An A-Z of Urban Design Concepts (and their misuse)

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“Active frontages” has become the ubiquitous catch cry of planners and urban designers. Activity centre structure plans are liberally festooned with stressed street edges. But is it a case of active frontages everywhere, nor any latte to drink? (Sorry, Sam.) The Activity Centre Design Guidelines define active frontages as “street frontages where there is an active visual engagement between those in the street and those on the ground floors of buildings. This quality is assisted where the front facade of buildings, including the main entrance, faces and open towards the street.” (Developers, please note, this is not the same as attractive frontages, such as art walls, green walls or display boxes.) Active frontages are often taken to mean continuous rows of highly-glazed shopfronts with frequent entries and cafes ‘spilling out’ into the street. But can every metre of street frontage be so animated?

Shops cannot activate side streets or rear lanes without compromising their primary frontage. Upper level accommodation, strongly encouraged in activity centres, needs car park entries, sub-stations and service cabinets with direct street access. Shops rely on heavy footfall for survival. In side or back streets, ‘secondary’ active frontages, such as the facades of offices, or leisure or community facilities, are a more realistic way of achieving visual engagement. A successful structure plan recognises that there can’t be continuous cafes from corner to corner.



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Visual bulk is an oft-raised impact of development. But unlike overshadowing or overlooking, it is an intangible impact which is difficult to measure. Acceptable levels of visual bulk vary from place to place. Are they also evolving, as we become used to bigger buildings? In essence, visual bulk is determined by two variables: how big and/or close the building is, and whether it is nice to look at. In a suburban context, where buildings are generally expected to be 1-2 storeys high and set back from all boundaries, even a 3-storey building is sometimes considered to have unreasonable visual bulk. Here, ResCode provides clear guidance. In high-rise areas, tall buildings are exactly what people expect to see, and visual bulk is measured by the space between towers rather than height. There, a spacing of 9-10m is generally preferred where it can be readily achieved.

Whether a building is nice to look at is highly subjective. However, modulation of the form, use of different materials and colours, and greening are generally thought to break up the mass of a building. Any consideration of visual bulk must also consider where the building will be seen from. If it is not within the primarily outlook of nearby, routinelyoccupied spaces, or if it will be heavily screened by landscaping, its impact is significantly reduced. Assessing visual bulk requires judgement of reasonable expectations, which vary from suburb to city, and which change over time as policy increasingly emphasises consolidation and bigger buildings become the norm.


The concept of neighbourhood character has turned Melbourne’s suburbs into an endless battleground pitching residents against developers, with planners stuck in the middle. Most of the arguments about character relate to density. People are familiar with the manifestations of their neighbourhood’s density – such as the vibrancy of Fitzroy or the greenness of Donvale – and they fear change to it. But we know that the density of our established residential areas cannot remain untouched if we are to accommodate the current explosion in housing demand without a commensurate expansion in Melbourne’s girth to obese levels. This isn’t all bad: a relatively small increase in density is enough to transform our middle and outer suburbs into more liveable and sustainable neighbourhoods, in which residents have easy access to shops and services by foot or bike. The question is, how can we minimise the impacts of densification on character? Urban design concepts include designing multi-unit buildings to present like a big house. But our assessment tools struggle to cope.

Setbacks are assessed by comparing dimensions with those of the neighbours. But character is perceived across a broader area than three properties. And can people perceive setbacks to the nearest millimetre, or is there a tolerance that is imperceptible? Height is measured in the number of floors. But is the visual presence of the building generated by its massing and landscaping not more relevant? The impact of development on the surrounding character can only be assessed by a comprehensive understanding of how it will appear from all vantage points. The recent emergence of photomontages is a valuable aid to this process. Building details, such as roof forms, materials and styles, can also be the cause of character arguments. But these elements are rarely so consistent that variation would constitute a fatal blow. Personal taste is a more likely root of these debates. The contextual use of contemporary building elements is an appropriate way to update character over time.


