Alejandro Aravena (l), Executive Director, Elemental (Chile) and Werner Sobek, Director, Institute for Lightweight Structures and Conceptual Design (ILEK), University of Stuttgart (Germany), at the inaugural Holcim Roundtable held at MIT Endicott House, Boston, MA, USA in 2014.
Guillaume Habert, Professor of Sustainable Construction within the Department of Civil, Environmental and Geomatic Engineering at the Swiss Federal Institute of Technology at the inaugural Holcim Roundtable held at MIT Endicott House, Boston, MA, USA in 2014.
John Fernández, Professor of Architecture and Building, Massachusetts Institute of Technology (MIT) at the inaugural Holcim Roundtable held at MIT Endicott House, Boston, MA, USA in 2014.
Vivian Loftness, Professor of Architecture, Carnegie Mellon University in Pittsburgh, PA, USA at the inaugural Holcim Roundtable held at MIT Endicott House, Boston, MA, USA in 2014.
The Roundtable brought together experts from different fields – material scientists, engineers, architects, sociologists, historians, policy makers, and industry leaders – to devise a clear agenda for retooling and reorienting construction towards a more sustainable future. The expert papers derived from the workshop are available below.
It is desirable that we reduce the harm and simultaneously maximize the benefits that the need for construction will inevitably produce for our societies and our environments. In order to reduce harm, we have to start by introducing more qualitative aspects into a field that tends to focus only on the quantitative aspects of a material’s negative environmental impact. In order to maximize benefits, we have to find a way for qualitative benefits to become more quantifiable.Download expert paper (PDF, 66.27 KB) »
The materials consumed in the construction industry are a key factor in addressing climate change. Calculating greenhouse gas emissions involved in the construction of a building should include “time” as a key factor in these considerations. A comprehensive view of sustainability must factor in the positive impacts (benefits or aspirations) and their maximization needs to be highlighted and placed in relation to the negative impacts (harm).Download expert paper (PDF, 108.07 KB) »
We need to clarify what “zero-material construction” means, why it is important, and who wants it – the viability of such a concept depends on whether we can contextualize its application. Modelling and scenario building exercises, or the compilation of such, are needed to establish base line and alternative material demand trends in different demographic and socioeconomic contexts. In addition, it is critical to identify a set of broader societal opportunities and barriers that hamper or enable the transition.Download expert paper (PDF, 177.23 KB) »
Some of the largest challenges to building (our cities) better are not necessarily the development of novel and appropriate technologies and solutions, or improved strategies, policies and measures – but rather finding competitive, transferrable, attractive and safe mechanisms for their implementation. This includes measuring non-financial benefits; transferring knowledge; making sustainable solutions aspirational; safe technology transfer and sustainable capacity building.Download expert paper (PDF, 111.05 KB) »
Traditional sustainability is still dominating the wider discussion: it is still about being less bad, minimizing damage, and reducing energy consumption. Instead of seeing humans as a burden for this planet, it is time to see them as an opportunity. Changing to a method of practice that creates beneficial footprints in turn allows designers to come up with an architecture that celebrates human life on this planet instead of merely minimizing ecological footprints.Download expert paper (PDF, 155.55 KB) »
While a lot of good, innovative work has been done and is being done, the construction industry still lacks the direction, information, know-how and incentives at the decision levels to achieve the scale required to truly make a difference in material consumption. To address these issues: data and information on material flows needs to be measured, gathered, validated and shared; knowledge needs to be packaged and shared at all decision levels of the industry; and material cost has to reach a level which makes the use of know-how and design time needed to reduce its use attractive.Download expert paper (PDF, 124.23 KB) »
We will need to dematerialize our currently unsustainable consumption of more than one world down to a goal of one, or less than one world for a population that will be expanding by at least two billion people in the coming decades. Dematerialization in the developed north presents very different challenges from that of dematerialization in the less developed and less affluent global south. Context for dematerialization is one of the most important aspects of this effort toward sustainability, enabling projection of resource needs, and determining how we should dematerialize.Download expert paper (PDF, 93.48 KB) »
A thorough (and global) mapping exercise in order to understand and expose the physical limits of material consumption and demand is essential – and a quantitative approach should be accompanied by qualitative appreciations of that same system. Most material flows cannot be understood solely by analyzing their production, trade and consumption patterns.Download expert paper (PDF, 530.43 KB) »
