Agenda item

Report of the Planning & Development Director.

The Sub-Committee considered a report of the Planning and Development Director which outlined changes that had been made to the way whole lifecycle carbon (WLC) of a development was measured and assessed through the planning system and the increased importance that had been given to encouraging the retrofit of existing buildings. This report sets out how policies in the City Plan could be updated to reflect these changes.

An Officer stated that the draft City Plan reflected the Corporation’s Climate Action Strategy in seeking to secure a net zero carbon square mile by 2040. He advised that since the previous version of the plan was drafted, the London Plan had been adopted and further guidance had been issued advising that reuse and retrofit should be prioritised in the planning system. There had also been increasing awareness in recent years of the need to consider the WLC of the built environment. As an intermediate step towards tackling WLC in the City, a Whole Lifecycle Optioneering Planning Advice Note was developed and this had recently been adopted by the Planning and Transportation Committee. It had been put into practice in the new schemes coming forward allowing the carbon intensity of different design approaches to be considered at an early stage. As the City’s plan was taken forward, there would be an opportunity to expand on this approach ensuring the City remained in general conformity with the London Plan and complemented the work on carbon options guidance.

The Officer stated that there were a number of places in the draft City Plan where there was the potential to give greater emphasis to a retrofit first approach. Firstly, the overall spatial strategy could be updated to recognise the importance of the WLC of new development and to promote the retrofit and refurbishment of existing buildings. Secondly, the policy on design could be updated, requiring design solutions to take a retrofit first approach by giving greater importance to the reuse and refurbishment of existing building structures and materials and by updating the supporting text as well as setting out the importance of retrofitting existing buildings, retaining embodied carbon and minimising WLC. Thirdly, relevant parts of Policy CE1 could be brought into the design section. This dealt with circular design principles and should be considered as part of the design of new buildings rather than just being viewed primarily as a matter concerning waste management. Fourthly, a policy requirement in the sustainability standards policies could be included to require major development proposals to demonstrate that they had considered multiple options for a site having calculated impacts in line with the carbon options guidance and that they had sought to minimise the WLC impacts of each option. the proposed scheme taken with these would have the effect of promoting retrofit and requiring developers to see it as the first choice. The Officer stated that this would not preclude demolition and redevelopment in all cases and there might be instances where other factors would outweigh the carbon impacts and the use of new materials that came with new development. However, it would act as a tilted balance giving greater weight to retention when development proposals were designed and considered by decision makers as well as ensuring carbon impacts were highlighted and circular economy design principles had been factored into the design of development proposals.

A Member asked how WLC compared between a notional high-rise building and two equivalent smaller buildings that provided the same office capacity. The Officer stated that in relation to existing buildings and the potential to retrofit and reuse materials varied significantly depending on the existing structure. The London Plan set out the overall spatial strategy for the whole of London and this was a densification approach rather than a spreading out approach based on solid long-term planning principles like reusing existing sites, concentrating development in certain places and optimising and making the best use of the public transport facilities. The Corporation had invested £200m to support the Crossrail development, the development had paid a significant sum through the Community Infrastructure Levy and the transport infrastructure meant that promoting the growth of office development within very well-connected places like the City was a sustainable approach as people could get to the City without using cars. It also meant that building was not spreading out into the countryside and using land that could be used in other ways to support climate action, e.g., putting carbon back into the ground as was being considered in Epping Forest and other places across the green belt. The Officer stated the importance of being aware of the special strategy as the Corporation’s Local Plan had to be in general conformity with the London Plan and had to comply with the approach taken in the National Planning Policy Framework which reflected that. There was a strong sustainability argument for creating dense development within well-connected places on a building-by-building basis. The Officer stated that in general the WLC of high-rise buildings was higher than the WLC of equivalent lower-rise buildings. However, it also depended on the design of the buildings. The majority of embodied carbon went into the steel and concrete structures of buildings. Tall buildings had to be heated and cooled differently to smaller buildings and less natural ventilation might be possible. The Officer stated that there were significant constraints in terms of development potential in different parts of the City with a series of conservation areas, over 600 listed buildings and strategic views. An office demand study was being undertaken to give a greater idea of the scale of growth that would be requirement and shape the pattern of development.