Density is a key measure for urban designers. But could we make better use of it in our planning controls? The intensity of activity in the public realm and the level of support for local businesses and services are largely driven by density. Urban design nirvana is sufficient density to support day-to-day needs within a comfortable walk of every home, with pockets of greater density to offer the choice of a more vibrant experience. Density can take many different forms. Traditional urbanism generated by low-rise but attached buildings and Corbusian towers set in parkland have surprisingly similar densities. Consequently, while minimum densities are a useful way of ensuring the creation of walkable neighbourhoods, the use of maximum plot ratios is a dubious device for controlling built form outcomes.

In NSW, built form is controlled by height limits and other measures. However, floor space ratios (FSRs) are also used to provide for equitable development outcomes within a precinct and to give a clear indication of the value of land to prospective purchasers. Would a similar tool reduce the speculative property purchases that lead to pitched battles over discretionary built form controls in Melbourne? Or would it unreasonably limit the development potential of sites with unusual circumstances?


It is hardly surprising that the first wave of innerurban renewal plucked most of the low-hanging fruit of large sites. Developers are now turning to the smaller sites, which are less able to accommodate the sort of generous setback possible with larger projects. How does this affect the future development of neighbouring properties? The Guidelines for Higher Density Residential Development contain the objective “To ensure areas can develop with an equitable access to outlook and sunlight” and a corresponding design suggestion to “consider the possible future development of adjoining sites and allow, as best as possible, or an equitable spread of development potential throughout the area”. i.e. development should not unfairly reduce the development potential of an adjoining property. The question is, what is fair? A rule of thumb has emerged from a series of VCAT decisions that residential development should be set back 4.5m from a common boundary with an adjoining development site. This is based on the ResCode principle that a 9m separation is enough to avoid unreasonable overlooking, and that the separation should be shared equally. Although the ‘inter-visibility’ resulting from lesser setbacks can be addressed by screening, this affects access to daylight, sunlight and outlook. Balconies are typically allowed to project into this separation because they aren’t expected to be private.

But a 4.5m setback on both sides is unachievable on properties 25m wide or less. So, if we are to avoid wasting land in well-serviced locations, we need to develop more sophisticated design solutions and rules. Fortunately, rules of thumb are made to be varied. Lesser (even zero) setbacks can be justified where there are no apartments with a primary outlook towards that boundary. Or where the adjoining property is substantially larger and can more easily accommodate side setbacks. Or where neighbouring properties are unlikely to be redeveloped (e.g. because they are strata-titled). The impact of a proposed development on its neighbours’ potential can only be fairly answered by understanding the likelihood of those properties being redeveloped and exploring whether a reasonable development configuration remains possible. The ‘4.5m rule’ is only the starting point for one design solution.


Designing residential frontages involves a delicate balancing act. They must not only provide reasonable amenity and privacy for residents, but good urban design also requires that they contribute to the safety and visual interest of the street. How can residential design allow occupants to surveil the street but prevent passing pedestrians from looking into private living rooms and open spaces? This is easily achieved in conventional housing by locating the main living spaces (indoor and outdoor) at the rear of the block and using a generous landscaped setback to provide privacy for front rooms. But apartment buildings typically have small setbacks and incorporate dwellings whose only aspect is towards the street.

The simple way to ensure privacy for ground level apartments and their terraces is a high front fence. But this creates a poor public realm. The optimum solution is a slightly raised ground floor level including a raised terrace. The difference in level combined with an impermeable balustrade is enough to provide privacy for ‘ground level’ apartments, while also allowing occupants to look into the street.


‘Gated communities’ are bad. The Safer Design Guidelines tells us so. But as with all doctrines, if the basis for it is misunderstood, an irrational fear of gated communities can lead to a worse outcome. Gated communities draw an almost visceral reaction from planners, because they imply exclusivity, which offends the intrinsic egalitarian basis of planning. Social planners promote mixed communities to foster tolerance and inclusiveness. There is another reason to discourage gated communities: they reduce permeability. Permeability is the ease with which people can pass through an area, whether by foot, bike, car or bus. The need to divert around large, impenetrable precincts creates longer and less legible journeys.

