

Limitations

The study's findings are specific to the case study locations and housing typologies examined; broader applicability may require further research across diverse contexts and building types.

Student Guide (IB Design Technology)

Simple Explanation: Taking apart buildings carefully to reuse and recycle materials instead of just throwing them away can save a lot of energy, water, and reduce pollution.

Why This Matters: Understanding the full lifecycle impact of materials is crucial for creating truly sustainable designs. This research shows that how we deal with buildings after they are no longer needed has a huge environmental cost that can be significantly reduced.

Critical Thinking: To what extent can the benefits of selective deconstruction be realized globally, given the diverse economic, regulatory, and infrastructural landscapes?

IA-Ready Paragraph: Research by Keena et al. (2023) demonstrates that implementing selective deconstruction strategies in housing can lead to substantial reductions in environmental impact, with potential decreases in greenhouse gas emissions of up to 70% and water consumption by 67% compared to traditional landfilling. This highlights the critical importance of considering end-of-life scenarios in design to achieve true sustainability.

Project Tips

• When researching materials, look into their end-of-life potential and how easily they can be recovered or recycled.
• Consider how your design choices will impact waste generation and resource consumption during demolition and disposal.

How to Use in IA

• Use this research to justify the selection of materials or construction methods that support circularity and reduce end-of-life impacts in your design project.

Examiner Tips

• Demonstrate an understanding of the full product lifecycle, including end-of-life considerations, when evaluating design solutions.

Independent Variable: Deconstruction strategy (selective deconstruction, recycling, landfilling)

Dependent Variable: Greenhouse gas emissions, water consumption, fossil resource usage

Controlled Variables: Housing type, location (Global North/South), building material composition

Strengths

• Provides a comparative analysis of different end-of-life scenarios.
• Offers a North/South perspective on housing sustainability challenges.

Critical Questions

• What are the economic feasibility and scalability challenges of implementing selective deconstruction on a large scale?
• How do different material choices within a building affect the efficiency and effectiveness of selective deconstruction?

Extended Essay Application

• Investigate the potential for a specific building material or component to be designed for disassembly and reuse, quantifying the environmental benefits compared to its current disposal pathway.

Source

Implications of circular strategies on energy, water, and GHG emissions in housing of the Global North and Global South · Cleaner Engineering and Technology · 2023 · 10.1016/j.clet.2023.100684