Protection of heritage assets not necessarily incompatible with tall buildings, experts say

With a record 436 tall buildings in the pipeline for London as of March of this year, it is clear that unchecked development has the potential to fundamentally alter the London skyline. But as the need for new housing and office space becomes ever more acute, there is no reason why – with the support of the planning system – sustainable development and the protection of heritage assets cannot co-exist.

The 1 Undershaft decision provides a practical example of how this balancing exercise should be carried out in practice and against a dramatic backdrop: what would be one of the tallest buildings in Western Europe, second only to the Shard. The City of London Corporation's Planning and Transportation Committee heard objections from local businesses and members of the public, and had to consider the building's potential impact on the setting of the Tower of London , which is a World Heritage Site.

It concluded that the planned tower's "simple and restrained" design, and its setting at the centre of a 'cluster' of similar buildings, was appropriate for the location. At the same time, the development would not "cause adverse impact on the World Heritage Site or its setting", or "compromise a viewer's ability to appreciate its outstanding universal value, integrity, authenticity or significance".

In its guidance of December 2015, Historic England attempted to grapple with these competing concerns within the context of the National Planning Policy Framework (NPPF). It found that well designed tall buildings, in the right place, can make a positive contribution to urban life, but those that are not have the potential to "seriously harm the qualities that people value about a place" by virtue of their sheer size and visibility.

Historic England recommends for local planning authorities to assess appropriate locations for tall buildings as part of their local plans, seeking advice from relevant public bodies where appropriate. The local plan should then be used to take a "positive, managed approach to development", rather than having local planning authorities respond in a piecemeal fashion to speculative applications.

For developers, the guidance suggests early engagement with local planning authorities as a matter of good practice, well in advance of a formal planning application. High standards of design, taking into account the potential effects of light and overshadowing from the building on the local environment, along with well-designed public areas are also essential.

It is clear that a developer's chances of successfully promoting tall schemes with impacts on heritage assets will increase by making the issue a priority from the start. This could mean as early as submitting representations during local plan promotion and at the stage of identifying sites for growth when it should be ensured that the significance of an affected heritage asset is identified appropriately.

Much will also depend on the tall buildings policy in the area. The London Plan's tall buildings policy is generally viewed as giving developers good scope for accommodating tall schemes within the setting of heritage assets with a relatively low threshold of 'particular consideration' to the impact of proposed schemes in sensitive locations.

It will be interesting to see how London mayor Sadiq Khan carries this forward in any forthcoming revisions to the plan. Whilst it might have been expected that the mayor would introduce a stricter policy for tall buildings, the recently published 'vision for London' consultation document merely sets out proposals for tall buildings to be required to add value to the existing community, with no mention of the link to any impact on the historic environment.

With its decision on 1 Undershaft, the City of London Corporation is an example of a planning authority that is getting this right. The planning and transportation committee praised the design of the building inside and out: it noted the "high quality internal environment that would support the health, wellbeing and comfort of the occupants"; and a public restaurant, viewing gallery, educational spaces and external piazza "similar to the Rockefeller Centre in New York".

These public benefits, combined with the scheme's ability to "make optimal use of the capacity of a site with high levels of public transport accessibility", were enough to outweigh the tower's impact on views and settings – not least because these impacts would not be sufficient to cause harm. Indeed, the committee concluded that the existing towers "provide a striking contrast in scale when seen in relation to the historic buildings and areas around them and are a defining characteristic of this part of the City".

As Chris Hayward, chair of the committee, said when the announcement was made, the 'Square Mile' will need to accommodate an additional 50,000 workers over the next 30 years - 10,000 of whom could potentially work at 1 Undercroft. With space at a premium building up, not out, in a way that adds value to the existing community makes logical sense.

Susanne Andreasen and Jennifer Holgate are planning law experts at Pinsent Masons, the law firm behind Out-Law.com.