Scale is a key factor in both these concerns. Developments that occupy a single street-block may exhibit elements of a gated community (such as an open space at their centre only accessible by residents) but they do no harm. Their inhabitants cannot avoid interacting with the broader community. Walking around them to get to the other side is no different to walking through any gridded street network. On the other hand, requiring public pedestrian links through developments of such modest scale can do more harm than good. It can be difficult for development to address both street frontages and an internal link, leading to compromised safety in one space or the other. As always, the lesson (not learning, please!) is to analyse the specific impacts of a proposal and potential changes to it, rather than falling back on dogma.


‘Human scale’ is an oft-quoted but nebulous urban design term. It is regularly put forward as a reason to limit building height. But what is human scale and why is it important? In Melbourne, human scale is often suggested to mean 2-3 storeys. But the Southbank Structure Plan claims that a 30-40m street wall delivers ‘human scale’ in the central city. Can they both be right? And what do either have to do with the scale of a human? Perhaps the answer is that it is not about our height, but our field of vision. Is human scale a quality of that part of a building which can be comfortably viewed by a passing pedestrian without craning their neck? A building that has human scale may be one designed to offer a pedestrian-paced level of visual interest within this field of view – what Jan Gehl refers to as “3-miles-an-hour architecture”, in contrast with the substantially coarser ‘grain’ of visual interest perceivable from a car.

Test this out. Next time you’re in one of Melbourne’s traditional mainstreet centres, look across the street and see how much building you can see without craning your neck. The answer is that for 20m wide streets (eg. Chapel Street), the human eye can easily make out facade details for the height of a Victorian 2-storey building. Beyond that it becomes blurred peripheral vision. For 30m wide streets, greater height can obviously be seen, possibly explaining the taller sense of ‘human scale’ in the central city. So we prefer ‘human scaled’ buildings because they provide visual interest within our field of view. Perhaps this is a reaction against decoration-less Modernist architecture. In any event, it doesn’t preclude buildings having taller elements. It simply relieves them of the need to have that level of visual richness. The practical translation of this is an articulated podium façade, and a simpler upper-level form – not a height limit. Discuss.


The word “integration” is strewn liberally throughout our planning schemes. ResCode calls for development to be integrated with the street. (See “Frontages (residential)”, in the August 2012 Planning News.) State policy exhorts us to integrate land use planning, urban design and transport planning, and encourages us to design activity centres that integrate housing, employment, shopping, recreation and community services. ResCode wants schools integrated with the neighbourhood and community facilities; the built environment to provide an integrated layout, built form and urban landscape; and subdivision to integrate with the surrounding urban environment.

Integration means homes and offices above shops, or on secondary streets that lead directly to the mainstreet. Not housing estates or business parks that adjoin centres but have independent street networks which rarely connect.

What does all this mean? In urban design terms, integration requires more than just collocation. It entails a positive relationship forged by sharing the same public realm, or at least direct visual and physical links through an inviting environment. Examples include development that fronts the street leading to a station, or lines its forecourt. Not the backs of buildings on the other side of the station car park.

Integrated schools are those bounded by residential or activity centre streets, not back fences. Integrated subdivisions have streets that provide relatively direct and legible routes from every home to key destinations such as schools, shops, parks and public transport. Not those which barricade residents from their activity centres through traffic-dominated ring roads. In essence, integration means being part of the same place, not just close by.


(I know, I know. She wasn’t a concept. But you try finding an urban design concept beginning with J!) Jacobs was an American (and later Canadian) writer and activist driven by inner urban issues. She gained prominence with the publication of “The Death and Life of Great American Cities” in 1961, which quickly became a seminal urban design text. Jacobs fought against the conventional wisdom of mid-twentieth century urban planning, which was focused on creating neatly ordered urban patterns characterised by segregated uses, ‘superblocks’ and ‘pavilion’ buildings set in open space. She championed traditional urban places that had developed organically, highlighting the value of density in generating vitality and the economic and social importance of diversity. The intricate order of real city neighbourhoods, rather than the simplified, ‘pretended order’ of planned places.

