On the whole, the development and planning process has not had great success in making and managing urban places in accordance with the principles of flexibility and sustainability outlined above. Our research indicates that the principal barriers arise from:
- The planning process.
- Different approaches to development
- Construction materials and systems.
The planning process
Balancing priorities and viability
The “nuts and bolts” of the planning process and development control can hamper the delivery of developments that enable New Urban Mobility.
The UK planning system requires contributions to infrastructure to be negotiated on a site-by-site basis. Balancing policy requirements at a local level while not impacting viability, in line with the National Planning Policy Framework, means that trade-offs are inevitable. For example, the amount of green space, the number of units, rights to daylight, and provision of community facilities could all be in tension with each other. Considerations that affect transport and mobility are no exception. For example: creating cycle parking or doorways that can accommodate e-cargo bikes will have space implications – and will therefore require balancing against other policy goals.
Relative policy and political priorities become important here. The overriding pressure to meet annual housing targets could squeeze provision for New Urban Mobility. The ability to deliver both depends on the capacity of planning departments, but also on political will and leadership. This can in turn reflect local attitudes towards mobility. Deep-seated cultural attachments to car ownership, electoral concerns of politicians and uncertainty about local public transport improvements all combine to mitigate against concerted action on sustainable transport. During our research, we have heard of developments providing the maximum parking spaces as a default in order to “get through planning”, rather than pushing for more ambitious targets.
Professional specialisms, inputs and standards
Planners’ and politicians’ ability to consider transport assessments and advocate for more sustainable options can be limited by professional specialisms. In addition
to a traditional disciplinary split between “Transport” and “Planning”, research has identified that where planning departments have in-house transport specialists to support the development management process, they typically come from a traffic and highways background. This means they can exhibit a bias towards traffic flow
considerations and may lack knowledge of other sustainability options. 28
However, without advisors to understand and advocate for sustainable options, their adoption is often limited. Similarly, having detailed input from operators on the cost of different sustainable transport interventions, sufficiently early in the planning process, could help ensure they are factored into deliberations. However, research has shown that this frequently fails to occur, and when it does, it can come too late in the process to be meaningful. 28
Many interviewees also expressed concern about whether the standards specified for “adopted” local authority roads were compatible with innovative approaches such as “FlexKerb” or “shared space” approaches to street design. A senior planning officer told us:
“Most people who work in highways in local authorities know about roads, that’s their background. They know about how to serve private motor vehicles, so the culture is more about sustaining flows of traffic, rather than evolving and changing our transport culture.”
Assumptions and predictions
One of the fundamental tasks of planning for mobility in new developments is the transport assessment process. Developers are required to plan for the amount of movement generated by the development. This involves attempting to model the new number of trips and their modal split. Typically, models use standardised assumptions about the mode share and number of trips generated for each type of
development, which are supplemented or adjusted to more accurately reflect local conditions.
However, these assumptions can be based on site surveys done several years ago, and as such will not reflect any recent changes or innovations in mobility, let alone future policy aspirations. In theory, professional judgement can rectify the problem, but this can also be based on outdated assumptions and analysis.
It is possible to obtain more accurate and upto-date assessments of current trends in mobility by commissioning bespoke surveys. But this is expensive, and therefore less likely to be developers’ first choice. Even where metrics for determining transport provision at a site are accurate and established – as PTAL is – our research participants suggested that the metric itself may be flawed, as it demonstrates a general level of public transport accessibility rather than an indication of where people will likely travel to and from.
Similarly, for large sites subject to multiple planning applications, initial transport assessments can become dated even over the course of the build-out. For instance, at Barking Riverside, a development site of citywide importance, planning permissions are being granted based on transport assumptions and modelling from 2004. 30
With limited resources and skills, it can be hard for local planning authorities to push for better evidence and to interrogate the assessments provided. Spending on planning and development services across local authorities in London has been reduced by just under 50 per cent in the period 2010-2018. 31 Reductions in budgets are impacting staff retention, experience, quality and departmental capacity. 32 Undoubtedly this presents a challenge for planning departments wishing to create and shape high-quality places.
Survey evidence from borough planning departments in London illustrates how this is playing out on the ground. While development management is still relatively
well resourced, planning policy, transport, parks, open space and public realm are all underserved, with some specialisms like public realm having shrunk by 75 per cent on average per department in recent years. 33 The level of capacity is not aligned with the levels of growth targeted for each borough, and a number of authorities have no in-house expertise in landscape architecture, public realm or development economics.
