Medium-density,
Ground-oriented |
|
|
Given its central location, the scarcity of land remaining for
development, and its desirability as a place to work and live, development
pressures on Burnaby will likely continue. Higher-intensity development
and redevelopment are potential strategies that will help Burnaby
succeed in meeting this future demand.
Demographers and planners suggest that changes in the region’s population
will have significant implications for the amount and type of housing
needed. Over the next twenty-five years the population of the metropolitan
Vancouver region is projected to increase by 58 percent, from a 1996
population of 2,098,900 to a 2021 population of 3,311,500.1
This implies an average annual population increase of 1.8 percent.
Accompanying population growth will be shifts in age structure and
household size. By the year 2021 over half the population will be
in the over-forty-five age group and household size will be smaller,
meaning an overall increase in the number of households. The goal
of local and regional policy is to provide housing at higher densities
while still allowing families to live in dwelling units that have
direct access to the public realm (i.e., ground-oriented housing).
In fact, the GVRD has concluded that over the next fifteen years,
about 70 percent of the additional dwelling units needed to accommodate
increased growth in the region will be ground-oriented.2
|
|
No longer just associated with the single-family detached
home, ground-oriented housing includes forms such as the duplex, fourplex,
townhouse, and row house. In its medium-density form, ground-oriented
housing is distinguished by having individual unit access at-grade,
in contrast to other types of medium-density housing (i.e., garden
apartments or condominium units) that, more commonly, have unit access
via a central entrance and/or interior hallway. Occurring at densities
ranging from approximately ten dwelling units per acre to thirty-five
dwelling units per acre, medium-density forms are gaining a larger
share of the market and represent as much as 25 percent of all ground-oriented
units.3 |
|
The most common high-density ground-oriented form
in our region, the typical townhouse development, features strata-titled
ownership 4 and, most often, has units
facing inward, towards car access and parking. Virtually unknown in
our region is an earlier form, the “free-hold” townhouse. In this
type, units open directly onto the street and parking usually occurs
in a rear lane. It is important to emphasize that this pattern, so
common in most of North America’s older cities, uses land efficiently,
allows outright home ownership, and eliminates the ambiguous “semi-public”
space typical of most new suburban townhouse developments.
Ground-oriented housing offers many of the benefits associated
with the single-family detached house — privacy, security, freedom
of ownership — in a higher density form. However, many have questioned
the capacity of the strata development form to foster a sense of
community and to reduce auto dependency. It has also been suggested
that the preponderance of this type of housing does not reflect
market preference but is, rather, the product of the present regulatory
environment, which through zoning by-laws and traffic engineering
standards (such as limiting the number of curb-cuts allowed into
a development parcel and setting minimum parking requirements) produces
auto-focused rather than people-focused communities. We asked the
design teams to provide suggestions for how this form of housing
could be improved.
As discussed in the introduction, design charrettes are an ideal
vehicle for resolving the conflict between contradictory policy
goals relating to landuse. For instance, increasing density may
make public transit a more viable option, reduce car use, and potentially
improve the street environment for pedestrians and cyclists. However,
this increased density may also have a negative effect on water
quality. A challenge faced by charrette participants was how to
increase choices in the marketplace for ground-oriented housing
while still meeting other sustainability goals. The solutions provided
were simple and compelling, and they point towards the need to reconsider
our unsustainable regulatory practices.
The charrette proposals discussed below all conform to the Brentwood
Town Centre Development Plan, which calls for the accommodation
of 9,300 residential units on approximately 200 acres, resulting
in a residential density of about thirty-two units per acre on average.
These units would be supplied in an “expanded range of housing choices,”
including medium- and high-density multi-unit developments and medium-density
ground-oriented units. Approximately half of these units would be
high density, and half would be medium density. No zones allowing
single-family detached housing are proposed, although the surrounding
area is dominated by this type.5
This local area plan provided charrette designers with a basic
planning framework for the site; however, it left many important
urban design and community design questions unanswered. For example,
in what proportion, and in what form, should high- and medium-density
housing be allocated in order to achieve the best results? The charrette
proposals responded to such questions by incorporating housing and
community uses within a tightly woven grid of streets, pathways,
and open-space links, resulting in more sociable and ecologically
sensitive communities.
The existing pattern of development on the site has been influenced
by its early subdivision into an enlarged gridiron pattern (Figure
1). This enlarged grid has led to a development pattern in which
individual parcels are often larger than the standard 300-by-600
foot block size apparent in the surrounding districts to the northeast
and west. Redevelopment, if present trends hold, will most likely
occur on a parcel by parcel basis. These block sizes are too large
to allow high-density ground-oriented development in such a way
that would enable all dwellings to front onto a public street. Much
thinner block sizes are required. The City of New York, for example,
achieves its high densities while still adhering to the ground-oriented
townhouse pattern by having very thin blocks (close to 200 feet
wide).
There are only two possible outcomes for the Brentwood site, given
its large block size: either the City of Burnaby requires developers
to break down development parcels into smaller block sizes and cede
certain streets to municipal responsibility, or Burnaby accepts
the emergence of “gated communities” (which would be the inevitable
outcome of developing these super block parcels “as-is”).
It is important to distinguish between the nature of public and
private streets, as they each give rise to a different set of physical
circumstances. New medium-density developments typically rely on
a network of internal (essentially private) streets for circulation.