So, what is Jacobs’ legacy in urban design today? Tellingly, much of the old accepted wisdom has been replaced by the ideas she espoused: mixeduse and mixed communities, higher densities that support convenience, varied building ages, finegrain street networks, streets in which children can play, clearly-demarcated public and private realms, ‘eyes-on-the-street’, flexible and active-edged open spaces, and so on. But perhaps Jacobs’ greatest lesson is the importance of careful observation and analysis of the way urban places actually work, rather than focusing on their outward appearance. Before the book has even begun she urges us to “please look closely at real cities. While you are looking, you might as well also listen, linger, and think about what you see.” Every place is different. And cities continually evolve in response to changing social behaviour, technology, globalisation and so on. So while Jacobs’ principles are enduring, their application must always be tailored to the intricate order of the place, rather than one-size-fits-all design responses.


Kevin Lynch was a professor of urban planning at MIT and authored several books with a focus on urban form. The Urban Design Reader (Routledge, 2007) makes the arresting claim that The Image of the City (1960) is “the most widely read urban design book of all time”. (Quite how they know this is unclear.) In any event, Lynch can reliably be said to have developed one of the most influential theories about how people perceive cities. Lynch made a particular study of the way people recognise the structure of cities and organise that information into ‘mental maps’ to help them navigate their way around. He concluded that city form can be understood in terms of five elements: paths, edges, nodes, landmarks and districts. The use of these elements not only enhances a place’s legibility, but it also creates more memorable places to which people can develop a sense of belonging. The older parts of our cities have a high degree of legibility and local identity because of the diverse elements that have been either planned in or which have evolved over time: a wide range of street types, street patterns on different alignments creating distinctive nodes where they meet, varied building forms and assorted use-mixes. In contrast, many of our new suburbs tend towards a dull sameness – minimum width local streets everywhere punctuated only by broad arterial roads, uniform street grids, homogenous project homes only distinguished by their colour and nary a corner shop. Any attempt to vary the formula is value-engineered out in the interests of efficiency and the holy grail of affordable housing.

The result is monotonous suburbs that could be anywhere. (And questionable benefits in terms of affordability. Just because lots can be delivered at a slightly lower price doesn’t mean they’ll be sold at a discount.) Good urban design, like planning, involves balance. Has the balance in new suburbs swung too far towards alleged affordability and away from creating legible and memorable places?


Landmarks are structures that stand out from their surroundings due to their height, use, unusual design or position at the termination of key viewlines. They are one of the key elements of good urban design that help people understand and navigate around cities. So where should landmarks be created and what qualities should they have? Landmarks enhance legibility when they mark an important place in the city. This might be the heart of an activity centre, an important public function (such as a town hall) or a significant transport node (such as a railway station).

The degree to which a landmark stands out should reflect the importance of the place. While a cathedral warrants a sky-piercing spire, a local library can be marked merely by distinctive design. Landmarks by their nature have a greater visual impact on the community. This carries with it a responsibility for excellent design. (In contrast, while ‘infill’ buildings should meet minimum design standards, they need not be extraordinary.) Landmarks are an important element of good urban form. But their distinctiveness must be scaled relative to their importance and their design quality must match their visibility.


Melbourne’s first car-free mall opened in 1956 on Bell Street, near the Olympic Village. Malls proliferated in the 1970s and 80s, in an attempt to create more pedestrian-friendly shopping centres. However, traffic has since been reintroduced into many and others are struggling for survival. Why? A pedestrian-friendly environment is one factor in a centre’s attractiveness, and therefore its economic success. But it is not the only factor. Most people drive to shops, so convenient vehicle access and parking are also important. The value of handy parking increases after dark, when people are less comfortable walking down alleys to their car. Removing cars from a street diverts that traffic and associated parking to surrounding streets. When this is a main artery, it can result in a heavilytrafficked ring-road around the centre, repelling pedestrians. (Visited Ballarat recently?) However, traffic also has benefits. A flow of cars past shops generates ‘passing trade’– business resulting from potential patrons being reminded of those stores every day on their way to and from work – demonstrated by the prevalence of ‘traditional’ centres along main roads. And traffic enhances pedestrian safety in the evening, by providing ‘eyes on the street’ when most centres have little pedestrian activity.

