The Culture and Nature of Concrete
Concrete and social liberation are linked under modernity. This modest and ubiquitous building material has been able, with reinforcement, to redefine what urbanism looks like. Concrete is an ideologically mixed bag, witness large scale apartment tower blocks built in the post war period across big cities in Europe as they were in North and South America. Concrete was shaped, misshaped, celebrated, or maligned. The housing stock provided remains crucial; people have to live somewhere.
The Culture of Concrete
Concrete and social liberation are linked in modernism. This modest and ubiquitous building material has been able, with reinforcement, to redefine what urbanism looks like. Its origin story in concrete industry accounts goes back to Bedouins in Syria, perfected by the Romans with the recipe lost after that Empire collapsed but rediscovered in mid 19th Century France and perfected again in the United States. The concrete industry itself sees social liberation and its own shareholder value increase as intertwined. The Vicat Group Website writes: “Louis Vicat revealed the secrets of artificial cement in 1817 while building a bridge over the Dordogne River, between Souillac and Lanzac, in southwest France. He filed no patent and freely give advice to the architects and contractors of his time” (Vicat, 2023). Vicat is a French based, Paris La Défence headquartered, international publicly traded corporation, founded by the son of Louis, Joseph Vicat in 1853 with Vicat family members still involved on the Board of Directors and a capitalization of EUR 1,338 billion (https://live.euronext.com). Lafarge Cement is bigger, founded in 1833 by Joseph-Auguste Pavin de Lafarge with nearly ten times the employees, and is connected to the Suez Canal construction of the 1860s. Englishman, Joseph Aspdin is attributed with the invention of Portland cement in 1824, made by burning finely ground chalk and clay attribute until the carbon dioxide was removed. Aspdin named the cement after the high quality building stones quarried in Portland, England. In the 19th Century concrete was used mainly for industrial buildings.
The first widespread use of Portland cement in home construction was in England and France between 1850 and 1880. Joseph Monier patented the technique of reinforcing concrete in 1867 in France and Francois Coignet used the added steel rods to prevent exterior walls from spreading apart in domestic architecture. In the US, Ernest L. Ransome is celebrated by the American Society of Civil Engineers for his use of reinforced concrete since the mid-1800s, and his development of ways to increase its strength. In 1884, Ransome patented the use of twisted steel bars for the reinforcing of concrete and in 1903 the 16-story Ingalls Building in Cincinnati, Ohio is named as the world’s first skyscraper. By the mid 20th century, steel reinforced concrete defined the architecture of the era.
The Nature of Concrete: The carbon footprint of concrete production, the building construction industry and waste.
Carbon dioxide emissions from manufacturing new concrete requires power largely from fossil fuels, and the chemical process of making the cement portion of the concrete also produces significant amounts: roughly 620 Kg of CO2 is produced for every metric tonne of cement manufactured and 8 percent of the worlds CO2 emissions compared to 2.8 percent from aviation. 40 percent of global raw materials is consumed by building construction industry (BCI) while it generates about 40 percent of waste, emits about 25 percent of carbon dioxide (Oluleye et al.,2022). The process of cement manufacture involves heating kilns the size as long as a 40-storey building is high, large enough to fit a car into it with a diameter of 3.6 metres to 2,700 degrees Fahrenheit, or 1,480 degrees Celsius. “The finely ground raw material or the slurry is fed into the higher end. At the lower end is a roaring blast of flame, produced by precisely controlled burning of powdered coal, oil, alternative fuels, or gas under forced draft” the American Portland Cement Association explain with heroic prose (PCA, 2023). Certain (unnamed) elements are burnt off, red-hot clinker is produced. The carbon footprint of concrete disposal is being addressed in Europe with an emphasis on recycling. Estévez, Aguadoa, & Josaa (2006:1), using data from the EU around 1999 estimate “current annual production of construction and demolition waste (C&DW) is on the order of about 180 million tonnes, of which, about 28% is recycled.” Targets for recycling 70 percent of C&DW, or building construction and demolition waste (BCDW), are discussed in the Waste Framework Directive Waste Framework Directive (2008/98/EC) and a 2018 report commissioned by the Directorate-General for Internal Market, Industry, Entrepreneurship and SMEs. The EU Waste and Construction and Demolition Waste Protocol and Guidelines came into effect 2018 (European Commission, 2018; 2023). Resource efficiencies and opportunities for the building sector are outlined in these guidelines.
The market for C&DW/ BCDW in Canada is less developed as might be expected with the differences in scale between the two bodies, the two populations. The figures for percentages of solid waste produced by the construction industry in Canada in 2000 are identified as around 25 to 50 percent of municipal waste, 9 million tons of C&DW annually (Yeheyis et al., 2012). Environment and Climate Change Canada (Government of Canada) (EEEC, 2021) identifies the figure as 4 million tonnes of BCDW in 2021 without a clear account of how that figure was reached. Oluleye et al. make a strong case for the crucial importance of circular economy (CE) research and reform for the BCI as they emphasize the importance of Spain, Italy and Canada in conducting that research. The reduction of construction waste saves waste disposal fees or when recycled near building or demolition sites, which is relatively easy to do, transportation costs are less. “The extension of the useful life of materials through recycling has a cumulative advantage that spans beyond the building itself to the externalities, thus contributing to socio-economic and environmental development,” they argue (Oluleye et al., 2022:7). Retrofitting and repurposing existing buildings, as architects Lacaton & Vassal (2022) argue and practice, would reduce further the carbon footprint of the BCI, the BCDW and any recycling industry efforts. Existing buildings require however significant reductions in the energy consumption requirements of thermal control. Toronto-based The Atmospheric Fund (TAF) estimates that 44 percent of carbon emissions in Toronto comes from buildings (https://carbon.taf.ca).
