20 Fenchurch Street

Previous building

The previous building at 20 Fenchurch Street was 91 m (299 ft) tall with 25 storeys and was built in 1968 by Land Securities. The architect was William H. Rogers.

The building was formerly occupied by Dresdner Kleinwort and was notable for being one of the first tall buildings in the City of London, and for its distinctive roof. It was one of the towers nearest to the River Thames when viewed from the southern end of London Bridge.

In 2007, one of the upper floors was used in the drama series Party Animals.

Demolition of the building was completed in 2008. Despite the top-down method of construction, it was not demolished from the bottom-up, as a temporary structure was built, allowing Keltbray, the demolition contractor, to demolish the building from the top down.

Design

The new tower at 20 Fenchurch Street was designed by Uruguayan architect Rafael Viñoly in a postmodern style. The top-heavy design is partly intended to maximise floor space towards the top of the building, where rent is typically higher.

The building utilises double and triple-glazed panelised aluminium cladding on its exterior.

The 'sky garden' at the top of the building was claimed to be London's highest public park, but since opening there have been debates about whether it can be described as a 'park', and whether it is truly 'public' given the access restrictions. The garden spans the top three floors, which are accessible by two express lifts and include a large viewing area, terrace, bar and two restaurants. Fourteen double-deck lifts (seven low-rise up to the 20th floor, seven high-rise above the 20th floor) serve the main office floors of the building.

The south side of the structure is ventilated externally to improve efficiency and decrease solar gain, whilst the east and west faces incorporate extensive solar shading. There is a southern entrance in addition to the main northern entrance set back from Fenchurch Street.

Construction

In January 2009, Canary Wharf Contractors began piling on the site of 20 Fenchurch Street. Piling and ground works were completed in June 2009.

In January 2011, work at the basement level of the tower began. By the end of October 2011, the building was rising above street-level. December 2011 saw the tower's core begin to rise. The concrete core was topped out in March 2012 and by July the structural steelwork was under way around the core. Structural steelwork topped out in December 2012.

Fire protection contractor Sharpfibre Ltd began applying fire protection to the structural steelwork in December 2012, completing in March 2013. Cementitious spray was applied to the steelwork, which was supplied directly to the entire building using a purpose-built mixing and pumping station located on the ground floor.

The building completed to shell and floor in April 2014 and the first tenants began moving into the building from May 2014 prior to final completion in August of that year.

Awards

The building won the Carbuncle Cup in 2015, awarded by Building Design magazine to the worst new building in the UK during the previous year. The chairman of the jury that decided the prize, Thomas Lane, said "it is a challenge finding anyone who has something positive to say about this building", whilst a town planner at the nearby Royal Town Planning Institute described the building as "a daily reminder never to let such a planning disaster ever happen again."

Solar glare problem

During the building's construction, it was discovered that for a period of up to two hours each day if the sun shines directly onto the building, it acts as a concave mirror and focuses light onto the streets to the south. Spot temperature readings at street-level including up to 91 °C (196 °F) and 117 °C (243 °F) were observed during summer 2013, when the reflection of a beam of light up to six times brighter than direct sunlight shining onto the streets beneath damaged parked vehicles, including one on Eastcheap whose owner was paid £946 by the developers for repairs to melted bodywork. Temperatures in direct line with the reflection became so intense that a reporter for the newspaper City A.M. was able to fry an egg in a pan set out on the ground. The reflection also burned or scorched the doormat of a shop in the affected area. The media responded by dubbing the building the "Walkie-Scorchie" and "Fryscraper".

In September 2013, the developers stated that the City of London Corporation had approved plans to erect temporary screening on the streets to prevent similar incidents, and that they were also "evaluating longer-term solutions to ensure the issue cannot recur in future". In May 2014, it was announced that a permanent awning would be installed on the south side of the higher floors of the tower.

The building's architect, Rafael Viñoly, also designed the Vdara hotel in Las Vegas which reportedly has a similar sunlight reflection problem that some employees called the "Vdara death ray". The glass has since been covered with a non-reflective film.

In an interview with The Guardian, Viñoly said that horizontal sun-louvers on the south side that had been intended to prevent this problem were removed at some point during the planning process. While he conceded that there had been "a lot of mistakes" with the building, he agreed with the building's developers that the sun was too high in the sky on that particular day. "[I] didn't realise it was going to be so hot," he said, suggesting that global warming was at fault. "When I first came to London years ago, it wasn't like this ... Now you have all these sunny days."

Sky garden

The 'sky garden' has been criticised since opening for the tight restrictions and advance booking requirements placed on the visiting public, and for failing to meet pre-construction expectations of the extent and quality of the "garden". Oliver Wainright, architecture critic of The Guardian, described it as "a meagre pair of rockeries, in a space designed with all the finesse of a departure lounge".

The City of London Corporation's former chief planner, Peter Rees, who approved the structure, said: "I think calling it a sky garden is perhaps misleading. If people [are] expecting to visit it as an alternative to Kew, then they will be disappointed." In July 2015 it was reported that planners are to consider a landscape architect's alterations to the layout, following claims it is not consistent with illustrations submitted with the original planning application. The 'sky garden' was a key feature in sealing approval for the building, which is situated outside of the main cluster of skyscrapers in the City.

Wind tunnel effect

In July 2015 it was reported that the building has had an unexpected impact on wind strength at street-level. The City of London Corporation received an increased number of complaints about draughts around 20 Fenchurch Street following its completion. The Corporation's head of design, Gwyn Richards, said: "The wind outcome at street level experienced post-construction on a number of projects differs somewhat to the conditions we were expecting from the one outlined in the planning application wind assessments."

Tenancy

In June 2012 the insurer Markel Corporation signed a tenancy agreement with the developers to move into 20 Fenchurch Street upon its completion. Markel, previously based on Leadenhall Street, was the first confirmed tenant of the new tower and occupies the 25th to 27th floors.

Another insurance company, Kiln Group, announced in September 2012 that it had agreed to become the building's second tenant and Ascot Underwriting followed in November 2012. Other insurance companies that have taken space in the building include RSA Group, Tokio Marine, CNA Financial, Allied World, Liberty Mutual's European operations, and Harry Townsend Corp.

Other lettings have been agreed with Castleton Securities, Vanquis Bank, Jane Street Capital, DBRS, and lawyers DWF. Vinson & Elkins has signed a lease to take a floor of the building ahead of a summer 2015 move-in, meaning 98% of the available space is leased.