This isn’t to suggest that pedestrian malls can’t work anywhere. CBDs and regional shopping centres can incorporate malls because their bigger range of shops and more distant higher-order competition is enough to attract customers. But most centres lack the competitive advantage to withstand the mauling of a mall. There is a middle ground. Acland Street in St Kilda is very pedestrian-friendly but still allows cars through. Its kerbside parking and car-borne passive surveillance is part of its success. Alternatively, streets can be closed to traffic during daytime business hours and open during evenings. Pedestrian malls have their place. But they rarely work in smaller centres. Instead, more creative approaches are needed to create pedestrianfriendly environments.


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Clause 56.03-1 seeks walkable neighbourhoods, where people can walk to activity centres, schools and community facilities, public open space and public transport. What is a walkable neighbourhood? Current dogma is that people will happily walk 400m (or about five minutes) to get somewhere. The distance people will walk is influenced by numerous factors, particularly how inviting the journey is and what the alternatives are. And it varies based on factors such as health (current and desired) and the weather. 400m is a kind of averaging out of all these factors. The difficulty comes when the catchments of the facilities we want people to walk to are considered. Primary schools have a catchment of around 3000 dwellings in Victoria. At typical contemporary residential densities of around 15 dwellings per hectare, this requires an area of about 200 hectares. Even without other uses, this represents an average distance from catchment centre to edge of approximately 800m (or a ten minute walk). Similarly, community hubs and any form of retail bigger than a corner shop require greater catchments than can be achieved within a 400m radius.

So, in order to achieve truly walkable neighbourhoods, we either need to stretch people’s willingness to walk well beyond five minutes, or increase residential densities well above 15 dwellings per hectare.


Overdevelopment is a legitimate term, referring to buildings that are too big for their site. Unfortunately, it has been devalued through its use by those wishing to object to a proposed development but unable to express why. The development capacity of a site from an urban design perspective is determined by careful analysis of a range of factors, including the desired amenity and character of the public realm, and the amenity and development potential of neighbouring properties. It cannot be defined in terms of height alone – it must be delineated in three dimensions. Many of the urban design-related implications of development for its surroundings are to do with how it appears to someone at ground level. This means that taller buildings can be acceptable if their upper levels are sufficiently set back to be hidden from view, or to form a minor part of the overall visual impression. If a building has an additional floor which cannot be seen from anywhere, how can it have a visual impact? It is critical to understand the effect of perspective. Simply put, the further away a building form is, the smaller it appears. For example, a 3-level podium has a much greater visual impression on someone at ground level than the same number of levels on top and set back from the edge of that podium. (This effect is true for an oblique view as well as a perpendicular view.) Large and landlocked sites offer an opportunity for taller forms at their core with an equivalent or lesser visual impact on the surroundings than much lower forms at the edge of the site.

Taller buildings can be more obvious in long views than from nearby. But this often adds interest to the skyline rather than detracting from amenity or character. So, next time you’re faced with a development proposal that is taller than its surroundings, consider how it will actually be seen from the adjoining public and private realms before reaching a conclusion about whether it represents an overdevelopment of its site from an urban design perspective.


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The term ‘placemaking’ has become so over-used in recent years that it has almost lost its meaning. But it is one of the most fundamental urban design concepts. Placemaking is quite simply the creation of memorable places. While connectivity, safety and sustainability are important aspects of urban design, its real ‘art’ is to simultaneously make them distinctive, enjoyable and meaningful. The best urban places have a quality that ensures they leave a long-lasting and positive impression in people’s minds, which attracts visitors and would-be inhabitants.

Placemaking can involve capitalising on an outstanding natural setting, building a distinctive environment or programming unique activities. The development of Melbourne’s Southbank and Docklands has created memorable places by exploiting its waterside settings. Melbourne’s boulevards, such as St Kilda Road, are widely renowned as memorable places. The success of Federation Square owes much to the continuous stream of events it hosts. Urban designers should be constantly vigilant against the scourge of formulaic plans. Placemaking should underpin any plan for a new urban place or improving an existing environment.


