The London Plan Tall Buildings & View Management Policies Suggestions for the Future

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1 The London Plan Tall Buildings & View Management Policies Suggestions for the Future Briefing Note from UDL Policy Symposium, 28th June 2016 Discussion Leads: Annemarie de Boom, Director, Studio Real Vinita Dhume, Associate, Levitt Bernstein John Hare, Director, Miller Hare Elliot Kemp, Senior Strategic Planner, GLA Attendees: 126 Esther Kurland, Director, UDL (Chair) Chris Twinn, Founder, Twinn Sustainability Innovation These notes are split into four sections: 1. What is the role of tall buildings in London? What can they offer us? How should we plan where they should, or should not go? 2. The microclimatic and resource use of tall building proposals 3. Tall buildings as a form of super, or hyper dense development, and what this means for users 4. The relationship between the management of cityscape and views and the location and shape of tall building proposals The aim of the debate, and these notes, is to provide ideas on how London Plan policies on the topic could evolve, based on an understanding of how current policies are working. At the end of the notes there is one suggestion for policy direction. It may not be the best one, certainly would not be the only option, but it is presented to help the conversation. 1. What is the role of tall buildings in London? What can they offer us? How should we plan where they should, or should not go? Before delving into the complexities of tall building planning policies, it is worth taking a step back and considering what the role of such structures should be for London. Is it about accommodating new homes and office floor-space in intensely used and active areas? Is it about pulling in investment and offering a product that is viable and attractive for developers? Is it about changing the appearance and character of London and so its perceived offer to the rest of the world? Without discussing these fundamental issues, it is hard to consider the details of individual policies. The current London Plans approach links tall buildings to the compact city approach, seeing them as a way of increasing density at highly accessible points. We were shown a map (see below) illustrating the general overlap of the CAZ and town centres (yellow), opportunity areas (grey outline), PTAL s 4-6 (orange) and tall buildings (black dots).

2 However the debate threw up the question of whether these denser, higher residential buildings were actually creating the type of homes London wants and needs. The economics of building taller buildings with its higher service charges may not necessarily optimise the housing opportunities available to working Londoners. The London Plan team might like to look at evidence at who is living in new tall residential developments, and how this might change in the future. Questions were also raised as to whether building tall was in fact the best way of using well serviced land, or whether other forms, such as mid rise blocks, offer a better solution. This debate has been ongoing for some time now, and the GLA may find their research on density helpful in informing the conversation. To optimise the use of midrise in delivering floor-space, a hard look at the standards that might be restricting this could be useful. It is probably that in some cases low to medium rise will be the best option, in others tall towers, and elsewhere a combination of both. If the purpose of tall buildings is about offering a development option that is attractive to certain developers, then a good hard look at whether this is sensible long term approach would be welcomed. It seems to some that the implementation of current policy, i.e. the grant of planning permissions, seems at odds with the actual wording of policies. It may be that pressure through the national planning system, a drive to pull out of the recession and other factors mean that in practice this objective is more active than it seems when reading the Plan. Finally, if we want tall buildings to alter the perception of our city, then that deserves a robust public and political debate. Once we are clear on what we want from tall buildings, the plan can consider where they should, or should not go and how this is to be determined. At the moment we have a combination of sieve analysis based mapping in some parts of London and a lineal link between identified areas for development and the use of tall buildings elsewhere. This has lead to a rather confusing approach in reality, with some using growth as a starting point and others protection of historic assets, views and townscape. A way of ensuring the two meet up in a more pragmatic fashion could be useful.