The Chairman stated that in terms of longevity, iconic buildings tended to have a much better WLC opportunity than smaller equivalent buildings. Activating ground floor space by including food, beverage and leisure opportunities was important when looking at the carbon footprints of those travelling into offices to work. It would often mean the entire day of an employee could sit on their employer’s carbon footprint and these aspects should be considered.

A Member commented on the impact tall buildings had on surrounding buildings e.g., in relation to solar gain as this had an impact on the energy performance of these buildings. The Officer stated that the impacts would be considered. He stated that buildings were being designed to minimise operational carbon demand from heating, cooling and power and also with grid decarbonising the actual power to run the buildings was reducing. The Member stated that it was important the disbenefits did not fall disproportionately on others. The Officer stated that when planning applications were submitted, the impact of the buildings on the wider area were considered. The BRE daylight and sunlight guidance required the impact of a building on solar panels in neighbouring buildings to be considered. Consideration was also given to the impacts on green roofs and other urban greening.

A Member asked if a mechanism could be built into the Local Plan that would mean if a developer demolished a building before a 60-year life, they would start with a carbon debt of whole life carbon that was assumed in the building that had been demolished. He stated that this would give a strong incentive to construct buildings that would be in place for over 60 years because replacing them any earlier would be challenging. A Member asked whether 10 years after construction, a review of the performance of a development relative to projections could be undertaken. The Chairman stated that disincentivising developers to redevelop early should be embedded. Officers would consider the implications of this. An Officer clarified that the embodied carbon was not in the building but was in the construction of the new materials, so the age of a building was less significant that the amount of carbon involved in replacing it. He also stated that if replacing buildings between 5 and 20 years became an increasing trend, the rate of development would become an issue and therefore consideration should be given to slowing down the rate as a whole.

A Member suggested that where buildings were demolished and had a carbon debt of WLC, they could be charged a surcharge on the Community Infrastructure Levy (CIL) to disincentive demolishing and promote extending and retrofitting.

A Member commented that a building should only be permitted to be demolished if it was deemed acceptable and policies should not look backwards. He stated that most developers were now looking at retrofitting first as a matter of course.

A Member stated that even if a building was 20 years old, it may have been poorly designed, or circumstances may have changed, and it was important to look at each case on its merits. Demolishing and rebuilding could be the most suitable course of action.

A Member stated that the complexity of retrofitting should be included in the documentation e.g. ceiling heights could prevent the installation of a mechanical ventilation system, modern buildings had to be insulated but if there was a solid brick structure, it would not be possible to install external insulation. If the building was in a conservation area, internal insulation would compromise fixings on the walls and could result in moisture and condensation. If there was a late Victorian building with poorly cemented steel, adding insulation could result in corrosion.

An Officer stated that a significance number of planning applications were now for retention and retrofits of buildings up to 40 or 50 years old. The default position was now to retrofit.

Officers stated they were involved in each scheme, exploring in great detail the opportunities for retrofit an the limitations of that, the opportunities for partial retention and for minimising WLC. The Officer stated that the approach set out in the paper acknowledged the complexities but did not set out a threshold for demolition or retrofitting. It deliberately reflected the complexities of the issues by taking a balanced approach.  It focused on having tilt in that balance to give additional emphasis to the need to retain existing components, existing buildings, to reuse materials and to develop circular economy. The Officer stated that there could be situations where a retrofit and adding an additional five or six storeys on a building could have a similar carbon impact as demolishing and rebuilding due to the strengthening work that would be required to support the additional floors. There could be other buildings where due to the fabric of the existing building and its foundations, this could be achieved with relatively limited carbon impacts. There were also wider sustainability issues such as providing better mechanical ventilation systems, plant and machinery, solar panels on the roof, green roofs and climate resilience. The wider planning aspects of the opportunities of the scheme could then be considered. This was reflected in the Carbon Options Guidance which was broadly accepted by the development industry as an exemplar process. This was why the balanced view approach had been set out in the plan.

