The Labour leadership of Westminster Council has agreed important changes to the City Plan that will help deliver sustainable growth — bringing more jobs, more council homes but with fewer greenhouse gas emissions.
We are doing this by strengthening planning policies on retrofitting existing buildings, genuinely affordable housing, and by identifying four major sites for strategic development, including St Mary’s Hospital in Paddington.
Westminster’s new Retrofit First policy is likely to be one of the most consequential pieces of local government action on climate change anywhere in the UK.
The policy requires developers to fully explore all reasonable options to upgrade and adapt existing buildings before seeking permission for demolition and redevelopment. This is not a ban on redevelopment. We recognise that not every building can be retrofitted, which is why we are taking a retrofit-first, not retrofit-only approach.
Where redevelopment is supported, developers will be required to use the latest low-carbon construction methods, ensuring that new buildings meet the highest environmental standards.
The policy is already delivering results. Looking at 19 major schemes that went through planning in the first part of 2025, together providing 143,000 square metres of high-quality new and refurbished office, hotel and retail floorspace, the council has helped achieve a 24% reduction in construction-related carbon emissions compared to average emissions before the policy was published in 2023.
That represents a saving of 27,500 tonnes of CO₂, equivalent to the annual energy use of nearly 3,700 homes.
The City Plan review also strengthens our commitment to delivering more genuinely affordable homes to rent for Westminster residents.
Under the updated policy:
- 70% of affordable homes will now need to be at lower social rents, up from 40% under the previous Conservative policy
- Smaller sites, proposing fewer than 10 homes, will be required to contribute to affordable housing for the first time
These changes will help ensure that new development plays a meaningful role in meeting local housing need, particularly for families and key workers.
Strategic sites that deliver public benefit including St Mary’s Hospital
The City Plan identifies four strategic sites with significant potential for mixed-use development:
- St Mary’s Hospital
- Westbourne Park Bus Garage
- Land adjacent to Royal Oak
- Grosvenor Sidings
Specific policies for these sites will give developers and landowners the certainty needed to invest in new homes, modern workspaces, improved public spaces, and, crucially, a new, state-of-the-art St Mary’s Hospital, supporting the NHS for decades to come.
Cllr Geoff Barraclough, Cabinet Member for Planning and Economic Development, said:
“The City Plan Partial Review focuses our efforts on the most important challenges facing Westminster: delivering growth while tackling the climate crisis and delivering more genuinely affordable homes.
“Our Retrofit First policy sets a new benchmark for local authorities. It will reduce carbon emissions from today’s buildings and has the potential to be the single biggest emissions-reduction initiative undertaken by any council in the country.
“We are also strengthening our commitment to affordable housing by increasing the proportion of social rent homes in new developments and ensuring that smaller sites also play their part.
“Taken together, these policies create a roadmap to a fairer, healthier and more welcoming Westminster — one that works for today’s residents and for generations to come.”
The City Plan Partial Review will be formally approved by a meeting of Westminster’s Full Council on 19 January.