Development and management
Monitoring post-occupancy needs and changes
Good buildings can respond to changing circumstances: what is needed today may be redundant in the future, and what is needed in future may be unknown today. For instance, if there were improvements to local public transport provision several years after completion of a new development, this could allow for removal of car parking spaces. On-street car parking could be transformed into alternative amenity uses, such as cycle parking, parklets, or sustainable urban drainage systems. Similarly, basement and podium parking – if built to appropriate specifications – could be repurposed for leisure or commercial uses, which could then provide an income stream.
However, this process of evolution requires a mechanism for monitoring and responding to change. Typically, alongside transport plans for movement of people, planning applications for mixed-use developments require a servicing strategy to set out how movement of goods onto a site can be as efficient and sustainable as possible. In theory, these documents should be live plans that respond to changes in service provision and citizen behaviour. But in practice, monitoring and updating seems limited. At present, there is no regulatory requirement for landowners and managers to review the way that their developments are operating. This limits scope for ensuring adaptation and retrofitting in future. Without targeted incentives or mechanisms to guarantee it, future-proofing becomes dependent on the good will, or enlightened self-interest, of landowners.
Short-termism and absenteeism
Who owns, develops and manages new developments can impact on how well equipped they are to adapt to New Urban Mobility. The economics of different development models, the specialisms of different developers, the different interests in management of the land and the tenant mix will all have an impact.
Developers building for sale may not be interested in sustainable infrastructure that could require more hands-on management, or which is not yet “standard” and thus may not be popular with customers. For example, having flexible loading bays needs both a well-managed delivery and servicing strategy, as well as careful treatment of materials. Implementing such a plan might load costs onto the developer, as well as potentially limiting the range of potential occupiers/buyers, so this is unlikely to be considered unless stipulated as a planning condition.
In the absence of a long-term view or interest in a development, the same kind of business model might also mean less attention is paid to “place value”. 34
“We know the value of a river view, because we’ve been able to compare sales for 25 years. But we don’t know the value of an ethical property.”
Analyses of the relationship between property values and urban design demonstrate strong links between mixed-use, walkable, permeable neighbourhoods that are not dominated by cars and have good access to public transport, and increased property values. 35 This is in addition to wider social benefits such as reduced air pollution, lower incidence of obesity and asthma, and enhanced quality of life. 36
The other side of this equation can be a distant landlord or operator. Hands-off or inaccessible management can restrict how well developments are able to adapt to meet new mobility requirements. We heard examples of property managers being unable and unwilling to make changes to materials in response to fire safety concerns. In the words of an interviewee: “If some landowners won’t even do that, how can we hope for them to make other, less urgent changes?” A distant landlord with a hands-off business model is unlikely to enable adaption to New Urban Mobility.
Construction materials and systems
Building in permanence
The essence of adaptability is leaving enough “wiggle room” to accommodate change. This applies at all scales of construction – from the strategic level down to discrete components. Our cities are full of instances where this has failed in the past. Building inner-city roads to prioritise cars is the classic example – creating heavy concrete infrastructure that dominates its surroundings and is expensive and difficult to undo.
The same applies for building systems for dwellings. The problem can be purely practical – for example, having services too deeply embedded to change easily, or having structural components that do not allow for internal reconfigurations. Adaptable buildings allow for systems to change quickly – and especially those layers that have a shorter lifecycle than the shell and therefore will need to be changed. Table 3, adapted from theorist Stewart Brand, offers a conceptual framework for designing in adaptability.
Interviewees noted that adaptive design is often viewed unfavourably because it is conflated with a lack of precision.
“The latest technology becomes outdated very quickly and there’s always a requirement to go back and edit. But developers, architects and planners are often reluctant to say that what they’re doing isn’t right the first time as to them it sounds like an admission of failure […] we need to build in more tolerance.”
Head of Planning, London Borough
To put it simply, flexible design is not being widely adopted because the idea of adapting developments after they have been built is believed to reflect negatively on the architect/developer/builder, whose design lacks sufficient rigour to “get it right” the first time. This mindset needs to change.
There are also barriers to adaptation related to ownership of construction technologies, and their interoperability. Over-reliance on bespoke, patented technologies means that changing them involves relying on smaller numbers of suppliers. This could involve higher costs – or in the long run, the risk that the supplier is no longer operating. One research participant contrasted this situation with older materials such as timber stud and brick, which are argued to be much more “democratic” because the technologies can be easily adopted by different users. Centre for London has previously recommended a common design framework to enable standardisation and interoperability for new construction methods. 37