By Alissa MacMillan
Q: Is it better for the environment to refurbish old structures or to go for a new, energy-efficient build?
A: For quite a few reasons, restoring old builds is better for the environment, says architect and urban planner Dr. Philip Crowe, lecturer in Climate Responsive Design at University College Dublin. In answer to your question, he focuses on two ideas: the embodied carbon associated with builds and community resilience.
First, the science. Not as widely understood as things like renewable energy, “embodied carbon is a mathematically quantifiable way to justify the reuse of buildings,” Crowe explains. Embodied carbon is all of the carbon that goes into a building and building site, from the extraction of materials out of the earth to their transportation, construction on site, and refurbishment.
Greenfield sites – those new developments, often just outside cities and towns, often extending across many fields – require access, water-pipes, and more; a huge amount of carbon goes into infrastructure and landscaping.
“There can be twice as much carbon involved in a new build,” Crowe says, with a much lower embodied carbon or “CO2 per metre squared” for the reuse of buildings. New buildings with the most basic timber frame can be around 319kg of CO2 per metre squared of embodied carbon, while a reused building can use as little as 55-200kg of CO2 per metre squared. It’s also difficult to calculate the carbon impact of land use change.
“Many historical buildings are in town centres, already serviced and well-connected,” he adds, a lot of embodied carbon involved in these new roads and pavements and in the services that connect to the new developments, which is “generally paid for by the taxpayer and through development levies.”
There is also an “urgency to this situation,” as 37%-40% of our emissions are from construction.
Despite protests that older buildings might be cold or drafty or damp, “if you restore the building fabric to function as originally intended, for example in terms of managing moisture and heat loss, the benefits for human comfort can be significant.”
We underestimate the performance of traditional walls, Crowe adds, citing research on brick walls by his colleagues: they can work well in terms of thermal conductivity and controlling the movement of moisture in the building. Viable nighttime solutions like blinds, shutters, and curtains can also reduce heat loss through windows by about 42%.
Maintenance is crucial and so, too, is water management. “Most climate change impacts relate to rainfall intensity – the amount of rainfall happening within a certain area and time,” Crowe says. “If your gutters and downpipes are not working, that is where major problems come in for historical buildings.” Letting water into the fabric of your building, “immediately compromises the performance of the building,” he explains. “If you have damp coming up from the floor or in through the wall, heat loss will increase dramatically.”
People often think it’s difficult to bring buildings up to high standards and regulations, but Crowe cites the EU’s concept of “sufficiency,” a not-impossible goal.
“People say I wouldn’t touch an old building,” Crowe says, “but you constantly have to be vigilant, even with new buildings, which come with a whole other list of challenges.” For historical buildings, “if the walls haven’t been tampered with, they can be extremely comfortable buildings to live in.”
It’s also about finding what’s available, underuse being a huge problem in Ireland, including vacant buildings and their backlands, along with a lack of means for knowing where vacancies are.
“A lot of the buildings that people would be interested in renovating just aren’t available,” he says, what’s on offer being, essentially, what developers have found sell – those sprawling estates. Crowe often hears people say they’d love to live in the town centre but there is limited choice and it’s lots of work, expense, and risk. Indeed, retrofitting building-by-building is not ideal.
COLLABORATION
While urban transformation is possible, “it isn’t possible with our funding structure policy and the programmes in this country,” unlike, for example, France or Scotland, who “have better mechanisms, resources, and programmes.”
“The Scots have often led the way in the reuse and renovation of buildings,” he says. “They have inherited the most extraordinary architectural heritage, often made of more robust materials, and have been at the forefront of building conservation, renewables, retrofitting, bringing those buildings back and appreciating and respecting them.”
While Irish towns have “beautiful buildings, often heavily disguised,” we haven’t had investment in social and physical infrastructure. Building-by-building grants puts the onus on private individuals who are the most unqualified and vulnerable, Crowe says. “It would solve a lot of problems if we did it in a collaborative manner,” leading to his second main point: the importance of community resilience, the urgency not just to do with climate change but social cohesion.
“If we don’t have functioning communities, we’re not going to be able to face the disturbances, like floods and extreme weather. Functioning communities help us respond to these disturbances.”
Community resilience is made, in part, with an attachment to place and to historical buildings, which often relates to heritage. People are bonded to buildings and places, Crowe explains, which can be powerful; they “will work to preserve that place, recognising that architectural and urban heritage is key to community resilience.”
Imagination is also key. “We can learn a lot from heritage buildings, including how to design, let water flow, create cool courtyards, keep the heat in. They are also a repository of values and different ways of living,” he adds, and “different ways of living together, different solutions.”
There has been success in Ireland, including Castleblayney, in County Monaghan, where the castle gate lodges were restored, one becoming a much-used library. In Westport, County Mayo, the former town architect Simon Wall “slowly but surely had a vision for the town and got investment,” he says. “It wasn’t easy, it’s a beautiful old estate town, but it is totally possible, requiring investment at scale and vision and commitment over time, not starting and stopping.”
“The town centre is suddenly an uplifting experience,” Crowe adds. “Towns can provide high-quality environments for sustainable communities. Reusing buildings can be part of this, giving a sense of pride of place, a sense of belonging.”
