Concrete is a Dirty Word
Recently, Greg participated in the "Decarbonization at Scale" talk at the Center for Architecture with fellow ULI members.
Talks like these give us the chance to collaborate with industry partners and explore large and small ways our work can better support environmental goals. Our number one takeaway from this talk was that we must be a part of tackling the concrete problem.
Concrete has come under scrutiny due to its significant environmental impact. Its production is one of the largest sources of carbon emissions globally, leading to growing calls for more sustainable alternatives.
Look around your environment, and you can see just how reliant we have become on this singular material.
Sand, a crucial ingredient in concrete, is becoming increasingly scarce due to over-extraction and environmental degradation. This scarcity exacerbates the challenges associated with concrete production.
Why Is Concrete So Carbon Intensive?
Concrete's carbon footprint arises from several stages:
Raw Material Extraction: Quarrying and mining for raw materials like limestone, clay, and sand require energy and contribute to habitat disruption.
Chemical Manufacture of Cement: Cement production is highly energy-intensive. The process involves heating limestone and other materials to high temperatures in a kiln, releasing significant amounts of CO2 through burning and energy consumption.
Transport: Transportation of aggregates (sand, gravel), water, and cement to manufacturing companies involves further fuel consumption and emissions.
Manufacturing and Transportation: Concrete must be mixed and transported to building sites, adding further carbon emissions.
Demolition and Recycling: The end-of-life stage of concrete—demolition and potential recycling—also consumes energy and often results in further emissions.
Changing Materials, Changing Values
With the rise in awareness about the environmental impacts of concrete, there is a shift towards alternative materials with a lower carbon footprint. To reduce our reliance on concrete and embrace more sustainable practices, Bayview’s material selection approach is:
Minimize Concrete Use: Assess whether concrete can be reduced or replaced in design projects. For instance, explore alternatives for footings and structural elements.
Stone Pavers vs. Concrete: In many cases, stone pavers can be a more sustainable option than concrete. They offer durability and a lower environmental impact. This is especially true with residential projects that require fewer materials. Though concrete is cheaper, stone provides superior longevity and aesthetic benefits.
Granite vs. Concrete: Granite can be a more sustainable choice for urban hardscapes. It is durable, easy to clean, and can serve multiple functions (e.g., as bollards, benches, and pavement), reducing the need for multiple materials and contributing to a more sustainable urban environment.
Holcim Foundation and Their Mission
The ULI talk was sponsored by The Holcim Foundation, which focuses on promoting sustainable construction practices. Its mission is to drive innovations in building materials and methods that reduce carbon emissions and improve overall environmental performance. The foundation supports research, offers fellowships, and encourages collaboration among industry leaders to advance sustainable building practices.
