We are researching the best natural materials & regenerative designs to use for our Community Learning Centre. Minimal environmental impact to people, planet and plants are at the heart of our project. We are aiming towards a circular economy and away from the linear ‘take-make-waste’ system mostly used in the construction industry. We also aim to follow the Living building Challenge, the Lean, Mean, Green approach and to ‘Design for Deconstruction’.
The Living Building Challenge
The Living Building Challenge is an advanced measure of sustainability in the built environment that offers a regenerative way of thinking about design and construction that is rooted in place and (re)connects people with nature.
The Challenge is grouped into seven key performance categories, or ‘petals’ to be considered in regenerative design:
Place – to be informed by and align to the characteristics of a building’s setting and landscape
Water – buildings should be independent, and operate within the water balance of a given place and climate, taking only what they need and cleaning what they put back into the ground
Energy – buildings should generate 105% of their own energy without using any combustion
Health & Happiness – to create environments that optimise physical and psychological health and well being
Materials – to ensure no toxic materials are used in the construction of a building
Equity – buildings should be just and accessible for their users and for those who build them
Beauty – to celebrate design that uplifts the human spirit and provides connections with nature. Architecture should inspire and educate future projects and generations
The Green, Mean, Lean approach to building:
The “Mean Lean Green” philosophy aims to produce developments that lower the demand for resources, provide efficient structures and deploy innovative technology.
It is based on the hierarchy:
Mean. Reducing the demand for materials, energy, water and other resources. For example, creating guidelines for building designers to ensure demand is low from the outset, by utilising passive measures such as natural heating, lighting, ventilation and external shading.
Lean. Ensuring that materials and systems are used responsibly and efficiently. For example, reducing distribution losses for energy (or water) between generation and usage. This might involve supplying heat, cooling, power and water from an on-site source.
Green. Supplying any remaining requirements from renewable sources to minimise residual carbon emissions. For example, solar power or rainwater harvesting.
Design for Deconstruction
‘Design for deconstruction’ is an important part of green design and a consideration of the complete life-cycle of a structure. It includes provisions for the re-use of building components at the end of a structure’s life. In 100 years time our building might still be standing, but if it ever has to be knocked down, we would like construction landfill waste minimised.
Circular Economy:
In our current economy, we take materials from the Earth, make products from them, and eventually throw them away as waste – the process is linear. In a circular economy, by contrast, we stop waste being produced in the first place. The circular economy is based on three principles, driven by design:
- Eliminate waste and pollution
- Circulate products and materials (at their highest value)
- Regenerate nature
It is underpinned by a transition to renewable energy and materials. A circular economy decouples economic activity from the consumption of finite resources. It is a resilient system that is good for business, people and the environment. The circular economy is a systems solution framework that tackles global challenges like climate change, biodiversity loss, waste, and pollution.
Working with Volunteers
We are keen to offer opportunities for volunteers to help build. This creates a symbiotic relationship between people and nature and brings about community cohesion. Hopefully, it also makes the building costs cheaper!
Researching Natural Building Methods
Strawworks provides information on all natural building materials
Some wonderful examples of community buildings built using natural materials
Rammed Earth
Rammed earth it’s a beautiful, affordable, locally sourced sustainable construction material which reduces our dependence on cement. The oldest earth-building remains are around 8,000 years old, but rammed earth has some notable long lasting examples. Most of the Great Wall of China is either rammed earth or has a large component of rammed earth as its basis. The Chinese found 2,000 years ago that in labour creation and resource management, earth could not be bettered. Also the Alhambra in Grenada in southern Spain is largely built using rammed earth, a mere 1,200 years old! But in terms of normal domestic use and in Northern European climate conditions, there are thousands of examples in England, France and Germany of at least 200-year-old buildings, as much as 7 stories high.
It involves removing all the topsoil first and accessing the rab earth below so it’s important to check how far down the rab soil is before you build and to ensure you have enough space to use the topsoil. Initally we planned to use rammed earth for the walls of our building but it was later realised that rammed earth wasn’t suitable for the small space as a huge amount of top soil earth would needed to have been removed in order to reach the rab earth and there was no space for this to be done. It was deemed unsustainable for this particular build has it would have required over a 50 truckload trips to remove aprox 400 tons of soil. However we are still hoping to use rammed earth in the ramp and outer buildings and frees up the inner wall to trial other materials such as helpcrete and wattle and cob for example.
Hempcrete
Hempcrete is made from the woody ‘shivs’ of the hemp plant, with lime added. It is a sustainable material. Not only does hempcrete provide exceptional thermal performance, significantly reducing operational carbon emissions through the lifetime of the building, but in terms of embodied carbon it is actually a better-than-zero-carbon material. This means that more carbon is removed from the atmosphere and stored in the material than is emitted by its production and installation on-site.
More info //www.ukhempcrete.com/
Cob
Cob is a natural building material made from subsoil, water, fibrous organic material (typically straw), and sometimes lime. The contents of subsoil naturally vary, and if it does not contain the right mixture it can be modified with sand or clay. Cob is fireproof, resistant to seismic activity, and uses low-cost materials. It can be used to create artistic and sculptural forms, and its use has been revived in recent years by the natural building and sustainability movements.
More info on www.cobcourses.com
Cob materials and advice available on //earthblocks.co.uk/ – based in St Austell
Strawbale
Straw is the perfect material to work with as it is in itself a waste product, it sequesters (‘locks in’) carbon and can be composted at the end of a building’s life.
A great example of a community building built with straw and volunteers.
Straw as an insulation material – showing impressive stats carbon impact.