Share:

Discarding the past

Smallwood calculated that saving the Wallis House (shown here) diverted the equivalent of 500,000 blue boxes of debris from entering landfill

Photo: Smallwood calculated that saving the Wallis House (shown here) diverted the equivalent of 500,000 blue boxes of debris from entering landfill

By

L.A. (Sandy) Smallwood

Buildings and architecture, Environment

Published Date: May 28, 2009

When an old building is torn down, we lose more than just the structure. We lose a bit of our past.

The foundation walls and roof of every building represent manufactured products that used resources harvested from our environment. When a building is demolished, these products are often sent to landfill. But with many pre-1960s buildings, the materials they’re built with are far superior to those found in more recent structures. Older buildings often contain wood that came from old-growth forests – this wood is no longer available and, once it joins our landfill, is gone forever.

Older foundations were frequently constructed of hand-cut limestone, a process so labour-intensive that even the most expensive houses today can no longer afford to use it. The list goes on. These products (and the processes to make them) are largely too expensive and, in some cases, simply no longer available.

So, why do we throw our old buildings away? Why do we fill our dumpsters with irreplaceable materials? The reasons people cite are many:

  • Esthetic – architectural styles fall from fashion after 20 years
  • Economics – it is believed that it’s cheaper to demolish a building than to upgrade it to meet market and code demands
  • Functional obsolescence – purpose-built structures (e.g., churches) can be difficult to adapt for new uses
  • Building codes – it is believed, for example, that fire codes favour new buildings over old
  • Energy efficiency – the desire to have a so-called “green building”

Craftsmanship like this is often too expensive to reproduce today. Consequently, we’re losing these skills. (Shown here, the former residence of Sir Sandford Fleming – Winterholme – at 309-311 Daly Avenue, Ottawa.)

The last two issues on this list merit particular attention. Building codes are constantly changing. There is often a perception that a building that no longer conforms, as a result of a code change, is no longer safe. With respect to fire codes specifically, there is no doubt that fire safety is of critical concern. But are old buildings less safe than new ones?

According to a recent study, people had as little as three minutes to flee a fire under certain conditions – compared to 17 minutes in a similar 1975 test. Several reasons that could have caused this significant reduction – in particular, modern furnishings made of more synthetic materials, and the replacement of wood, heavy plaster and stone with plastics, drywall and other synthetic materials. In addition, the change in construction to the use of lightweight framing – particularly for roof construction – has led to roofs collapsing after approximately 23 minutes compared to 38 minutes experienced during 1985 tests. Based on this information, it would appear that more lives could be saved if codes instead concentrated on ensuring that building contents and new construction techniques/materials meet minimum fire-spread ratings, as these appear to play a far greater role in occupancy safety than the age of the structure.

Furthermore, a trend in recent years has been the pursuit of energy efficient buildings. This pursuit has had an unintentionally negative impact on many older structures. There is a perception that to create something green means we must build something new. The reality, however, supports the fact that – in many cases – older buildings offer more opportunities and can often out-perform new structures. A properly maintained solid masonry building that has benefited from a door depressurization test can be made as efficient as a new building. Just seal the leaks and add insulation. Similarly, properly maintained wood windows can last indefinitely. With new technology, it is now possible to add interior storm units to get around the annual chore of changing storm windows.

Restored wood-frame windows can provide superior R-value to more modern vinyl or aluminum replacements. (Shown here, the lobby of The Strathcona Apartments, 404 Laurier Avenue East, Ottawa.)

Restored wood-frame windows can provide superior R-value to more modern vinyl or aluminum replacements. (Shown here, the lobby of The Strathcona Apartments, 404 Laurier Avenue East, Ottawa.)

It should come as no surprise that wood remains a better insulator than either aluminum or vinyl. And yet, many new LEED-certified buildings are constructed using glass wall exterior cladding systems that normally provide an R-value of 3.5. Compared to an uninsulated masonry wall with an R-value of 7, it becomes clear that sealed glass wall systems that have a relatively short lifespan before the seals fail are not the way to go.

What can be done to change the mindset that relegates so many of our old buildings to landfill? Certainly, more work needs to be done to ensure that building codes recognize and give credit to the benefits provided by traditional construction methods and materials. All levels of government must also recognize the importance of saving existing structures through tax incentives.

The positive contribution made to the environment in saving heritage structures also speaks to the current economic incentives of governments worldwide. Environmental surcharges should also be levied on all development applications that include demolition – as well as providing credits in the permit process for all structures maintained and reused (as well as reusing building materials). Zoning bylaws need to be changed, too, to better protect existing structures instead of providing further incentive to demolish. Of course, our default position should be no demolition. Period. Instead of discarding our past.