This article looks at the latest developments in the UK relating to the height of buildings – both in terms of safety and value.
There’s also a look at what this means for owners, investors, landlords and tenants, as well as the services offered by North London estate agent Maunder Taylor.
It will take between three and four minutes to read.
The UK skyline is undergoing a massive transformation, but how we view a building’s height depends entirely on whether it is a commercial or a residential block. Here, Maunder Taylor, who keep a close eye on all property-related trends (particularly as they affect the London and Hertfordshire areas), take a closer look at the latest developments in 2026.
Maunder Taylor – a Comprehensive Range of Property Services in North London
Maunder Taylor offers a complete range of property (and associated legal) services in and around London. So if you are interested in commercial properties to let in Barnet, need property valuation surveyors in Potters Bar, or require residential block management services in Welwyn Garden City, you can contact us.
The Commercial Sector
In the commercial sector, height is a symbol of economic ambition. The City of London recently granted full planning consent for One London (the site formerly known as 1 Undershaft). Standing at an astonishing 309.6 metres, this 74-storey building will match the pinnacle of The Shard, making it the joint-tallest building in the UK and Western Europe. Both towers are legally capped at this height due to strict London aviation ceilings and flightpath constraints.
To clear the way for this £1 billion project, contractors are currently demolishing St Helen’s Tower, which was originally built in the 1960s. At 118 metres tall, it represents the largest skyscraper ever intentionally demolished in London – a clear sign that older, less efficient commercial assets are being aggressively phased out to make way for highly sustainable, more modern workspaces.
The Residential Sector
However, while commercial developers are looking to the sky with renewed confidence, the residential sector is looking at building heights through a strictly regulatory lens. For residential blocks, height is no longer just about views or architectural flair; it is the definitive boundary for safety legislation.
The biggest regulatory shift on the horizon is the implementation of the second staircase rule. By late September 2026, all new tall residential buildings over 18 metres in height (approximately five to six storeys) must feature a second staircase to secure building safety sign-off.
This mandate is fundamentally changing the economics of residential development, forcing architects to redesign layouts to accommodate extra core space, potentially squeezing profit margins or requiring additional floors to maintain financial viability.
Simultaneously, the regulatory net is widening for existing structures. New legislative updates, including the latest versions of the Building Safety Act, are placing much tighter scrutiny on multi-occupied high-rises. The Act was prompted by the Grenfell Tower fire in 2017, which claimed the lives of 72 people and led to many more being made homeless.
Now, height dictates everything from the complexity of mandatory Fire Risk Assessments to the depth of structural safety cases required by the Building Safety Regulator.
Navigating the Horizon with Maunder Taylor
Whether managing an existing asset or planning a new one, a building’s height now dictates its compliance framework, its insurance risk profile, and its ultimate market value. For landlords, developers, and block management committees, these contrasting trends create a complex property landscape.
As the demolition of St Helen’s Tower proves, commercial spaces must continuously adapt. If you own or lease commercial property, understanding how to modernise layouts to meet modern Energy Performance Certificate targets and evolving workspace demands is crucial. Maunder Taylor’s professional valuation and rent review services ensure your commercial investments will remain competitive in an evolving market.
For those managing or owning residential blocks, navigating the rules surrounding buildings over 18 metres tall requires dedicated expertise. From managing rising insurance premiums to ensuring that service charges adequately fund required safety upgrades, meeting the demands of modern block management is more complex than ever before.
Contacting Maunder Taylor
As Chartered Surveyors and Property Consultants across London and Hertfordshire, Maunder Taylor can help you navigate these shifting horizons. Whether you need to assess the structural valuation of a commercial asset or require expert guidance on high-rise residential compliance, our team ensures your property stands on firm ground.
Contact Maunder Taylor today to discuss your commercial valuation or block management needs. You can call 020 8446 0011 (our head office) or 01707665666 (for residential management inquiries).
FAQs
Q: Is there a maximum height for buildings in the UK?
A: Local planning authorities dictate maximum heights in their Local Plans, often heavily influenced by local aesthetics, overshadowing (“right to light”), and aviation or transport sightlines.
If the building is at least 18 metres high, has at least seven storeys, or contains at least two residential units, then this triggers more stringent safety requirements. Apart from the soon-to-be-mandatory second staircase, there also needs to be stringent external wall system assessments, and registration with the Building Safety Regulator.
Q: Does the 18-metre “second staircase” rule apply to existing buildings?
A: No, it specifically targets new residential developments in England. If you manage or own an existing single-staircase block, you are not legally required to build a second one.
Q. What happens if a development layout was designed before the rule change?
A: The transition period officially ends on September 30, 2026. New schemes that do not have a building control application “sufficiently progressed” (meaning the pouring of foundations or piling has physically started) by this date must be redesigned to include a second staircase core. For many developers, this requires a formal Section 73 planning variation to adjust the building’s scale or massing to offset lost internal floor space.
Q: How do these new height regulations affect property valuations and insurance?
A: For residential blocks over 18 metres, insurance premiums have risen due to the strict risk profiles now required by underwriters. For developers, adding a second staircase can reduce a building’s net internal (saleable) area by several percentage points, directly impacting development viability and eventual asset valuation.