It is speculated that this is partly due to reluctance on the part
of municipalities to assume additional responsibility for public
street infrastructure and maintenance, and partly due to concern
for reducing conflict while maximizing traffic efficiency on arterials.
Even where developers are permitted to include public street dedications
as part of a development, existing policies that restrict access
onto arterials typically take precedence. The inevitable consequence
of this is the creation of large “super block” units surrounded
by arterial streets. The location and access of on-street parking
is also an important factor. The absence of parking on many public
streets means that residents and their visitors must always access
units from an interior roadway system. This affects the way that
the fronts of units function and, ultimately, the way in which the
street functions as a public place. These problems are addressed
in the examples below, where the site’s existing block pattern is
broken down into smaller units.
|
|
Charrette Solutions
In Example 1, the site’s existing coarse street pattern is replaced
with the finer-grained, 300-by-600 foot grid, resulting in smaller,
more regular block sizes and creating a more interwoven network of
streets (see Example 1 and 2). By using more — rather than fewer —
streets, all ground-oriented dwellings can exit onto a public street,
thereby clarifying the relationship between public space and private
space and enriching community life.
In another scenario, proposed by Team Four (Example 2), more streets
have been added and block sizes have been reduced in order to promote
diversity, flexibility, better circulation, and greater numbers of
people on the street.
Team Four also proposed to narrow the streets to make them richer
places for pedestrians and bikes while forcing traffic to slow down
(Exalmple 3). The fine grain interconnected street pattern guarantees
that each trip to the store or to the bus is via the shortest possible
route, thus reducing the necessity to resort to a car for even one’s
most basic needs.
|
|
Example 4 and 5, from Team One’s plan, shows how the
finer-grain grid, as a living, working component of the neighbourhood,
provides opportunities for allotment gardens, composting, and rainwater
storage. Each of the working greens is connected, at mid-block, to
the larger neighbourhood system by a series of green links. These
links connect (northward) to commercial and transit nodes along Lougheed
Highway and Willingdon Avenue and (southward) to the Still Creek basin.
Within the higher-density residential core, the central green becomes
an urban open space (see Example 6). |
|
Priority for vehicles is lessened in a village street
pattern, in which buildings are closely spaced and front directly
onto streets and sidewalks. Using this pattern, residential areas
can be intensified by allowing zero lot lines and by using party walls
on fee simple parcels as narrow as twenty feet (see Examples 7 and
8). This type of development supports a mix of incomes and household
sizes. A 2.5-storey unit on a parcel as narrow as twenty feet could
accommodate up to 1,500 square feet of interior space, with additional
floor space available in the “attic floor” above and in the full basement
below. Basement suites can be included and may have their own private
access to the public sidewalk.
In many of the Team proposals, occasional residential towers, with
at-grade commercial uses, provide continuous streetfronts along
the core streets; and more medium-density forms (such as stacked
townhouses and row houses) provide the necessary transition between
the high-amenity core and low-density fringes. Built at a scale
of 3.5 to 4-storeys, all units front onto (and are accessed from)
the street. A type of stacked courtyard housing, similar to that
found in many European cities, is suggested as an appropriate interface
between the high-amenity urban core and the surrounding lower-density
neighbourhoods. In this type of housing, the interior of the block
becomes a common lane space, providing residents with semi-private
open space (Example 9).
Conclusion
One of the objectives of this charrette, as stated in the introduction,
was “to show how sustainable design imperatives are influenced and/or
impeded by typical community and subdivision and site and traffic
engineering regulations.” Charrette designers understood how seemingly
reasonable and individual development requirements often lead, when
combined, to unsustainable and inhospitable communities. Their designs
suggest that there are smarter, greener, cheaper, and more livable
ways of designing our communities.
This exploration of charrette designs has demonstrated the economy,
equity, and ecological integrity of a fundamentally different approach
to sustainable urban design. Underpinninng this approach are several
basic principles for building viable communities. These include:
the integration of various housing types and tenures; ground-orientation
of units where possible; a mix of uses; and walkable connections
to neighbourhood destinations. While this approach is different,
it nonetheless has many precedents. This traditional urban form,
updated for enhanced efficiency and ecological performance, is a
proven neighbourhood pattern that is worthy of rediscovery.
next page
|
|
Notes
1 David Baxter, Homes in Metropolitan
Vancouver’s future: Housing Demand by Structure Type, 1996 to 2021
(Vancouver, BC: Urban Futures Institute, 1998).
2 Greater Vancouver Regional District,
The Livable Region Strategic Plan: Managing Greater Vancouver’s
Growth (Vancouver, BC: Greater Vancouver Regional District, 1993),
17.
3 Ibid., 11; Greater Vancouver Regional
District - Housing Task Group and Strategic Planning, Examples of
Ground-Oriented, Medium-Density Housing Projects in Vancouver (Vancouver,
BC: Greater Vancouver Regional District, 1996), 1.
4 Strata-titled ownership, typically seen
in attached-unit housing, restricts the outright ownership of an
attached dwelling to the built structure of the unit. The land under
and around the unit is owned collectively.
5 City of Burnaby, Brentwood Town Centre
Development Plan (Burnaby, BC: City of Burnaby Planning and Building
Department, 1996), 14.
|
|