In response to a Member’s question, an Officer advised that the terms of a CIL was set by national government. It was set on the uplift of floorspace that a scheme delivered and therefore the Corporation could only determine the rate at which the CIL was charged.

In response to Members’ concerns about buildings being demolished much sooner than the expected 60 years, Members were informed that Officers would explore possible approaches to address this. The Officer stated that the approach outlined in the policy was looking to promote circular economy design principles and building buildings for longevity and adaptability was vital to prevent new applications in 20- or 30-years’ time to demolish buildings that were currently being constructed. The Officer advised that many applicants were future-proofing buildings.

A Member commented that having policies in place to make it unviable to be demolishing buildings could address some of the issues raised and having a robust first gate test would achieve this. He stated that there should be the proper utilisation of space as it was irresponsible from an environmental perspective not to properly utilise space. He further stated that it was important that polices were forward looking.

A Member commented that businesses were now considering their carbon footprint and were surveying staff and users about where they travelled from, stayed and how they travelled, to better understand their impact on the environment.

In response to a Member’s question, the Chairman stated that although Members were looking at one particular aspect of the City Plan, the retrofit policy, it had to be considered in context with developers, employers and the market also being considered. A Member stated that policies had to balance sustainability and have regard to the market and the Corporation was backed by most of the development industry and was seen as leading the way. The Chairman stated that the Planning Department had been shortlisted for awards on Carbon Optioneering Guidance and various aspects of the approach to sustainability.

A Member asked Officers for more information on Retrofit Fast Track. An Officer started that this would be brought back to the Sub-Committee in June 2023 once evidence on office demand had been received. The Officer stated that where an existing building was retained, there could perhaps be an easier route through the planning system towards changing from office use towards another use that would complement the business City, e.g., education use, research and development, other forms of office space e.g., to support Small and Medium Enterprises (SMEs) and creative industries. Officers would be giving further consideration to this. A Member commented that standards should not be relaxed and WLC assessments should still be undertaken as without these, the reuse of buildings could make them operationally inefficient.

The Chairman outlined points made by a Member who had sent apologies. She stated that she considered that the policy should be expanded to embed a retrofit first approach and provide a retrofit fast track to incentivise this. She considered that the plan’s spatial strategy could be amended to specifically recognise the importance of the WLC of new development and the need to promote the retrofit and refurbishment of existing buildings. She stated that this approach would reflect the aims of the Corporation in promoting sustainable development in line with the Climate Action Strategy and would allow for greater weight to be applied to the retention of existing buildings and structures in decision making.

In response to points raised by the Member in relation to the definition of Tall Buildings, the Chairman stated that there were statutory definitions of spaces.

In response to Members’ questions, the Officer stated that in general, the development industry was in support of retrofitting. Office uptake of redeveloped spaces had been increasing in the past 5-10 years. The City Property Association (CPA) had published their own ‘Retrofit First, Not Retrofit Only’ study which looked at different case studies. The Officer stated that some developers and landowners were already making firm commitments to taking science-based targets in across their portfolios of development and looking at specific targets for the WLC of their new developments as well. The level of support to the planning advice note was evidence that there was industry-wide and stakeholder-wide support.

A Member stated the importance of preserving office space in the City and not approving sub-standard residential accommodation and stated this should be reflected in the policy. An Officer stated that the City was exempt from the permitted development rights to convert offices to residential use. This had been secured through the Article 4 Direction which was endorsed and supported by the government at a time when they were looking to restrict the ability of local authorities to bring in Article 4 Directions. This was a clear national steer to maintain the City’s functions. In addition, the London Plan set out clear policies that required the City to prioritise and promote office development above residential development within the square mile. The Officer stated that he would advise against any approach which sought to make change of use to residential a more straightforward process than was already in the draft City Plan.

RESOLVED - That Officers continue to progress work on the City Plan based on Members’ views on the proposed policy direction in relation to the ‘retrofit first’ policy approach and draft amendments to the spatial strategy for the draft City Plan.