Creating Climate Resilient Developments

Understanding the changing climate

Climate change is already being felt both across the globe, and locally, with the hottest day ever recorded in the UK recorded in 2022. In order to design for a changing climate, it is important to understand how the UK climate is expected to change. The Met Office has developed the UK Climate Projections 2018 (UKCP18) which illustrates a range of future climate scenarios until 2100. These show that that increasing summer temperatures, more extreme weather and rising sea levels are all on the horizon and urgent action is needed. The high emissions scenario shows:

  • Summer temperatures could be up to 5.4°C hotter by 2070, while winters could be up to 4.2°C warmer;
  • Sea levels in London could rise by up to 1.15 m by 2100;
  • Average summer rainfall could decrease by up to 47% by 2070, however there could be up to 35% more rainfall in winter.

Climate Resilience within our Sustainable Development Brief

Absolute emissions reductions remains our priority in order to mitigate the worst effects of climate change as can be seen in our Net Zero Carbon Pathway. It is however becoming increasingly apparent that the need for adaptation is equally important. With the requirements of the Taskforce for Climate Related Financial Disclosures (TCFD) becoming mandatory we anticipate businesses will become increasingly more aware of their climate risks. At Grosvenor Property UK, our TCFD disclosures are a function of a wider body of work to de-risk our portfolio, and we start at a building’s inception on the drawing board to ensure that current and future climate risk is mitigated.

Our developments need to display enhanced resilience and flexibility, with the ability to withstand potential adverse impacts of climate change, such as flooding and extreme weather patterns, including hotter summers, exacerbated by the urban heat island effect, alongside colder winters.

In order to design adaptation into our future developments, our Sustainable Development Brief is used for projects valued over £1m, ranging from major refurbishments to large new developments.

Climate Resilience is the first element our projects must consider and are assessed against the following criteria:

  • Future Climate Change – to future proof developments against the risks of climate change
  • Resilience to flooding – to future proof developments against the risk of flooding from all sources
  • Thermal comfort resilience – To future proof developments against the risks of extreme temperatures

During the design phase it is important to consider both current climatic conditions as well as predicted future climates to ensure that we both manage risk surrounding our assets as well as ensuring their future operational comfort and performance. See below a couple of examples of what we are doing on our development projects.

Holbein Gardens

Holbein Gardens is a redevelopment project of a 1980’s office building and is our first net zero carbon (in construction) office development. It aims to set a new benchmark for sustainable workplaces and building retrofit through the re-use of materials, and a holistic approach to embodied and operational carbon.

Future Climate Change
Resilience to flooding
Thermal comfort resilience

A climate change risk assessment was carried out to understand and mitigate the greatest risks for the project.

To reduce the likelihood of localised flooding, a detailed flood risk assessment was undertaken.

To ensure the building provides comfort both for current and future occupants, thermal comfort modelling was conducted both with current and future weather files.

Of the 37 identified risks, the three greatest risks were overheating due to hotter summers, freezing pipes and associated damage due to cooler winters, and surface water flooding and its impact on building services. For each of the 37 identified risks, responsibility was allocated to the relevant design team members to develop mitigating actions.

The proposed Sustainable Urban Drainage (SUDS) strategy provides a 92.5% betterment of the surface water discharge rate, whilst considering the numerous constraints such as the shallow outfall and adjacent London Underground station platform. This is achieved through the implementation of a deep blue-green roof and rainwater harvesting.

Thermal modelling was conducted to ensure compliance with best practice for both BREEAM and WELL certification. As a result, the design includes a mixed mode ventilation system. This uses a traffic light system on operable windows to highlight optimum conditions for natural ventilation. Exposed thermal mass was optimised to help regulate internal temperatures. This resulted in 100% of hours in occupied spaces operating within comfort bands for both current and future climate scenarios.

South Molton Triangle

South Molton Triangle is a mixed-use development in the heart of Mayfair’s conservation area. It contains New Grade A office floorspace with retail, restaurants, a 31-bed hotel and affordable private housing, all set amongst a reimagined high quality public realm.

Future Climate Change
Resilience to flooding
Thermal comfort resilience

A Climate Change Adaptation Strategy was developed for the project during RIBA Stage 2 to understand and mitigate the impacts of projected future climate change.

To reduce the likelihood of flooding a Flood Risk assessment and associated Drainage Strategy have maximised on-site attenuation.

A Passive Design Analysis and a Thermal Comfort Report were conducted to ensure the development provides ongoing comfort to occupants.

During a detailed review, 28 climate change adaptation and impact mitigation measures were identified. Key risks included the impact of subsidence or ground movement due to changes in soil moisture levels, in part due to the close proximity to Crossrail Tunnels. Warmer summers and heatwaves were also flagged as significant risks. Through early awareness the design team were successful in mitigating these risks through the building form and system design.

The Drainage Strategy system is designed based on a 40% uplift allowing for climate change in accordance with BS 8533, with on-site water attenuation designed accordingly. Any plant will be on plinths and in a bunded room to help prevent any flood impact.

The development maximises passive design opportunities to increase comfort levels without increasing energy demand. This includes looking at both the building envelope as well as thermal massing. Thermal comfort studies are conducted on both current and future climate change scenarios to ensure comfort is maintained for both current and future climate scenarios.  

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