Episode 48. AJ Climate Champions with Hattie Hartman and Joe Jack Williams. Structural engineer Eva MacNamara of Expedition Engineering explains how we can radically reduce our use of concrete and how to better understand the biodiversity impacts of material choices.
In this episode, we dive into the tricky topic of concrete and unpick the widespread mantra that ‘concrete is bad’. Concrete is ‘an addiction’ that has led to an obese construction industry, says Expedition’s MacNamara; it is not going to go away but we can radically reduce our use of it. She describes a porposed slab design for the Eden Project site in Dundee which would achieve an 80% reduction in concrete volume.
MacNamara stresses that ‘using less’ is much more impactful than substituting low-carbon concretes and notes that she repeatedly sees practitioners over-specifying. We discuss some of the nuances of concrete use: which applications are most appropriate, how to reduce the volumes we use, and why low-carbon concrete – especially GGBS – is not a silver bullet. We also touch on upcoming innovations including Seratech, ‘funnel’ slabs and smart crushing.
McNamara explains how to bring both carbon and biodiversity into the concrete procurement process. Highlighting findings from the recent report The Embodied Biodiversity Impacts of Construction Materials (Expedition/ICE, November 2023), she notes that 95% of biodiversity impacts occur off site and that the new biodiversity net gain requirements only address the 5% on site, so designers must look beyond a site’s boundary.
Finally, MacNamara advocates finding a place to innovate on every project. ‘We can make the most difference by using our projects as springboards for incubating innovation,’ she says.
For show notes and to catch up on all AJ Climate Champions episodes, click here.
Hawkins\Brown’s Louisa Bowles on what net zero actually means
Editional Studio on persuading domestic clients to build less and retrofit more
Bob Prewett explains why Passivhaus is often too much for heritage buildings
ACAN founding member Sara Edmonds on ramping up domestic retrofit
John Christophers on his zero carbon home, which generates a 40% energy surplus
Lessons from AHMM’s Stirling Prize-winning Burntwood School building performance study
Judit Kimpian on why building performance studies are crucial for net zero
AKT II’s Hanif Kara on CLT virtue signalling, concrete innovations and Bloomberg’s embodied carbon
Bangladeshi architect Marina Tabassum on why the climate crisis is not a north-south problem
Philippe Madec on combining sustainable development with Frampton’s critical regionalism
How France is pioneering contemporary architecture built from straw, hemp and thatch
Why France is increasingly building with bio-renewable materials – with Dominique Gauzin-Müller
Justin McGuirk on the Design Museum’s Waste Age exhibition and Kat Scott on the Architects Declare Practice Guide
Rachel Hoolahan on material passports for retrofit
Duncan Baker-Brown on mining the Anthropocene
COP26: Glasgow‘s plans for carbon neutrality by 2030 + ACAN‘s COP26 fringe activism
COP26 pop-up activism and Glasgow’s new climate resilient public realm
RIBA Climate Special with Simon Allford and Gary Clark
The 21st-century village: Sarah Featherstone and Jennifer Ross on VeloCity
Rewilding expert Isabella Tree on why a 3,500-home development must be stopped
Create your
podcast in
minutes
It is Free
Dear Alice | Interior Design
99% Invisible
The John Clay Wolfe Show
Gulliver’s Travels
The Count of Monte Cristo
How to Decorate
Creative Pep Talk