Heathrow T5 - on time, on budget and taking shape

BAA’s planning application for the £4 billion T5 project was submitted in February 1993. After the longest, most detailed public inquiry in British planning history, the government gave the go-ahead for the huge project in November 2001.

Now, with almost two thirds of the work completed on time and within budget T5 which will be the new home of British Airways, is an example of how future large-scale projects in the UK might be managed.

After the problems encountered with many of the Millennium projects, the Scottish Parliament building and the Wembley National Stadium, perhaps planners for the 2012 Olympic project could learn from the T5 model.

The concept

Richard Rogers Partnership design team worked closely with a multitude of end-users including HM Customs and Excise and retailers as well as the BAA itself, each with different requirements, in an attempt to fully integrate the project.

The single span roof provides a vast and flexible interior space that can be easily adapted according to the changing demands of the aviation industry. Travellers will experience simplified circulation and shorter walking distances.

After check-in, customs and security, departing passengers will descend from the departure lounge to the gates below. As the facades of the building are glazed, the passenger is set to enjoy out-standing views of the airfield.

Arriving passengers will make their way into an open arrivals concourse that reveals the interchange plaza, a 30m wide pedestrian area running the length of the terminal. Glazed sky bridges span the interchange plaza and will connect the terminal with bus, coach and taxi facilities integrated into the forecourts of the multi-storey car park. Glazed express lifts at the northern end of the plaza will connect rail services with the departures and arrivals concourses below.

Staggering statistics

Facts, figures and statistics about the Heathrow expansion are simply staggering. The 16 projects and 147 sub-projects include: the diversion of two rivers and the subsequent transfer of their 40,000 fish; the boring of 13.5km of tunnels; the curtain walling of the vast 400m x 150m T5A building and its two large ancillary buildings; plus the erection of an 87m Air Traffic Control Tower – on the busiest aircraft taxiing area in the world – and all with no disruption to air traffic.

The largest project currently under construction in Europe covers an area roughly the size of London’s Hyde Park. The 260 hectare site is constructed on land that was previously occupied by Thames Water’s Perry Oaks sludge works – ‘So no complaints about it having been built on a green field site’, says BAA’s Ian Guy, Senior Development Manager for T5.

In its own right, the T5A building would be the fourth largest airport in Europe and over 60,000 people are expected to work on the project throughout its construction. While T5 will not add any additional runway to Heathrow, the extra space alone will boost capacity from 60 million to 90 million passengers per year.

Glazing solutions

Despite the complexity and sheer scale of T5, Schmidlin Ltd Façade Technology, have worked closely with BAA and HEK Manufacturing to develop technical solutions and install the T5A curtain wall on time and on budget.

Schmidlin have worked in close partnership with BAA since working on the Gatwick Air Traffic Control Tower in 1980. Since then, they have worked on 20 projects together.

A test section of the cladding system was made and provided the team with a list of 140 possible improvements. Some of the framework from the prototype is actually included in the actual T5A structure.

Schmidlin had to design, manufacture, test and install 33,000m2 of bespoke curtain walling, consisting of 5,565 individual elements. On the east and west elevations – spanning 400m and glazed from the exterior – the elements have a dimension of 3m x 2m. On the North and South side – spanning 150m, glazed from the interior – they measure 3m x 1.8m.

The glass units have laminated inner and outer panes with a high performance coating on the second surface. The glass used to make up the unit construction varies from 12.76mm to 13.52mm thick with a larger than usual integral air space to enhance acoustic performance. Parts of the western elevation were glazed with blast enhanced units as this is the side opposite the car park.

Challenges

The main challenge lay in the large structural movement due to the huge spans that had to be accommodated by the façade. Schmidlin’s solution included the development of probably the world’s longest gasket: an extruded movement gasket, which was integrated into the façade design.

A further challenge was to find a solution for the external shading system. Even after coating the glass, solar gain levels were too high.

A Brise Soleil was designed comprising 6m long blades and hung from the roof via 50mm diameter solid stainless steel rods and cast stainless steel connectors.

Having to install two 400m long facades with an outward inclination of 6.5 degrees, a roof soffit overhang of 8m and the limitation of not being allowed anchors or ties, called for a special installation solution.

Schmidlin’s solution included the development of probably the world’s longest gasket

Together with T5 partners, HEK Manufacturing, Schmidlin created a mast climbing work platform mounted on a bespoke rail track system that could travel the whole length of the façade (pictured right).

The special construction had to incorporate sufficient load capacity for the glazing element manipulators and have enough storage area for a day’s supply of elements.

Elements were installed at a rate of 10 per side per day on the east and west elevation, making a total of 20 elements installed per day.

Such excellent progress was only possible through close partnerships with BAA and HEK Manufacturing. Installation is progressing well ahead of programme; all key façade milestones have been achieved while remaining on budget.

Glass Specifications

All elevations of the main terminal building (T5a) are glazed with Guardian Glass’s SuperNeutral 63 (SN63) except the north elevation which uses Guardian’s Climaguard 1.1 Nuetralite Lowe.

Polypane in Belgium took delivery of the 40,000m2 glass required for the laminated outer pane, and the same quantity for the inner pane which is clear float laminated.

For the roof, there is a further 8,000m2 of toughened and heat soak tested SN63 which is being installed by Hathaways.

Polypane completed supply to Schmidlin for installation in mid-August 05.

Logistics

Having almost no site storage available, one of the first steps was to create a complete off site logistics centre. A logistics team was permanently based at the Heathrow warehouse complex to deal with deliveries from the manufacturing plant in Aesch, Switzerland and transport to the site.

Approximately 10,000m2 of storage space were required for the T5A façade materials. The pre-assembled glazing elements arrived from Switzerland in eight lorries a week and the unitised construction needed a very precise production sequence. Stillages were delivered to the site with glass loaded in the correct order to minimise handling.

Bringing vast quantities of other materials to the site by rail has been instrumental in reducing the amount of construction traffic on local roads.

The T5 Agreement

With lessons learned from the many large projects undertaken in the past, BAA wanted to avoid familiar pitfalls associated with large scale construction projects by changing the way in which suppliers and partners worked together. To this end, suppliers on the project worked work under the terms of the T5 Agreement.

The ‘T5 Agreement’ is a legally binding contract between BAA and its key suppliers, unique to the construction industry. Through the agreement, BAA accepts that it carries all of the risk for the construction project.

With the burden of accountability lifted, those working on T5 can innovate and work positively. While traditional arrangements often result in confrontation and high litigation costs if something goes wrong, under the T5 Agreement, a premium is placed on delivering solutions and results.

Many of the T5 suppliers were brought in at the earliest stages of the planning process, working together to identify potential problems and find solutions.

March 2008

BAA Project Director Andrew Wolstenholme is convinced that with its award-winning Occupational Health Centre and Injury and Incident Free (IIF) policy, T5 is the UK’s safest construction site. The project’s first and only fatality a few weeks ago cast a heavy cloud over the work force and they hope not to have any further incidents.

Wolstenholme hopes T5’s stylish design will set a new benchmark in the world of passenger experience. Asked about when the terminal would open, he was very precise. ‘At 4am on the 30th March 2008 – and even the cappuccino will be the right temperature’, he said.