City Structures 02 Determining Housing Densities City Structures 02 - 1 How Should Housing Densities be determined? A comparative analysis of Brisbane and Copenhagen Greg Bamford University of Queensland Email: g.bamford@uq.edu.au ABSTRACT Modern urban housing densities, actual or proposed, show enormous variation. 'Broadacre City', Frank Lloyd Wright's proposal from the early 1930s, for example, was several thousand times less dense than the Liverpool docks had been in the middle of the previous century. What housing densities should we aim for? The determinants of housing densities can be thought of as either internal or external to habitation. The former concern the space households acquire or are allocated to satisfy the functions or desires of habitation; the latter are those forces, external to habitation, which influence density, such as the provision of public transport, the profit seeking behavior of developers or government policy to slow urban spread. I begin with some brief reminders of how in the recent past when urban compaction theory or practice has been in the ascendancy (internal) considerations of habitation have not been given due weight. Is this the case again? I compare a sample of higher density housing types and schemes in Brisbane with Copenhagen, a denser city admired by compact city advocates. This comparison produces some surprising results about relative densities and should give us cause to think again about levels of amenity and the usefulness of external space in our higher density housing, whatever our beliefs about the need for such densities. INTRODUCTION: FROM THE LIVERPOOL DOCKS TO ‘BROADACRE CITY’ i Lionel Frost describes a crowded area in 1790 near the Liverpool Docks in which additional houses in the form of three storey back-to-back terraces (with cellars) were shoe-horned into the back yards of the existing terraces such that one half-acre lot carried as many as 130 houses. The population density of this area was then in excess of 4, 000 people per hectare (pph). ii With sub-letting and taking in lodgers through the first half of the 19th century, the density rose to an extraordinary 7, 067pph by 1851 (Frost 1991: 13-14). What would such a density be like? A Brisbane ‘Six-pack’ is a three storey building - six flats on the upper two floors and garages under at ground - on an 800m 2 lot. To match the density of 19th century Liverpool, almost 700 people would somehow need to be accommodated on this lot. Squeeze a second Six-pack onto this site and we would need to cram only 50 people into every flat with a couple of families camping out in each of the garages. Just 80 years later, the American architect Frank Lloyd Wright proposed ‘Broadacre City’, a city so dispersed - every citizen would have at least an acre of ground to tend - it would be “everywhere and nowhere” (Fishman 1982: 92, Frampton 1992: 190). Wright imagined that something like Broadacre City was inevitable, and to the extent that our cities have frayed so extensively at their edges they are surrounded by vast "peri-urban" or “ex-urban" zones (Hugo et al 1997), heavily reliant on the motor-vehicle, Wright was right. How shall we live then, in sunny Brisbane? iii Not for us, thankfully, the grim conditions of the 19 th century Liverpool docks, living at a density which would see the edge of Brisbane only a few kilometres from the centre of the city, roughly where Toowong, Breakfast Creek and Stones Corner are