PURE RESEARCH: Architecture and Un-making At the 2019 launch of the RetroFirst campaign, the Architects’ Journal reported ‘Worldwide, the construction industry consumes almost all the planet’s cement, 26 per cent of aluminium output, 50 per cent of steel production and 25 per cent of all plastics...We lose more than 50,000 buildings through demolition every year and, while more than 90 per cent of the resulting waste material is recovered, much of this is recycled into a less valuable product or material, rather than being reused.’

Here Helen Taylor explores architectural attitudes towards reuse, recycling, and the circular economy.

Anyone who has seen the Lego movie will know all about the “kraggle”- the mysterious powerful negative force that turns out to be (spoiler alert) glue. The way materials are stuck together is also a challenge in the real world of un-making. The earth is a closed system with limited finite ‘mineral’ resources. The climate emergency and the vital need for carbon reduction also applies to our thinking about materials, their value and how we retain it. Despite the efforts taken to develop and deliver site waste management plans, and encourage recycling, data actually shows a significant reduction in the re-use of construction material over the last 20 years. There are many reasons for this from bricks being laid in concrete mortar that can’t be reused, to a lack of provenance, and to reclaimed materials not being specified.

This situation is driving some of Scott Brownrigg’s key sustainability themes:

Resource Depletion: Resource use in both construction and operation needs an increased focus. This attitude applies to the specification of materials from sustainable, ethical sources and targeting the use of locally sourced, retained, reused or recycled materials wherever possible.

Circular Economy: The industry needs to be transformed from a construction project based focus to become wider built environment guardians- and to design for the whole project lifecycle. The AJ RetroFirst campaign aligns with our approach, considering reuse and refurbishment first, but also designing for reuse, adaptability and – increasingly - for deconstruction and disassembly . Considering every building as a material bank. This approach means that materials built-in to a project must be capable of being economically dismantled for reuse, which impacts material selection and fixings. 

Healthy Environment: As we have seen during the recent and ongoing pandemic, a healthy environment is vital for our physical and mental health and the heath of the planet. Preventing pollution of air, water and land is critical. Consideration of the lifecycle of construction materials must include consideration of potential pollution during that life such as:

• Disturbances to the existing environment, whether on green field or brown field sites
• Specification of materials during the design stage and associated need for plant, processes and techniques within the construction stages
• Manufacture and transport of materials and products
• Handling and use of materials on a construction site
• Pollution from the operation of the built environment (sewage, waste etc.)

Each of these activities poses a risk of introducing pollutants into the environment which can affect the workers on site, the neighbourhood, or the local ground, water and air quality. Our environment is the largest determinant of overall health, therefore the built environment has a key role to play in relation to our health and wellbeing as well as that of the planet.

In the developed world, we spend approximately 90% of our time within buildings and are therefore exposed to a range of chemicals arising from furnishing and finishes. The WELL Building Standard® is an increasingly popular evidence[1]based system for measuring, certifying and monitoring the performance of building features that impact health and well-being. Our team of WELL Accredited Professionals provide advice and guidance for projects that includes material design and specification as a key element of accreditation requirements.

The quality of both design and construction matters to managing material resources. Post-Grenfell remedial works are uncovering that buildings were not put together the way they were designed. Our Technical Advisory Group are addressing projects completed relatively recently where investigation reports show inadequate insulation was installed, for example. If the materials used are brick slips embedded in an insulation and rain screen cladding. It is a challenge to upgrade and repair without a significant material waste. Retrofitting projects started for fire safety reasons quickly turn out to uncover much further reaching issues, calling into question what owners of such buildings should and can do in terms of maintenance. The way the buildings are put together, and the difficulty of disassembling them for repairs, leads many to turn to demolition and starting again. An enormous waste of embodied carbon which cannot be recovered.

As a result of Grenfell, the regulatory changes in the draft Building Safety Bill propose to further increase the involvement and responsibility of the Principal Designer (PD) required by Construction Design Management (CDM) regulation in the UK. Under CDM currently, the PD co-ordinates health and safety (H&S) in relation to the design (whenever this occurs), makes sure designers have taken account of H&S “so far as reasonably practical” (SFARP) and ensures everyone in the project has the information they need to do their tasks safely. Under the Building Safety Bill, the PD will have to verify that every aspect of the design has been delivered exactly as the drawings and specification and that it complies with Building Regulations. The PD can only do this if they have the expertise and if they have been on site to see every nut bolt and screw put in place throughout the entire construction phase. This is a challenge to the industry in terms of expertise, liability and insurance. However, it would lead to the situation where the building information contained in the Health & Safety (H&S) 9 file at handover, and the digital twin, will be a completely reliable document of the make-up of the building and become the manual you use when you take it apart, or repurpose. For example, embedding the performance data of a beam in the digital twin means that when it comes to be reused the strength is known, without need for testing and verification. An ecosystem of digital twins and digital material passports will become a crucial part of managing our built environment as well as supporting carbon reduction.

The drive to modular and off-site construction can address issues such as build quality and reduction of negative construction impacts. However, these need to be designed with the circular economy in mind. Efficiencies gained in early stage construction cannot be at the expense of later adaptability and material recovery. This means appropriately sized modules and components, fixed together to reflect the life-cycle of each layer as set-out in Stewart Brand’s Shearing Layers diagram. “Cradle to cradle” or ‘take back’ schemes can be specified to support the reuse of materials in the lifecycle of the building.

Moving to a truly circular economy in the built environment will only work if all parties involved are part of it. We need a systemic shift in terms of supply chains and value. As architects and designers we are already starting to address the technical challenges and make the fundamental shift in our attitude to materials- seeing buildings as material banks.

Illustrations

Victoria gate - construction image

We took an original Scott Brownrigg designed building from 1985 and redeveloped it for the 2018 market- retaining as much as possible of the existing structure but replacing the façade and interior finishes and adding 25% to the footprint with an additional floor.

Lego models of Seward Park New York

Lego is immensely versatile and doesn’t age. Older and newer sets can be blended and recycled endlessly. A great vision for building products and materials.

Layering diagram - with thanks to Stewart Brand’s Shearing Layers diagram

A building is conceived as several layers of longevity of built components. The lifetime of different elements of a building can vary from well over a hundred years down to a matter of months, or even weeks. The structure of the building has the longest potential lifespan and is the limiting factor in adapting a building to a new use. The structure and fabric can be made to be adaptable and over-engineered to last a lifetime, while the internals will be fickle and have to be designed to be reusable or compostable. Keeping each of the layers independent allows the structure to be retained when upgrading the fabric and the building will be easier to disassemble at end-of-life so that the components can be reused, remanufactured or recycled. Using the layered approach helps to make the building easier to maintain, as the services will be more accessible for repair and maintenance.

Stora enso office concept

The flexible timber office developed in collaboration with Stora Enso uses a modular, kit of parts approach pre-assembled to ensure transport to site in optimised loads. Simple and quick to construct using a clip system it is completely demountable and the timber frame is reusable.