UK Government to Regulate Embodied Carbon (Maybe)

According to The BBC, the British government's building strategy will look at embodied carbon. Roger Harrabin of The BBC explains: "Developers may have won praise in the past for demolishing draughty buildings for energy-efficient replacements. But engineers now say existing buildings should be kept standing due to the amount of carbon emitted when original building materials were made - known as embodied carbon."

Treehugger has noted before that when you plan or design with upfront or embodied carbon in mind, you shouldn't demolish perfectly good buildings and replace them with bigger ones, because of all the carbon released in making the materials for the replacement.

We have noted the  Architects Climate Action Network (ACAN)'s call for regulation of embodied carbon, with "whole life-cycle carbon assessments to be completed at the early design stages, to be submitted as part of pre-application enquiries and full planning submissions for all developments."

The BBC notes (and this is often misunderstood and usually poorly explained) that embodied carbon is coming to dominate the footprint of buildings.

"The engineering giant Arup calculated around 50% of the whole-life emissions of a building could come from the carbon emitted during construction and demolition. And this proportion will only grow as buildings are increasingly cooled and heated using low-carbon electricity – shifting more of the carbon burden on to the construction process."

Treehugger covered Arup's report earlier, quoting one of the authors, Chris Carroll:

“We have to consider carbon like we currently consider money. The idea that you would build a project and not know how much it costs financially would seem incredible. But the industry currently doesn’t know where it stands when it comes to carbon emissions, making it difficult to set meaningful targets and drive progress."

In fact, the embodied carbon can be much higher than that, with some studies putting it at 76% in modern buildings.

It's time to regulate this

As a post in Archinect last year pointed out, regulations about embodied carbon are few and far between. We have been complaining about this for so long, quoting ACAN often:" We must act now to regulate embodied carbon in line with our commitments to tackle the climate crisis, requiring all projects to report whole life carbon emissions." But nothing much ever happens, even in this time of climate crisis, primarily because there are so many competing interests.

For example, there is a huge need for more housing in the City of Toronto, where I live, and there are government policies in place to increase density. But they pile all the allowable density into pockets away from all the single-family houses, so you get developers applying to tear down perfectly good 23 story buildings like the one on the left, to be replaced with towers twice as high, and which have to be built out of concrete.

This building being demolished for more condos was the Toronto headquarters for the Royal Canadian Mounted Police, bomb-proof and built in 1972 to last a century. When they moved out it was converted to a hotel. There is so much concrete that it took forever to demolish. But nobody gives embodied carbon a moment's thought.

When you try to explain the problem of embodied carbon, they say "It's old concrete, now, The carbon was emitted decades ago. It is water under the bridge." If they were building a park and not replacing the building, they would be right. But instead, there it is going to be replaced with a new building, made with concrete that has upfront carbon emissions of 400 pounds per cubic yard.

In a world where you think about upfront carbon emissions happening now, you would repair and retrofit the buildings you have, and you would increase density with low and mid-rise buildings all over the city, made of low-carbon materials like wood, instead of protecting single-family zoning.

I asked architect Toon Dreessen, who is a past president of the Ontario Association of Architects and knows his way around the regulatory systems for a few thoughts, and he sent me more than a few, noting the importance of existing buildings, and why we should make them last longer. He is speaking from Canada, but the concepts are universal.

• Investing in existing buildings has the potential to reduce carbon costs, as well as disruption to communities, by renovating with deep energy retrofits. This conserves the investment we’ve already made in the built environment, recognizing the long-term view governments can take in buildings.
• Buildings are physical manifestations of our culture; what we build says a lot about what we value as a society; retaining and conserving older buildings, be they Victorian or mid-century modern buildings, we conserve not only the building, its craft (often of things that we can’t replicate today, but also honor our cultural history. Even when that cultural history is hard to live with, it provides an opportunity to learn from our past, reflect on it and take steps to repair our cultural relationships
• Government is uniquely positioned to lead on this: publicly owned assets are often the product of carefully worked design ideas, and, historically, were creative opportunities for new ideas; adaptive reuse, deep energy retrofits, and carbon reduction strategies further advance those creative ideas. Traditionally, government buildings were high-quality design, even for mundane, utilitarian uses (think RC Harris Water Treatment, Lemieux Island Water treatment plan). The carbon cost to demolish and replace out of a sense of expediency is far greater than conservation; contemporary buildings tend to (or at least appear to) be designed for much shorter lifespans, in part because we drive costs to the bottom in both designs (low fee, low effort) and capital cost reductions to stay “on time and on budget” using composite, short life-span materials (ie, aluminum composite panels exposed to road grit, spray from deicing salt and wind that fail after 20 years versus masonry that lasts for hundreds).

Back in the United Kingdom, the Architects Journal has been leading Retrofirst, a campaign to stop demolition and promote reuse and revitalization of existing buildings. Will Hurst wrote:

"Demolition is the construction industry’s dirty secret. Despite all the declarations of climate emergency and talk of a green recovery, it is propped up by outdated rules and taxes and great swathes of our towns and cities are currently earmarked for destruction. If the government really means to “Build Back Better” it must recognise that conservation of buildings is now a climate issue and introduce reforms to ensure that bulldozing buildings is an absolute last resort."

New rules for a new way of thinking about building

The British Government is thinking about this issue, but everyone has to, everywhere, and it is a bigger picture that goes beyond the building walls. The Architects Climate Action Network listed principles that should be encouraged, repeated here:

1. Reuse existing buildings: Pursuing a strategy of retrofit, refurbishment, extension, and reuse over demolition and new build.
2. Build using less material: Designing more efficient and lightweight structures and designing out waste.
3. Build using low carbon materials: Use materials that have low or close to zero embodied carbon emissions.
4. Build using certified recycled material: Moving towards a circular economy and reusing building materials and products derived from low-carbon recycling processes that can be repeated almost perpetually without quality loss.
5. Build using long-lasting and durable materials, designed for easy disassembly: Avoid products that require frequent maintenance or replacement but that can be dismantled for reuse.
6. Build flexibly and for future adaptability to allow for the re-purposing of buildings.

I would add one more that goes beyond the walls of the building:

• Planning and zoning rules should be changed to permit low and midrise multiple-family dwellings built of low-carbon materials everywhere in our cities.

The issue of embodied and upfront carbon doesn't end with buildings. It means changing the way we think about everything. And it seems that finally, governments are beginning to take it seriously. Because as Julie Hirogyen of the UK Green Building Council told the BBC, “We really must come to grips with the issue of embodied carbon in buildings – we’ll never hit our climate targets unless we do."