DENSITY Part 2: We're beginning to get the 'Eco' -- but what's Density?

Depends how it's measured; it doesn't have to mean taller

Michael Geller, Special to the Sun

Published: Thursday, February 28, 2008

'How much does your house weigh, madam?"

Buckminister Fuller, the famous architect who invented the geodesic dome, used to delight in asking this question at parties.

Of course, no one knew the answer, although people always knew how many storeys their homes had.

I was reminded of this by the EcoDensity debate taking place in our city.

This time, the issue is not weight, but rather density. Most of us do not know the density of our home or neighbourhood.

However, we generally assume that higher densities result in higher buildings. This is not necessarily the case.

Density, as a planning term, has a number of different meanings. It can be an expression of a building's size in relation to its lot, or the number of housing units or people in a particular area. It is not a measure of height.

In most Metro Vancouver municipalities, density is measured as the floor space ratio (FSR). To understand how it is calculated, let us look at an older home with 1,200 square feet on the upper floors, and an 800-square-foot, partly submerged basement.

If this 2,000-square-foot home occupies a 4,000-square-foot (33-by-120-foot) lot, it has an FSR of 0.5. The same house on a 6,000-square-foot (50-foot) lot has an FSR of 0.33. Newer single-family homes are typically built at the maximum permitted FSR of approximately 0.6.

A duplex or low-density townhouse zone has an FSR of 0.75. Apartment zones can vary significantly. Fairview Slopes was developed at 1.25; many new apartments are built at 1.45. Kerrisdale apartments are in the order of 1.7.

Other jurisdictions measure density in terms of UPA or units per acre.

In the Village of Anmore, the community is being developed at a density of 1 UPA. Most conventional single family neighbourhoods are in the order of 5 UPA, although more compact single-family neighbourhoods can be designed at up to 12 UPA. Apartment developments can be developed anywhere between 50 to 150 UPA, or more.

An apartment building with 100 small suites will likely place different demands on neighbourhood services than a similar size building with 40 larger suites.

For this reason, some jurisdictions measure density in terms of PPA or people per acre. A typical suburban development might accommodate 15 to 20 people per acre, while a dense urban area could easily accommodate 100 to 250.

Whether density is measured in terms of FSR, units per acre, or people per acre, higher density buildings are not necessarily higher buildings. We can double or triple the density of a neighbourhood without any significant increase in building height.

A major community concern is that additional density will require additional services and amenities. I agree with this concern.

However, by collecting Community Amenity Contributions from the builders of higher density developments, and demanding payments from developers undertaking rezonings, the city will have additional funds to pay for the upgrading and expansion of parks and community centres and the construction of new facilities.

Concerns about traffic and parking can be addressed through better transit, and creative off-site parking solutions.

Instead of building taller buildings, the focus should be on more compatible forms of densification, including rear-lane infill units; secondary suites in townhouses and apartments; duplexes, and more townhouses, apartments and mixed-use buildings along arterial roads.

The focus should also be on greener, more sustainable building designs that are more energy- and resource-efficient. While the development industry has some concerns with the city's proposed requirements, it agrees these new standards are not unreasonable given our collective desire to reduce our ecological footprint on the environment.

By building alternative forms of housing, we can create more affordable housing choices and livable neighbourhoods without altering the character of most single-family neighbourhood streets in Vancouver.

Over the next 20 months, city politicians and officials will have to move slowly, and test out these ideas on a "demonstration project basis" before any widespread application.

I hope we will give them the chance.

Michael Geller is an adjunct professor at the Centre for Sustainable Community Development at Simon Fraser University.

© The Vancouver Sun 2008