Like with interventions by Lacaton & Vassal in Bordeaux or Paris, discussed in other posts, a report from 2012 by TAF underlines the site specific nature of any roll-out of retrofit strategies (Touchie, et al. 2012). Whereas the modernist apartment tower block could be characterized as a cookie cutter roll out of a certain concrete heavy urban density intensification, what is required urgently is a site specific, site by site sensitivity to the most cost effective approach to achieve both the carbon and cost reductions to domestic tower living, while ameliorating the living conditions of tower residents. The roll out of a post concrete utopia needs to be site by site, but be scalable and roll out across the region. Concrete is an ideologically and socially mixed bag, witness large scale apartment tower blocks built in the post war period across big cities in Europe, as they were in North and South America. Concrete was shaped into buildings that were celebrated as new, clean, and bold until the buildings came to be seen as ugly and were maligned. Many were built as inexpensively as possible and not well maintained. Yet, the housing stock provided was and remains crucial; people have to live somewhere.
The Culture of Retrofitting
The architecture industry and media in Europe and the UK are taking retrofitting and refurbishment of existing buildings seriously. The Royal Institute of British Architects (RIBA) have launched in 2023 a concerted effort to promote refurbishment with an award, the RIBA Reinvention Award (RIBA, 2023) and the argument for CO2 reduction from the refurbishment, and repurposing of existing buildings is expressed also a cost savings on the level of both the projects and the experience of fuel costs for thermal regulation living within them. The obligatory calculation of embodied carbon in new building development is also on the British government regulatory agenda, enacted in 2013 in the Netherlands, 2021 in France (Harrabin, 2023). The UK based Architects’ Journal (AJ) has been awarding retrofitting efforts under the rubric of the AJ Retrofit Award since at least 2012, with awards under different categories including housing. The 2021 award went to the refurbishment of 314 flats in three residential towers in Woodside, Glasgow, owned by the Queens Cross Housing Association with work led by Leeds, UK, based Engie Regeneration (https://www.engie.co.uk/). The price point per unit was under GPB 40,000 (CDN 67,000) with operational carbon emissions reduced by 70 percent. Expressed in the project aims was a concern for the mitigation of what in the UK is called “Fuel Poverty”, another term for energy poverty (EP). Residents not evacuated during or after the project completion was also noted by the award judges as an important factor in the Woodside project (Wilson, 2021).
The 2023 winner of the AJ Retrofit Award for Housing was the second retrofit phase by the architecture practice of Mikhail Riches of the historically listed Park Hill Estate in Sheffield, UK. Sheffield-Park Hill is a high profile modernist housing estate, the product of an ethos of slum clearance and intended as social housing that looms over the city both physically and emotionally for the people of Sheffield. The Park Hill estates, roughly 1000 flats completed in 1961 designed by Ivor Smith and Jack Lynn was built as a “slum” replacement to modernism ethos of the separation of cars from pedestrians, with recreation of ‘streets in the sky.’ For Sheffield it has been a high profile feature on the skyline of the city, and a council housing project that ran deep in local imagination. Witness the recent celebration of it and working class culture living within it in the form of a musical, Standing at the Sky’s Edge, first performed in Sheffield, 2019 and 2022, and then to be staged again London’s West End, 2024. This cultural intervention I include here to talk about the human experiences of living within the sorts of legacy tower neighbourhoods explored too in cultural terms. The musical, Standing at the Sky’s Edge is about families who lived there over generations, based on music from Sheffield’s own Richard Hawley from his 2012 album of that name (Akbar, 2023). The album is a simply gorgeous wall of sound like ballads of love and loss with flights of lead guitar soloing and a dynamic range covering a profound emotional one.
