Calgarians should think carefully before adding so-called hostile architecture to their city, a design specialist from Switzerland says.

The trend is seeping into urban design, from putting armrests in the middle of benches to prevent people from sleeping there to putting barriers on railings to deter skateboaders.

"We stop simply arguing for differences in public space," Selena Savic, an "unpleasant design" specialist and architect, told the Calgary Eyeopener on Monday. "We start solving all these potential conflicts of interest by excluding people and segregating."

Savic is the co-author of the book, Unpleasant Design. She recently toured Calgary looking at the various ways design makes this an unwelcoming modern city.

Under bridges in Calgary, large river stones are laid down to prevent people from sleeping there. C-Train stations have small pyramids on window sills to prevent people from sitting. Metal spikes keep pigeons away and garage bins are secured to keep bears out.

'Very strict' architecture

Most unpleasant or hostile design techniques are meant to make areas more pleasant to enjoy for their intended purpose — and are being sneaked into urban design without much public discussion, she said.

The elements do what they're intended to do quite well.

"As soon as architecture becomes very strict, it becomes kind of more successful in kind of navigating people, navigating use, but it becomes less adaptable to people's needs," Savic said. "I think it's a problem. People kind of need to be able to appropriate the space."

Two trees in an affluent Bristol neighbourhood have been lined with spikes to keep birds away. (Anna Francis/Twitter)

She gives the example of openly designed squares in Italy, which people freely use for a variety of purposes. The public space changes based on how members of the public would like to use it, she said.

Here in Calgary, they're often added by private developers or citizens improving their property. That can be a problem, as well, because the design elements are inconsistently applied. So, for instance, if there are spikes deterring pigeons from a popular hangout spot, those pigeons — and their droppings — will move to a new perch.

"The problem is that unpleasant design is always somehow beneficial," Savic said. "It reduces maintenance costs for many objects but it becomes extremely problematic when we start treating people like that."

Decorative objects, such as posts, rivets and fences, can be found along Moncton streets. They are designed to stop people from sitting on windowsills or lying on flowerbeds. (CBC)

Members of the public have agreed, and have protested such designs around the country as being discriminatory or disruptive to people in the area.

Here in Calgary, the Safeway grocery store in Kensington was called out online after putting rubber triangular bumps on top of a ledge to cut down on unwanted loitering.

A parkade in Vancouver had a device that emitted a high pitched squeal to deter mostly teenagers from hanging out at night. However, it also disturbed people living and walking in the area.

Concrete balls were installed in the exterior alcoves of retail stores in Vancouver where homeless people often camped overnight. (Dillon Hodgin/CBC)

In Moncton, spikes meant to stop homeless people from sleeping in public spaces garnered much public outcry.

This all offers an opportunity, Savic said, to have community members and designers think more strategically about how they design cities — and what can be done in public spaces.

"You can learn how easy it is to manipulate and control," Savic said. "Designers should go through this process of thinking unpleasant so they could also think pleasant — and not unintentionally think unpleasant."

Savic's visit to the city, which included a tour, talk and workshop, was organized by Esker Foundation in Calgary.

With files from Paul Karchut and the Calgary Eyeopener.

Calgary: The Road Ahead is CBC Calgary's special focus on our city as it passes through the crucible of the downturn: the challenges we face, and the possible solutions as we explore what kind of Calgary we want to create. Have an idea? Email us at calgarytheroadahead@cbc.ca.

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