Determining the appropriate amount of materials to invest – considering the function of the building or the intimate relation between a very long service life of material and the loss of know-how once the building is done – is an argument against a dematerialization done without considering the associated immaterial flow of knowledge. Do the amount of materials used and their expected service life make sense? How much material and knowhow should we invest when we build our homes or when we build other iconic structures?Download expert paper (PDF, 108.88 KB) »
Financial power is no legitimation to use more materials from non-renewable and non-degradable sources than is absolutely vital. Whenever we start planning and building, we should ask ourselves: What would the world be like if this building – in its material use, energy use, and way of construction – would be multiplied a few billion times? A building’s manifestation on a material level is just as important as the immaterial impact, reflected in social relations and knowledge.Download expert paper (PDF, 192.09 KB) »
We need a robust understanding of urban metabolism: not just how much electricity or water is used, or how much waste is produced – but the intricate networks and cross-networks of flows and energies that make up an urban environment. These flows are not just about materials, chemicals, and capital, but about humans, ideas and institutions as well. The point is to help us see as many different interconnections as possible so as to improve our understanding of who we are in the world.Download expert paper (PDF, 110.82 KB) »
Embodied energy and carbon are not part of the dialogue in the design community, which highlights the need for increased literacy on material consumption in the built environment. This requires improved metrics to understand construction materials and their impacts; inspirational precedents to stimulate design ideas and technologies with dramatically lower carbon emissions; and breakthrough technologies that improve materials use with dramatically improved performance for lower environmental impact.Download expert paper (PDF, 119.51 KB) »
The material intensity of mainstream building practices is unsustainable, with material efficiency gains nullified by rapid growth in construction volumes to fulfill unmet demand and aspirational consumption. There is an urgent need to we-materialize so people become an integral part of the material production and application value chain; and to re-materialize so that material flows emanate much more significantly from waste that is generated within local communities, or through the intelligent use of composite materials, aeration and other innovations that rely on the laws of physics.Download expert paper by Shrashtant Patara, India (PDF, 104.14 KB) »
In order to be truly sustainable, we have to be more radical. We have to build houses in such a way as to make them “Triple Zero” – zero energy, zero emissions, zero waste. And we have to make them breathtakingly attractive and exciting. We can already achieve with the means presently at our disposal, there is no excuse whatsoever for building houses which are not at least energy-neutral. As sustainability becomes visible and comprehensible, it wins people’s hearts and minds, and thus also the opportunity for the implementation of sustainability on a broad basis.Download expert paper (PDF, 88.44 KB) »
We have political and economic systems that have successfully delivered an unequal, resource-intensive and environmentally-destructive material world organized into the urban form that is now facing a major crisis. Cities are the spatial expressions of the crisis of our material world, and the spatial concentrations of potential that need to be recognized and unleashed. Once the resource requirements of future urbanization and re-urbanization are calculated, the next step requires a realistic assessment of how we can dematerialize this urban future using a given set of technologies.Download expert paper (PDF, 277.54 KB) »
The building community must purchase, use and reuse materials with a far greater awareness of reducing harm and maximizing benefits. A clear set of harms and benefits that can be both quantified and qualified to help the building community achieve truly sustainable material decisions was identified.
The key elements of reducing harm are: source of materials matter and should capture economic, environmental and human cost-benefits of the extraction and production of materials and assemblies; distance matters and local materials have lower logistics costs, catalyze the local economy and are often more environmentally-suited to local climates; quantities matter where material or assembly must be renewable in a timeframe that is shorter than the life of its utilization.
The key elements of maximizing benefits are: humans matter where materials gain measurably in value where sourced and used to provide viable skills and empowerment, build capacity and provide living wages; environmental regeneration matters when materials are sourced and used to regenerate environments; innovation matters when materials and assemblies serve multiple purposes, providing integrated performance with less material; and time matters and the longer a material or an assembly provides service, the better the re-materialization.Download 1st Holcim Roundtable summary (PDF, 431.47 KB) »