Edinburgh Airport expansion

The challenge: invisible infrastructure and high security

With its century-long history of development, the site came with some big challenges. The building footprint was heavily serviced with gas, high and low-voltage electricity supplies, domestic water supplies, surface and foul water drainage. Not to mention the fibre optic data cabling for air traffic control: critical to flight operations.

But many of these services were impossible to trace before the project. Many simply couldn’t be diverted. Many more were uncovered during construction. All were vital and many needed to be upgraded to enable modern airport operations.

One of BAM’s first tasks was to install piled foundations between these services. And to continue dealing with this hugely complex web of services as it emerged over the course of the project.

The security aspects of the project were also, rightly, very challenging. Much of the work had to be carried out airside: where all people and materials had to be carefully screened and monitored and all construction methodologies needed to be reviewed and approved as suitable by the airport operations team. 

The BAM solution: constant adaption and modern methods

The new building had to be effectively constructed around an existing airside link bridge, with the departure and arrivals halls staying open throughout the work. The existing link bridge was removed once the new building was complete and an alternative route could be provided.

To minimise disruption to travellers, BAM had to maintain live, but constantly changing routes through the site. The on-site team was working beneath, over and around live sections of arrivals and departure halls and tunnels. And many safety-critical tasks could only be completed at night.

As the work progressed, BAM and the airport management developed and implemented different routes for people to move through the terminal: even when the roof was being taken off to drop in columns for new structures.

The Gogar Burn – an ancient stream – runs through the site. Lifting three prefabricated 30 tonne link bridges over the Burn eliminated the health and safety challenges of working at height over a watercourse and compressed what could have been a long and disruptive on-site build to just three days.

BAM also used precast lift sections to install the eight new lifts in the terminal complex.

Digital tools were used throughout the design and construction, using point cloud surveys of existing structures and 3D models of the new building elements to make sure new elements could fit in the available space. This in turn helped inform the construction methodologies to ensure everything could be built safely within the site constraints.

Throughout the project, supply chain was key, especially given the security and logistical challenges. BAM worked in partnership with the airport management team and in-house surveyors to choose and validate subcontractors.

The results: a 21st century transport hub

Given the complex nature of the site and the significant unknowns when it came to utilities and services, the timescales and scope of the project did expand significantly.

Over the course of the project, BAM accommodated and delivered some 1,000 variations and extensions to works: all agreed as essential by the client and many arising because there just wasn’t enough information available about the site before BAM started work, so issues couldn’t have been foreseen by anyone.

That meant agreeing a constantly changing programme, with a very diverse set of stakeholders, each with different priorities. For example, as the airport agreed and let franchise space with tenants for areas in the new terminal building, this changed the design requirements for these areas.

The phased handover – in five key stages - kept everyone focused on deadlines. The site was eventually running 24 hours a day, six or seven days a week for nine months, as pressure to maintain progress was intense. 

From enabling to fit-out, BAM and its trusted supply chain successfully delivered new domestic and international arrivals facilities including baggage reclaim and border control, new retail and food outlets, and expanded lounge space along with new office accommodation.

The new link bridges and stair nodes meant it was now possible to connect to more modern and larger aircraft stands. And an extension to the south-east pier provided extra departure/arrival gates.

Thanks partly to modular off-site construction, key elements of the project were delivered in days rather than months.

The airport owners were delighted with the finished project: a flagship for Scotland’s economic growth.