The 2019 review of the musical in The Guardian (Kalia, 2019) features a strong image of the phase one retrofit beside an unrenovated portion of the building. The UK Grade II listed “brutalist” building, as Kalia calls it, although it is not obviously brutalist— just big and made in large part from concrete—is seen in the theatrical review to reflect the lives of its working class residents. The utopian hopes of the 1950s are described with those very hopes declining with the downturn in the steel production industry in the later 1970s in the UK, and the post-industrial fortunes of the whole city. Current residents point to the socio-economic and demographic diversity of the phase one retrofit completed then but are also quoted by Kalia as saying it’s a Marmite situation: you either love it or hate it. The retrofitting comes at a cost seen as high by former residents, too high for some to move back in, an irony perhaps for an iconic working class housing form. It is an indication of inadequate governance of housing prices in the financial planning of the project and eco-gentrification of once publicly owned working-class housing. Fran Williams, writing for the AJ award announcement says: “As a project, it embodies everything these awards advocate: from decarbonisation to social sustainability” (Williams, 2023). The scheme for this phase of a further 195 units to the first phase of 260, involves a mix of market rate and subsidized housing, with the target of 20 percent “social rent” or subsidized housing hoped for (Wilson, 2022), significant upgrades to the building envelope to reduce thermal regulations cost. Energy efficiencies achieved in the refurbishing are not accounted for in assessing total housing costs, a question worth asking for further study. But this also a part of the conflict between social and environmentalist agenda setting in retrofitting housing. The practical argument for retrofitting in the UK context is made by an AJ initiative called RetroFirst, trying to balance that conflict (Hurst, 2019) and promote their thinking with a social media tag of #retrofirst. In a sort of manifesto, the campaign is aimed to promote taxation incentives to promote rather than block (as it presently does in the UK), policy around existing building promotion and recycling of materials and around public procurement policies.
The Consumption of Energy
Energy consumption is central to that argument, energy and emissions in the building process, the demolition process: the “substantial embodied energy savings made in repurposing existing buildings, compared with the ultra-high embodied energy costs of demolition and rebuild” (Hurst, 2019). Energy consumption reduction for the thermal regulation of the living space of the completed project is also part of that argument. In the North American context, the urban planning and architecture organization Urban Land Institute is promoting the retrofitting argument in its Summer 2023 issue of Urban Land (Lerner, 2023; Oestreich, 2023). The reduction of operating energy consumption is there added to the account, with numbers achievable with simply upgrades as significant as 20 percent. Residential towers in North America are not yet sufficiently on the radar, but need to be.
References
Estévez, B.G., Aguadoa, A., & Josaa, A. (2006). Environmental Impact of Concrete Recycling Coming From Construction and Demolition Waste (C & DW ). (Report). Frauenhofer IRB. https://www.irbnet.de/daten/iconda/CIB865.pdf
Harrabin, R. (2023, July 19). Riba Launch Reinvention Prize to Encourage Refurbishment Over Demolition. The Guardian. https://www.theguardian.com/artanddesign/2023/jul/20/riba launch-reinvention-prize-to-encourage-refurbishment-over-demolition
Hurst, W. (2019, September 12). Introducing RetroFirst: A New AJ campaign Championing Reuse in the Built Environment. The Architects’ Journal. https://www.architectsjournal.co.uk/news/introducing-retrofirst-a-new-aj-campaign championing-reuse-in-the-built-environment
Kalia, A. (2019, March 15). “Richard Hawley gets it!” Park Hill residents praise Sheffield musical. The Guardian. https://www.theguardian.com/stage/2019/mar/15/richard-hawley-gets-it-park-hill residents-praise-sheffield-musical
Lerner, M (2023). Retrofitting VS Replacing: Marking the Case for Sustainable Improvements. Urban Land. Summer 2023. Washington: ULI. PP 68-73.
Oluleye, B. I., Chan, D. W. M., Saka, A. B., & Olawumi, T. O. (2022). Circular Economy Research on Building Construction and Demolition Waste: A Review of Current Trends and Future Research Directions. Journal of Cleaner Production, 357 (Complete). https://doi.org/10.1016/j.jclepro.2022.131927
Oestreich, V. (2023). The Materials Movement: Advancing Low-Carbon, Healthy Materials for Sustainable Communities. Urban Land, Summer 2023. Washington: ULI. PP 74-79.
Touchie, M., Pressnail. K, Binkley, C. (2012). Energy Retrofit Opportunities for Multi-Unit Residential Buildings in the City of Toronto. TAF/ University of Toronto. https://taf.ca/custom/uploads/2018/02/University_of_Toronto_Report_Toronto_MURB_Retrof it_Opportunities_2012-11-22.pdf
Williams, F. (2023, April 4). AJ Retrofit Awards 2023 winners revealed. The Architects’ Journal. https://www.architectsjournal.co.uk/news/aj-retrofit-awards-2023-winners-revealed
Wilson, R. (2022, November 23). Park Hill Phase 2 by Mikhail Riches: Less vibrancy, more subtlety. The Architects’ Journal. https://www.architectsjournal.co.uk/buildings/park-hill-phase-2-by mikhail-riches-less-vibrancy-more-subtlety
Yeheyis, M. K. Hewage M.S. Alam C. Eskicioglu, R. Sadiq (2012). An Overview of Construction and Demolition Waste Management in Canada: A Life Cycle Analysis Approach to Sustainability. Clean Technologies and Environmental Policy · February 2012, 15:81–91. https://www.researchgate.net/profile/M-Shahria Alam/publication/257478981_An_overview_of_construction_and_demolition_waste_manage ment_in_Canada_A_lifecycle_analysis_approach_to_sustainability/links/5ef25dd892851cba7a4 2b266/An-overview-of-construction-and-demolition-waste-management-in-Canada-A-lifecycle analysis-approach-to-sustainability.pdf
