Interlocking Crises of Climate, Biodiversity and Housing
The world is facing twin crises of climate change and biodiversity loss, and of the numerous social and political crises countries are dealing with housing is perhaps most significant. Solutions for these are inextricably linked.
To mitigate climate change we need to reduce carbon emissions to net zero by mid-century and a critical part of that is to make our homes radically more energy efficient. To do that, global supply chains will have to hugely increase production of building materials like insulation. However, the manufacturing process is also a major source of carbon emissions, defined as embodied or upfront carbon, whilst the mining and processing of resources is one the biggest causes of biodiversity loss through pollution and exploitation of natural resources. Housing development also contributes to biodiversity loss when it’s built in ways that destroy wildlife habitat, alter natural flood paths, or generates toxic waste.
Making less stuff is an important way to reduce carbon emissions and environmental impacts, but it is impossible to avoid the need for more and better housing. Safe and secure housing is a basic human need and the World Economic Forum estimates we will need 2 billion new houses by the end of the century. We will also have to retrofit most of the current 2.3 billion houses to make them more energy efficient and climate resilient.
What do we need to change in housebuilding?
To build a house of a certain size you need roughly the same quantity of materials regardless of the method you use to build it. Some methods might reduce the amount of waste generated on site, which is a positive sustainability outcome, but that doesn’t change the amount of materials in the finished product, typically about 1 tonne per square meter. So it is critical that we transition to materials that rate highly for sustainability.
Insulation is the one material that we do need to use more of, lots more. New-build houses need to include significantly higher levels of insulation than regulations currently require in most countries to meet net-zero targets, whilst existing houses that might have no or minimal insulation need to be retrofitted to as high a standard as practical. But the insulation products that dominate the industry are generally not sustainable in their manufacture: they are typically petrochemical based or otherwise have high embodied carbon, pollution or health impacts. The obvious alternative is bio-based insulation made from materials such as plant and animal fibres.
Bio-based materials could be directly substituted for the vast majority of insulation currently used in new-build homes. The thickness of insulation required may be different but the fundamental construction process would be unchanged. At the moment bio-based materials account for only about 1% of insulation used in the UK or US, slightly higher in Europe.
How does this fit with emerging trends?
There is no shortage of reference points for policies and guidelines to indicate that bio based insulation should be a priority issue, but there is little evidence of these being put into action. Most relate to embodied carbon or circular economy issues, but there are some specific to bio based materials.
- RIBA 2030 Climate Challenge
https://www.architecture.com/about/policy/climate-action/2030-climate-challenge - UKGBC Net Zero Whole Life Carbon Roadmap
https://ukgbc.org/our-work/topics/whole-life-carbon-roadmap/ - LETI Climate Emergency Design Guide
https://www.leti.uk/cedg - The AECB CarbonLite Standards
https://aecb.net/the-aecb-carbonlite-standards/ - UK Net Zero Carbon Buildings Standard
https://www.nzcbuildings.co.uk/pilotversion - Future Homes Hub: embodied and whole life carbon implementation plan
https://www.futurehomes.org.uk/embodied-and-whole-life-carbon
Workshop schedule
The schedule allows for extended round table discussion on the three defined issues of construction details, supply chain and system change, with a closing discussion to summarise the key issues identified.
10.00Â Â Welcome + Introductions
10.10Â Â Discussion #1. Construction Details
Demonstrate how to substitute bio-based materials in mass market housebuilding: this could be done through standardised details with certified compliance for thermal, acoustic and fire performance, what we call Accredited Details.
Prompt: Ran Boydell, Ecohus, Sustainable Value Engineering
10:50Â Â Discussion #2. Supply Chain
Demonstrate how the manufacturing sector could deliver the quantities of material that the housebuilding sector would require. This includes all stakeholders in the supply chain, and also allow like-for-like substitution between comparable materials, that being a critical aspect of the procurement process.
Prompt: Max Chipulu, Edinburgh Napier University, Sustainability Orientated Innovation
11:30Â Â Break for tea + coffee
11:50Â Â Discussion #3. System Change
Identify what parts of the political, financial or social framework need to be influenced to enable this transition. The inclusion of embodied carbon targets in planning or building regulations is the most obvious case, where bio-based materials would significantly outperform current industry norms.
12:30Â Â Summary – What are the key issues and how could we progress them?
13:00Â Â Close
Key information
Date: Friday 18th October 2024
Time: 10:00-13:00
Location: ECCI, Infirmary Street, Edinburgh EH1 1LZ
How to register: By invitation only. Contact Ran Boydell of ecuhus at +447847300762 or rb@ecohus.net to enquire.
This event is a fringe event of ASBP’s Natural Fibre Insulation Week 2024