As our cities densify, and taller buildings become more common, design quality has become an increasingly important issue. Why is it important? How can it be guaranteed? And how can it be assessed? Lower, infill buildings have relatively limited impact on the visual quality of the environment, rarely being visible beyond their street-block. Taller buildings can be visible across a much broader area. This has a significant influence on the character and appeal of whole urban districts.

There is an emerging trend of planning permit conditions requiring the architect that prepared the application plans to be engaged for the duration of the project. This is an attempt to avoid a high quality design concept being poorly implemented, as developers seek to ‘dumb down’ the design to reduce cost. Design quality includes an appropriate response to the context and an internal layout that meets the ‘program’. However, the aesthetic success of a building is the most difficult to assess. To some extent, the beauty of a building is in the eye of the beholder. Architectural style is subjective. However, there are principles of good composition that lead to general agreement on good and bad buildings. An attractive building is one that has a clear and well resolved architectural concept. Typically, this involves a single compositional idea, rather than an elaborate concept, reinforced by an ‘elegant sufficiency’ of materials and finishes. As Mies van der Rohe pronounced, less is more. Design quality becomes more important with a building’s visibility. It is ensured by a clear and cost-effective architectural concept, rather than one that relies on expensive construction techniques or materials.


The desire to accommodate urban consolidation in characterful areas, such as traditional activity centres, has led to the concept of ‘visually recessive’ upper levels. The idea is that if additional levels are sufficiently recessive, they won’t unacceptably detract from valued streetscape character generated by lower forms. The difficulty arises with regulating and assessing recessiveness. How recessive does an upper form need to be? How can recessiveness be evaluated? The tendency in planning provisions is to rely on a minimum setback to enforce recessiveness. However, this is based on assumptions about the heights of the lower and upper forms. Given that height limits are typically discretionary maxima, there is considerable scope for buildings with a lower podium or greater overall height to thwart the desired recessiveness specified by minimum upper setbacks. An alternative way to regulate recessiveness is to limit the proportion of the building view that is occupied by the upper form. Upper forms can be made more recessive through a lightweight appearance, particularly where this is contrasted with a more ‘solid’ lower form. A lightweight appearance is created by a high proportion of openings such as windows or recessed balconies, and segmented rather than monolithic materials, such as metal or timber cladding.

Colour can also affect recessiveness. Both particularly light and particularly dark colours tend to draw the eye, whereas muted, mid-toned colours, such as grey, are less striking against the sky. Recessiveness is an important urban design tool. However, it cannot be measured simply by upper level setbacks. More sophisticated provisions and assessments are necessary.


The ‘street wall’ is the front façade of a building where it is built on or close to the street boundary. It is an important urban design element because it defines the public realm. Planning schemes often promote a 3-storey high street wall in activity centres. But is that always the best outcome? The height and detailed design of a street wall should respond to any valued built form character, including heritage fabric. In traditional activity centres, the character is often defined by 1-2 storey, narrow-fronted, Victorian, Edwardian or Inter-war buildings with parapet heights reaching approximately 10m. A typical contemporary 3-storey podium fits comfortably within a traditional 2-storey streetscape due to its more modest floor-to-floor and parapet heights. Dividing the façade into vertical modules further reflects the traditional fine-grain streetscape rhythm. Traditionally, bigger buildings such as banks and hotels were built on street corners. New corner development can reinforce this character through greater street wall heights.

But what about places where there is no valued character? Most streets can accommodate a street wall well above 3 storeys without feeling too enclosed or being uncomfortably overshadowed. This presents an opportunity to establish a more distinctive identity through stronger spatial definition – increased street wall heights can contribute to a more memorable sense of place. Ensuring the right street wall height and design in more ‘urban’ areas is a key urban design issue. Three storeys is often the best fit in traditional centres, but there are many circumstances where greater height may be appropriate.