3 At the moment we do not use 3D models to help us in locational planning for tall buildings. As we will see later, view management policies create invisible restrictive zones in the air, between which tall building proposals come forward. Better understanding of the three dimensional landscape, and policy implications for it, would greatly help us understand what we are doing. There was also a feeling that masterplanning could be better used to support good tall development, and prevent bad. 3D planning/city modelling could show areas likely to have pressure for tall buildings, partly because of the spatial impact of a variety of planning policies. Then attention can be given to looking at the actual size, position and role of taller structures in that area. Discussion continued that London Plan should make a greater distinction between dense and tall i.e. the CAZ / PTAL / town centre plan should indicate areas for building dense, whereas tall is appropriate and relevant to townscape, views and image and should be much more subject to urban form context as not much correlation between these is currently suggested. So all in all, the current London Plan is not very clear on the purpose of tall buildings for London and how we should be considering their spatial distribution. A simplistic assumption that they are a way of creating ever increasing densities and so are the thing to do in an increasing category of areas is probably not serving the city as well as strategic policies should be. It was very interesting that people seemed to generally like the existing policies, thought they said the right thing, but then did not think they were working well, blaming the way they are implemented. It could be argued that policies that are not well implemented are not the right policies. 2. The microclimatic and resource use of tall building proposals We were given a very interesting presentation listing the microclimatic and resource use issues the London plan does not cover at the moment. There was a clear view in the room that more should be done on this topic, maybe an SPG to give detail on how to assess what. Also stronger policies that explain a safe and pleasant environment around tall buildings, and sufficient daylight into the building, are essential, not just nice to haves. In the same way as the view management policies provide very detailed, mathematical thresholds which are highly influential of the shape and position of tall buildings, so too should these other physical requirements. As well as policy setting acceptability thresholds and guidance explaining how to test against this, there was a call for training and support for borough planners so they can understand and assess these issues better. The issues this suite of policy, guidance and training should cover included an overhaul of local wind assessments, to include consideration of the significant temperature reductions at pedestrian level around tall buildings, plus street pollution flushing effects, all areas that are important for amenity for those living or working in or around the buildings. Consideration is required at the initial design stage on what minimum daylight levels we want inside a building alongside how can we properly tackle overheating homes, particularly given the frequent loss of cross-ventilation in higher density buildings. Planning also has a key role in directing which methods are used for subsequent regulatory assessment, given the current Part L distortions which lead to undue high dependence on energy intensive mechanical solutions.

4 There was also significant concern over the way we deal with the cumulative effect of a number of tall structures in an area. Our system does not allow us to hold on to the issues and consider them all at the same time, while precedent can significantly degrade cumulative outcomes. Issues like daylight, sunlight and wind are by their nature borrowed effects from outside individual sites. Others, like Urban Heat Island Mitigation and Climate Resilience, and how they could be mutually complimentary, are accumulative benefits so most often lost for individual buildings. There was a concern with regard to tall buildings significantly increasing embodied energy, yet with the right guidance this could be countered by reconsidering longevity of buildings. Overall it was clear that we are not dealing with these issues well enough, we currently have a box-ticking approach to building tall, discouraging innovation, and not encouraging consideration of actual performance in use. We are potentially letting a lot of people down and storing up problems for the future. However, developing new policy and guidance in this area will not be easy, there are disagreements over the facts and standards, so for the GLA to take this forward for the next London Plan, an expert steering group for the topic might be useful. 3. Tall buildings as a form of super, or hyper dense development, and what this means for users We discussed what it is like for individuals and communities to live, work or set up businesses in dense areas. The potential benefits are vibrant and active areas; however, the pitfalls have been creating isolated, mono-communities, poor quality public realm and inefficient and expensive servicing requirements. Much of this comes down to good masterplanning. Not, as the word suggests, an authoritarian and inflexible blue print for an area, but a 3 dimensional, evolving framework within which proposals can be considered and tested. We were asked early on in the session whether we should be treating all tall buildings i.e. those over 10 stories, the same. Some felt that yes we should, because they all had the same issues in terms of how they met the ground, their relationship with neighbours, impact on local public realm and streets etc. But at the same time the impact of a 50 storey building is going to be very different from a 10 storey one. Maybe the same issues require consideration but at different scales of intensity and impact. We discussed the idea of a building being broken down and assessed on its component parts the important street frontage treatment and separately the parapet/plinth and tower element as these are seen and experienced differently depending on distance/views, heights and widths of street and skyline availability. This comes down to urban design and place management and how these can deal with medium, super and hyper density development. It was suggested at the last UDL Policy Symposium (click here for Briefing Note), that the London Plan needs a much better urban design policy, one that sets out the objectives being sought, from inclusion to safety, resource efficiency to community cohesion, and then the type of built forms that support achieving these objectives. Such a policy could be as relevant for low rise and super tall development, although nuances, and performance thresholds, for different types of development might be very useful. For example, the need to ensure tall residential towers were designed in a way to encourage community interaction and cohesion, and access to services, specifically because the way people move around such buildings, using lifts, can cause isolation. Similarly more stringent information and threshold requirements on service charges

