The NLA Expert Panel on Tall Buildings reconvened this month to consider the justification for tall buildings and what criteria are being used to assess them. We also considered the ‘pipeline’ of 20-storey tall buildings and why this seems to have stalled.

The Panel kicked off the discussion with some thoughts on ‘why we need to build tall?’ citing the need for new homes and commercial spaces and the scarcity of development land in London. It was acknowledged that cynicism towards tall buildings seems to have become embedded in our culture largely influenced by negative opinions on poorly maintained 20th-century buildings but also more recently concerns about foreign owners and unoccupied towers and of course building safety.  

It was suggested that Planning Authorities have become somewhat apologetic about ‘height’ but that they and developers need to work together to help people understand the locational rationale for tall and the genuine public benefits that a tall building can deliver. Early engagement is key. Successful schemes should ‘give back’ to the community rather than simply mitigate their impacts.

Clearly, it is also important that the design of these buildings optimises a site, creating an intensity of the experience for a range of stakeholders including spaces which encourage ‘community’ and social interaction as well as becoming carbon neutral and planning for the long term life and evolution of the building.

Post Grenfell, residents and future residents need to feel safe rather than simply being told they are safe. This is something that the Building Safety Act reforms should help address, in particular, the role of a ‘nominated person’ responsible for ensuring a building remains safe and communicating with residents and building users.

The ‘lived-in experience’ for residents of tall buildings was roundly considered not to have been properly measured and this is something the Panel concluded would be beneficial information to collect post-occupation. It could become a Section 106 obligation for the Local Authorities or GLA to collate and would help address the wider cynicism that exists.

The discussion moved on to a debate about ‘the planning criteria for tall buildings’. It is recognised that national planning guidance has pushed the progression of design guidance and design codes and that the latest London Plan requires greater emphasis on height and location. London Plan policies also require significantly more information across a broad range of impacts but is it too impact driven and does this stifle design quality?  

Historic England’s Advice Note highlights the need for local distinctiveness to be recognised. The Advice Note highlights the importance of character, setting, sightlines and views and that cumulative impact is important when considering the potential impact of a cluster of tall buildings. We must think of new tall buildings as being the heritage of the future.

There was debate however about whether the impact-based approach is reasonable and it was suggested that communities and stakeholders do not necessarily recognise the planning criteria and why they are applied in the local context. The idea that local politicians know what’s best for communities is often disputed and would communities rather be involved in the framing of and evolution of schemes. Planning Officers often find themselves having to justify the Council’s policies rather than defend the merits of the scheme itself. 

There was almost universal agreement amongst the Panel that the London Plan requirement for an area-based height threshold is very difficult for a Local Authority to address. This can only really be addressed on a site-by-site basis as an appropriate and nuanced approach and it is developers that have the capacity, means and technical teams that can model and test this rather than Local Authorities attempting to do it in a vacuum. 

There is also frustration about an overly rigid application of design criteria including eight units per core which it is felt stifles design creativity and, in certain cases, the restriction of north-facing single aspect units where a view over the Thames or a significant green space might be a very attractive outlook.

A view that we did not have enough time to discuss and will return to at a future debate was “why have planning policies resulted in a degree of mediocrity in built schemes” when policy has consistently sought high-quality architecture and exemplary schemes?

The final area of discussion focused upon the ‘build-up of unimplemented tall building projects’, citing the NLA Tall Building Survey of 2022 which highlighted that some 340 projects had planning permission but had not yet moved to construction.  

Knight Frank had run some further analysis of this grouping, concluding that planning permission duration (generally three years), project financing, site preparation and pre-commencement obligations would mean there is a natural gap between planning consent and formal start on site.  It is also the case that many of these schemes would be subject to Outline Planning Permissions and Masterplan phasing that allow for 10-15 years of phased construction delivery. On this basis, it is more like 50-60 schemes that have actually stalled which is still a considerable volume.

Some key themes highlighted by the Panel affecting the delivery of these stalled schemes include:

 

It was observed that there have been no really significant innovations in construction that would speed up the delivery of tall buildings. Whilst there are some examples of MMC in terms of modular build and the use of CLT this is taking time to be embraced at any scale in the UK construction sector.

 

In conclusion, therefore, it seems there remains an appetite for tall buildings underpinned by land supply and housing and Grade A office needs.  However, building costs and market volatility are having a significant impact. Planning policies do not provide enough flexibility to encourage exemplary design and communities need to be engaged meaningfully at the concept stage but also post-development to really understand the experience of living or working in and around tall buildings.

 

Our next meeting will focus more closely on the sustainability context for tall buildings including the use of technology and data in promoting sustainable schemes, to support the newest edition of the NLA London Tall Buildings Survey coming out in March 2023.