Natural Structural Materials: Super Tall Timber

Lead Research Organisation: University of Cambridge
Department Name: Architecture


I envision a sustainable future in which natural materials play an increased and central role in the construction of the built environment. The fundamental premise of my research is that innovative approaches to research, processing, modification and design of natural materials can increase their role in constructing our future. Throughout history timber and other plant-based materials have played a major role in domestic construction, and still do around the world, but as the global population urbanizes, people live more densely in taller buildings. I believe we can make such tall buildings more naturally.

This proposal seeks to further the structural engineering knowledge necessary to make tall timber buildings a reality. The research funded through this Big Pitch proposal would enable the use of natural materials in taller and larger buildings as a substitute for steel and concrete, and to reduce the carbon emissions associated with them. Natural materials are uncommon in the built environment beyond a domestic scale, but my research suggests these materials have unmet potential as more sustainable alternatives to steel and concrete. Others share this view: there has been significant recent interest in tall timber, although "tall" in contemporary timber buildings is up to 10 stories; this height is barely midrise in steel or concrete. A proposal by Skidmore, Owings and Merrill for a 125m building of timber and a newly announced $2 million design competition by the US Department of Agriculture for wooden skyscrapers extend the interest. There is an aspiration to construct the tallest timber building that should be accompanied by research excellence.

Planned Impact

Tall timber buildings are becoming a reality, and we have a real opportunity to lead this area. This proposal is a step in that direction. With proper integration, this research will have a significant impact because it will have both academic research "push" and practical industry "pull" into the market. Within the context of the EPSRC Review of Ground and Structural Engineering, this proposal makes contributions in a number of areas: timber engineering is an area where the UK leads in consultancy, but needs to continue to develop the academic research to further our knowledge and ensure continued excellence. Advanced research on timber high-rise will help address structural design excellence in the academic community. The engineering impact will be in greater understanding of the design of tall timber structures, while the economic impact could be toward higher-value use of timber materials. The UK produces over 10 million tons of timber, and is the third largest importer of timber in the world [2]. The environmental benefits should be clear - timber buildings are lighter than equivalent steel or concrete ones, so foundations can be smaller, the material is a carbon sink, and by many measures, the processing of timber is less carbon intensive than steel or concrete. The raw material is available as a sustainable and expanding resource.


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Description Humanity's most consumed material, after water, is concrete. By using engineered timber our research shows that we can fundamentally transform the way we build, substituting conventional carbon intensive manufactured materials with naturally based ones, on a global scale. This allows us to blend traditional knowledge systems of construction with innovations in engineering to make timber skyscrapers a reality.

At the smallest scale our research group explores how the molecular structure of wood contributes to its macro-scale attributes. We found that thermal and chemical modifications alongside polymer impregnation experiments could yield enhanced high dimensional stability, fungi resistance and hydrophobic properties in timber - all contributing ultimately to enhancing its life and structural performance.

At the macro scale, we continue to develop a variety of engineering innovations to realise super tall timber construction. Here, a 'systems thinking' approach takes precedence: from considering forests as part of a supply chain for timber to developing modular off-site solutions and digital workflows that make use of regional transportation systems for optimal delivery and on-site assembly using prefabricated components.

By bridging the two scales, our holistic approach bolsters significant potential for plant-based construction materials on a large scale that can help reverse historic carbon emissions.

Timber is the only building material we can grow and every tonne of timber expunges 1.8 tonnes of carbon dioxide from the atmosphere. If all new homes in England alone were constructed from timber, we could capture and offset the carbon footprints of around 850,000 people for 10 years.
Exploitation Route The group's research is quintessentially interdisciplinary. Timber is a timeless building material with a strength parallel to that of reinforced concrete. And yet its potential in the building industry remains largely untapped.
The key to unlocking this lies in understanding its genetic, cellular and macro-scale properties simultaneously. Similarly, developing ideas for constructing timber skyscrapers, without resolving resistance to their uptake in industry, would limit our work to a purely academic exercise. Thus, our aim has been to blend architectural design and scientific research across scales and develop solutions that trickle down from timber skyscrapers to a variety of other typologies such as schools and affordable housing.
Our partnerships with architecture and engineering firms in the UK and the U.S.A. led to the co-creation of conceptual designs for timber skyscrapers in three locations: London (300 m), The Hague (150 m) and Chicago (243 m). Professional contributions by contractors and materials manufacturers guided the refinement of connection designs, optimizing of building component sizes for prefabrication and their transportation using regional waterways for realisation of novel concepts on sites.
Simultaneously, pioneering research by members of our biochemistry team unravelled critical xylan and cellulose interactions in 3-dimensions which have greatly enhanced our understanding of cell wall architecture that determines a plant's mechanical properties. Likewise, the chemistry team worked with acetylation and polymer impregnation of wooden surfaces to enhance timber's moisture resisting properties. Materials scientists in the group conducted life cycle analyses of engineered timber and its resinous composition to ensure that a negative carbon footprint could indeed be achieved at the skyscraper scale.
The project's findings demonstrate that supertall timber construction is not only beneficial for the environment while alleviating the housing crisis but that it can also be cost effective and innovative. Working across sectors, with partners within and without the academy, has added multiple valuable perspectives for maximising the real-world footprint of the project.
Sectors Construction,Creative Economy,Environment,Manufacturing, including Industrial Biotechology

Description project demonstrated the potential to use natural materials in taller and larger buildings as a substitute for steel and concrete, and to reduce the carbon emissions associated with them. Natural materials are uncommon in the built environment beyond a domestic scale, but our research suggests that these materials have unmet potential as sustainable alternatives to steel and concrete. The Supertall Timber project resulted in the RIBA President's Award for Research designs for timber skyscrapers that have captured the public imagination, and numerous publications on timber engineering and its future. We continue working with partners from that project on this one, and widen the range and disciplines of our partners.
First Year Of Impact 2016
Sector Construction,Creative Economy,Education,Environment,Manufacturing, including Industrial Biotechology,Other
Impact Types Cultural,Societal,Policy & public services

Title Research data supporting 'Penellum, et al. Relationship of structure and stiffness in laminated bamboo composites, Construction and Building Materials, 2018' 
Description Raw data in excel sheets presenting bending siffness and fibre volume fraction of processed engineered bamboo beams. 
Type Of Material Database/Collection of data 
Year Produced 2018 
Provided To Others? Yes