Is your community tearing down old buildings and building anew to gain energy efficiency and a “greener” environment?
If so, you are losing more than you’re gaining, according to a new way of thinking about old buildings that defines them as both far more energy efficient and “green” than presumed.
Nicola Spasoff, municipal liaison officer with the provincial government’s Historic Resources Branch, is author of a recent article appearing in the Municipal Leader that lays out the case that, when it comes to lessening a carbon footprint, and improving energy efficiency, an old building can be as good as new, if not better.
“There are a lot of people who think old buildings are ineffi-cient, and wasteful and drafty… and that’s just not actually the case,” says Spasoff.
Firstly, it’s important to remember that a huge amount of energy has already gone into any building’s construction in the first place, says Spasoff.
Known, as “embodied energy,” this is the calculable sum of energy required to extract raw resources, then refine, process, manufacture, transport and assemble them in the construction process. It also includes the emissions from pollution and waste associated with construction.
“It’s a piece of the equation that was left out until fairly recently,” says Spasoff, who points
to calculations done on a typical commercial building (4,650 square metres) to show its embodied energy equivalent of over 2.4 million litres of gasoline.
To tear a building down is the proverbial baby going out with the bathwater.
“As long as you keep that building, that energy hasn’t gone to waste,” she says. “It’s when you knock it down, all the energy that was used is gone.”
Then consider the vast amounts of additional energy required to erect new.
Many take the view that old buildings, particularly those built pre-Second World War, consume so much energy it makes sense to get rid of it, build new and incorporate new energy-efficient technologies.
But that doesn’t take into account the environmental impact of new buildings. Modern building materials, such as vinyl, can additionally be both energy intensive to produce and impossible to recycle or reuse, adding to the energy burden. Modern structures also have shorter lifespans which compounds the problem. Even the most energyeffi cient new buildings will basically need anywhere from 35 to 65 years to get real payback, when embodied energy is calculated into the equation, notes Spasoff.
“The vast majority of buildings going up now, and I’m talking about everything from housing to office buildings, are not intended to last longer than 25 to 40 years,” she said. “They will, themselves, not last as long as the buildings they are replacing.”
Moreover, there are inherent design features in older buildings absolutely worth saving. They were designed for times when cheap energy was not so available. People didn’t snap on lights and air conditioners at the turn of the century – there were no such things. So older buildings will have plentiful windows, and windows that open, cross-ventilate, and make use of natural ventilation and light.
“These were all things that were designed to help a building cool itself in a time when there wasn’t any other option,” notes Spasoff.
That’s unlike newer, modern structures that tend to have fewer windows and need the lights on all day, and heating and cooling systems running to keep steady temperatures.
It’s notable that cooling modern buildings can actually cost more and require higher use of energy than heating them.
Energy-saving features for heating, such as insulation and geothermal systems, and solar panels can also be retrofitted into old buildings too.
Older buildings are not necessarily better to heat but, with these sorts of upgrades, don’t tend to be worse either.
The new green building movement is keen to copy the features of old buildings for all these reasons, but there’s more.
Modern structures also tend to be built away from downtowns, unlike the early urban design that clustered commercial buildings in downtown districts. Environmental Building News has calculated that employees travelling between home and work to a building like this consume almost one-third more energy than the building itself, Spasoff notes in Municipal Leader.
Again, older buildings reduce that impact by having benefited from inherently greener land use planning as well as building design. Those older buildings standing in city centres and rural main streets – much of them pre-Second World War construction, are now touted as highly desirable examples of densely built, walkable town centres with easy access to services. It’s an approach that’s been embraced by a design movement called New Urbanism, which is attempting to restore neighbourhoods and reduce the sprawl and peripheral development of more modern times.
To build on a new site usually also requires using up additional land – sometimes good farmland or natural habitat – not to mention the additional infrastructure such as roads and utilities.
Historic Resources Branch architect David Firman points to what the Town of Carberry is now doing as an example of a rural community that sees the multiple benefits of old-building preservation and restoration.
Carberry has created a one-of-a-kind Main Street Heritage Conservation District Project, annually setting aside $10,000 to provide non-repayable grants to local businesses for frontage upgrades for character downtown buildings.
In so doing, they’re not only preserving their cultural heritage, they’re creating an attractive downtown conducive to a healthier environment in which people will want to shop and visit, says Firman.
In other words, saving an old building may just help more rural communities get back to the future.
For many reasons, says Spasoff, “we’re going to be glad to have these buildings in the long term.”