5 might be needed for taller buildings, ensuring that there is a long term plan to generate enough income to properly maintain the buildings without extortionate costs to individual residents. Other key issues will be waste collection, consolidation of deliveries and local movement/transport capacity (not just public transport, but walking and cycling too). It should be possible to draw up a list of the practical, user orientated issues around residential developments of different intensities. Some of these will be based on the physical structure and quality of the area its urban design and some on ongoing management. Some will, of course, overlap with the climatic issues in Section 2 above. This might not necessarily be in a tall building policy, but could apply to tall buildings, nuanced depending on both the net site and gross area densities that would be achieved. 4. The relationship between the management of cityscape and views and the location and shape of tall building proposals. One thing that is very particular about tall buildings is the ability to see them from afar. The Plan manages visual impact through the London View Management Framework (LVMF) for strategically important views, and policies that suggest boroughs take a similar approach for locally important views. The methodology revolves around being able to see a particular building from a particular spot or area and then drawing geometric air shapes to ensure the view of that object is not blocked and what is seen around or behind it is considered. This approach is generally well understood and consistently implemented, although some practical issues, such as how to deal with moving views from bridges and the need to update the description of views were mentioned. In general it seemed that an update, with some tweaks, is all that is required. However two important issues were raised. First, how are we considering views and townscape issues away form these strategic views? And second, how well are we working with, and using, the influence of the view geometry in our spatial planning? In terms of the first of these, people from east and south London boroughs don t really have anything to do with the strategic views. They may or may not have drafted lists of local views, but it is a massive piece of work to create the detailed geometry in the LVMF for local views. The relative importance of a local view, or a change to the townscape to local communities, rather than to London as a whole, is not really dealt with, and the weight that should be given to visual change that does not relate to a historic asset is an issue that could do with further thought. There was discussion about what we like, or don t, and how we think about landmarks. This could be influenced by appearance, shape, size, position or connection (ability to use or relate to the buildings use). There were questions about whether new strategic landmarks should come forward to join St Pauls and the Palace of Westminster, and how we should be judging the quality, beauty and visual contribution of new buildings which lots of people will see for many areas. In terms of 3D planning, we were given a fascinating introduction to where some of the geometric air restrictions sit, and what this has meant for where tall building proposals have come forward. For example with them lining up behind each other as seen in a single view of St Pauls from the Thames, or being built along City Road in a wall shape because this is the space between two viewing corridors. He also explained how buildings are designed starting with the viewing corridor and rights to light air envelopes showing the maximum amount of cubic air space that can be taken up without effecting

6 these issues, and how the building shapes can then be carved to reflect these envelopes. Hence all our odd shaped tall towers, a product of invisible air space geometric policies. So, what next? Tall buildings and view management policies might not be one of the Mayor s priorities, they might not be highest on the list of things for the London plan team to look at, but they are important for London. There are many good ways of taking this forward, but here is one suggestion: Review and be clear, within the Plan, about the role of tall buildings; why we want them, where we want them and when and where we don t want them Take forward the debate on how we should consider landmarks (both strategic and local), public appreciation of townscape and architectural quality and what this means for policy requirements and assessment Review the density and urban design policies so they create a clear and firm basis for the assessment of tall buildings. Potentially nuance these to relate to low, medium, high and hyper density schemes and neighbourhoods and relate them to the urban forms that will meet the London Plan objectives Update the LVMF to deal with the in-practice issues being identified Use 3D planning to better understand where pressure for tall buildings will occur and proactively set out how they should develop in those areas Set threshold requirements for the performance of individual tall buildings in terms of: o Their climatic impact on their surroundings (wind/temperature/shadowing) o Their activity related impact on their surroundings (deliveries/waste collection) o The quality of internal environment (temperature, daylight levels, ability to interact with others, relationship between different users/occupiers and access to services) o Their maintenance and management regime and how this will be funded in the longer term Ensure there is greater balance between different policy areas so that those that are clear in mathematical terms do not take precedence just because they use numbers or geometry