Melbourne is experiencing a proliferation of towers. Increasingly, these are being built on smaller sites, placing them ever closer to neighbouring towers and heightening concern about tower separation. The Melbourne Planning Scheme seeks a 24m separation between taller towers. This is consistent with planning provisions elsewhere in Australia and overseas. But it precludes the development of narrow sites. How can smaller properties be developed while maintaining good internal and public realm amenity? Potential internal amenity impacts of lesser tower separation include access to sunlight and daylight, outlook and privacy. However, these are eliminated where the apartments (or offices) are oriented away from adjoining towers. Tower spacing also affects the sunlight, daylight and sense of enclosure of the surrounding public realm. But since narrower towers have lesser impacts, does this allow for narrower spacing? Alternatively, with careful planning, two or three narrow towers can combine to form a single form with the same effect as one broader tower.

Inevitably there will be situations where towers cannot be developed on narrower sites without having unacceptable amenity impacts or prejudicing the future development of adjoining properties. Does a transferrable development rights system offer an equitable way to manage this? There seems to be a consensus that a separation of around 20m is appropriate for taller and broader towers. However, there is also a need to identify creative ways of enabling the development of narrower sites to capitalise on land in well-serviced locations. Careful and coordinated design and innovative planning provisions may offer a solution.


New Urbanism is a movement to bring back traditional qualities of cities and towns that got left behind in the Modernist fervour and car-based urban development of the 20th Century. These qualities include: • • • • • • • •

Mixed use Diverse housing Walkable neighbourhoods Public transport orientation Sufficient density to support local services Purposeful (rather than left over) open spaces close to all homes Buildings that define and address the public realm Locally-relevant architecture and landscaping

There is little argument amongst urban designers about the merits of these qualities. Indeed, they were promoted by numerous commentators well before the formal advent of New Urbanism in the 1980s.

The real debate about New Urbanism is in its realisation. The extent to which some of the qualities of traditional urbanism can be achieved varies depending on the physical and economic context. However, the almost evangelical zeal with which the movement has been adopted by some risks the formulaic reproduction of preferred solutions without reference to context. The danger is that this will stall the project or lead to exactly the type of placelessness that the movement seeks to avoid. New Urbanism promotes essential qualities of successful urban places. However, the creation of these qualities cannot ignore the physical and economic context.


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Urban places benefit from interesting-looking buildings. However, buildings can also be too ‘busy’. What is the right balance? Is visual interest more important at lower or higher levels? Visual interest can be increased by varying the form of the building, the external materials and finishes, and the pattern of windows and balconies, and by adding architectural features such as projecting ‘frames’ and shading devices. The need for these measures depends on the prominence of the building. A small infill building should seek to fit into its setting rather than draw attention to itself. In this situation, a simple form with one primary wall material and, at most, one feature material is usually sufficient, and more variation is often too much. Larger buildings typically require more variation to avoid a bulky, overbearing appearance. A ‘finer grain’ of variation is needed at lower levels to provide visual interest and break up the scale of the building in close views. This can be achieved by subtle variations in form such as vertical indents, integrated architectural features such as sunshades or an irregular pattern of openings. Care should be taken not to introduce too many materials, colours or finishes, which can detract from the coherence of the overall architectural composition. Upper levels of taller buildings tend to be mainly seen in longer views. Therefore, a ‘coarser’ grain of variation is appropriate.

The best examples are sculptural tower profiles, often clad in a lightweight skin distinct from the base. The form should be allowed to ‘do the work’, rather than overworked facade articulation. Visual interest is an important consideration in designing and assessing buildings. However, a distinctive form combined with a limited palette of high quality materials and integrated features is usually more successful than a rash of applied elements. As is often the case, ‘less is more’.


Wayfinding is about working out where you are and how to get where you want to go. In an urban design context, it refers to the clues provided by the urban environment to help people navigate their way around. Signage is one method. But traditional directional signage is of limited help, particularly to the blind or vision impaired. Too much signage can also create unattractive environments. Contemporary urban wayfinding is about building a wider range of visual, audible and tactile cues into streetscapes and buildings. Urban design techniques to enhance wayfinding at a ‘macro’ scale include: •

A built form pattern and streetscape design that reflect the level of each street in the hierarchy – e.g. taller buildings and formal avenue planting on main roads Landmark buildings and memorable open spaces at key places in the movement network – e.g. towers at stations Building and streetscape design which contributes to a distinct character in each precinct – e.g. different forms of development or street tree species in each neighbourhood

These features help people create a ‘mental map’ of an area, which they can use to help navigate around it.

