1 Undershaft
![]() |
In November 2016, the City of London Corporation granted planning permission for the latest skyscraper development, which will be western Europe's second tallest building.
1 Undershaft, or the 'Trellis Tower' as it has been nicknamed, was designed by Eric Parry Architects with WSP as structural engineer. It will be located in the heart of the City of London.
At 73-storeys and a total height of 304.94 m, the tower will overlook its neighbours, the Leadenhall Building and The Gherkin, but is just a little shorter than the Shard, currently the tallest building in western Europe. However, the tower will be able to lay claim to the highest occupiable floor.
Approximately 90,000 sq. m of office space will be provided, playing host to 10,000 workers. Maximum usable floor space will be achieved by the offset design of the core and the 'exoskeleton' bracing.
A free public viewing gallery will be included at the top of the building, which will also contain the city's highest restaurant. There are also ongoing talks with the Museum of London about the possibility of including a dedicated exhibition space.
At the base of the tower, a new public square will be created, with the public able to walk beneath the skyscraper, with the main office reception above.
The project is being developed by the Singaporean firm Aroland Holdings. The existing Aviva Tower is to be demolished before construction work on the new structure begins, with an estimated completion date in the 2020s.
Eric Parry said, “I wanted to do something calm. It is the last piece in the jigsaw, so I wanted to do something that isn’t flamboyant.”
Chris Hayward, chairman of the City’s Planning and Transportation Committee, said, “I’m delighted that we have approved 1 Undershaft. It is a truly unique building that fits in well with the City’s history, as well as our future ambitions for growth. This development shows the high levels of investor confidence in London’s status as a global city following our decision to leave the European Union.”
Image courtesy of Eric Parry Architects.
1 Undershaft received planning permission in November 2019.
[edit] Related articles on Designing Buildings Wiki
- BT Tower.
- Leadenhall Building.
- Lloyd's of London.
- Supertall.
- Tallest buildings in the world.
- The Gherkin.
- The Shard.
[edit] External sources
Featured articles and news
How can digital twins boost profitability within construction?
A brief description of a smart construction dashboard, collecting as-built data, as a s site changes forming an accurate digital twin.
Unlocking surplus public defence land and more to speed up the delivery of housing.
The Planning and Infrastructure bill oulined
With reactions from IHBC and others on its potential impacts.
Farnborough College Unveils its Half-house for Sustainable Construction Training.
Spring Statement 2025 with reactions from industry
Confirming previously announced funding, and welfare changes amid adjusted growth forecast.
Scottish Government responds to Grenfell report
As fund for unsafe cladding assessments is launched.
CLC and BSR process map for HRB approvals
One of the initial outputs of their weekly BSR meetings.
Architects Academy at an insulation manufacturing facility
Programme of technical engagement for aspiring designers.
Building Safety Levy technical consultation response
Details of the planned levy now due in 2026.
Great British Energy install solar on school and NHS sites
200 schools and 200 NHS sites to get solar systems, as first project of the newly formed government initiative.
600 million for 60,000 more skilled construction workers
Announced by Treasury ahead of the Spring Statement.
The restoration of the novelist’s birthplace in Eastwood.
Life Critical Fire Safety External Wall System LCFS EWS
Breaking down what is meant by this now often used term.
PAC report on the Remediation of Dangerous Cladding
Recommendations on workforce, transparency, support, insurance, funding, fraud and mismanagement.
New towns, expanded settlements and housing delivery
Modular inquiry asks if new towns and expanded settlements are an effective means of delivering housing.
Building Engineering Business Survey Q1 2025
Survey shows growth remains flat as skill shortages and volatile pricing persist.