Innovative wayfinding techniques at a more ‘micro’ scale include: •

• • •

Location maps with 3D representations of key destinations and how long it will take to walk to them Tactile or embossed location maps, including raised lettering and braille Tactile paths Press-button or motion-activated audible signage

Good urban environments are those which are universally accessible and easy to navigate around. This requires a more sophisticated approach than the use of conventional signage.


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WAYFINDING


Memorable urban places are well defined spatially. Spatial definition is created by the height of buildings (or sometimes trees) relative to the width of the street or open space they address, and their continuity (or lack of gaps). It is often suggested that a building height to street width ratio of 1:1 provides an optimum level of spatial definition, or enclosure. But can lesser or greater degrees of enclosure also be acceptable?

But another quality of good urban places is diversity. The contrast between wide boulevards and narrow streets and lanes in central Melbourne is a key part of its attraction. The intense character of a street of skyscrapers has value as does the arcadian character of a wide, tree-lined suburban avenue. These differences help to create distinct place identities and contribute to the legibility of the city.

Spatial definition or sense of enclosure is one valued quality of a street or space. Its inverse, a sense of openness, is another. Solar access can be important too.

A street enclosure of 1:1 is a well-founded rule of thumb. However, it shouldn’t be used to preclude other characters.

A building height to street width ratio of 1:1 achieves a balance between spatial definition and a sense of openness. It also avoids overshadowing the southern side of an east-west street for more than half the year in Victoria. That makes for a good outcome.


Architectural style is a key feature of building design. After height, it is probably the aspect most commented upon by laypeople. But how much does it matter from an urban design or planning perspective? In our most consistent heritage streetscapes, a building with a distinctly different style can detract from the valued coherence of the environment. The same is true in new neighbourhoods built with a common architectural theme. However, it is rare that there is a single style which is sufficiently dominant that it ought to dictate the design of new development. Most of our streets are more eclectic when it comes to architectural style, featuring buildings from a range of eras. In this instance, is the question of which style to adopt simply a matter of personal taste?

Many planning schemes encourage contemporary design and discourage historical mimicry. This promotes architectural innovation and allows building technology and expression to evolve, rather than stagnate. However, current architectural fashion will eventually become dated just like any other style. In time, it will come to be just another contribution to the eclectic character of a mixed area. Architectural style is an important consideration in areas with a highly consistent character. Elsewhere, is there a strong reason to favour one style over another?


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A zero setback from the street is commonly sought in activity centres. Why? And are there circumstances where a setback is appropriate? Zero setbacks are often required because it forms a key element of the existing character. But there are other reasons too. They ensure a clear demarcation between the public realm and private land. In contrast, a landscaped setback in a commercial area can create an ambiguous space, neither used nor cared for by the public or building inhabitants. A zero setback also ensures a direct interface between the window and footpath. A strong visual connection between passing pedestrians and the goods and/or activities inside the adjacent premises (and spilling outside) contributes to the vitality and attraction of activity centres. Sometimes buildings are set back from the street boundary to enable the creation of a public plaza or forecourt. While this maintains a clear demarcation between the public and private domains, it detracts from the character of most centres and the proximity of pedestrians and shopfronts. The exception to this is corner locations, where pedestrians can cut across the space, remaining close to the building edges.

Smaller, partial setbacks can provide articulation to a façade and space to pause in front of a pedestrian entry. Where they take the form of shallow recesses (up to half a metre deep) within a façade that is otherwise built to the boundary, they are unlikely to detract from the character of a street or the connection between passing pedestrians and the inside of the building. Zero setbacks are preferred in activity centres for a number of important reasons. However, plazas on street corners and shallow façade articulations can make a positive contribution to amenity and character. That’s it for the A-Z of Urban Design! Thanks for all your support and feedback over the last year or so. Watch this space for a new urban design column coming soon …


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