Located on London’s South Bank and busy Queens Walk, the National Theatre in London is one of the United Kingdom’s three most prominent publicly funded performing arts venues, alongside the Royal Shakespeare Company and the Royal Opera House. Internationally, it is known as the National Theatre of Great Britain.

From 1963 until 1976, the company was based at the Old Vic Theatre in Waterloo. The current modern building is located next to the Thames in the South Bank area of Central London. The brutalist building was designed by architects Sir Denys Lasdun and Peter Softley and structural engineers Flint & Neill and contains three stages, which opened individually between 1976 and 1977. The original construction work was carried out by Sir Robert McAlpine.

The theatre has been a Grade II* listed building since 1994.

As part of the NT Futures programme, this refurbishment of Theatre Square, led by landscape architects Gross Max, followed the removal of a temporary theatre, The Shed, a monolithic red box, entirely clad with rough-sawn timber boards.

idverde was awarded the contract for the external works by the Royal National Theatre in South Bank, London, and acted as Principal Contractor.

Our contract works included the design responsibility for reinforced concrete, surface water drainage systems, liquid applied tanking/ waterproofing, and M&E installations. The works also included, new steps and handrails, the refurbishment of existing banner masts, paving, furniture and lighting.

Pop-up supplies for events were installed within the build-ups, and extensive surface water drainage linking to existing ductwork below the basement slab. This required precision drilling to enable the connections.

The works to complete the waterproofing involved exposing the existing membrane through the excavation of sub-base materials, maintaining functionality of the waterproofing to ensure that water did not penetrate the slab. Once exposed the new waterproofing was overlaid and tested in sections in order to open up working areas.

The paving at Theatre Square is in Welsh Blue Pennant and Caithness setts on Steintech mortar; the step details have been realised in white Limestone with tactile specials and Welsh Blue Pennant contrasting nosing. There is a stainless steel Aco brick slot drain to the base of the steps, linear drains, and stainless steel handrail and cycle stands. All paving materials were supplied by the client and all logistics managed by idverde to bring materials in from storage off site.

The project had complex access constraints that had to be navigated. Being a busy theatre in operation, the deliveries needed to be planned and completed either early in the morning or late at night.

The site working area was limited to the finished works, and there were specific loading issues with the basement slab, thereby limiting the amount of materials that could be stored on site. This was resolved by using a storage yard off-site and hauling batches of material into the work areas. The material had to be carefully transported and checked for quality before being placed in the works.

The Theatre was fully operational and hosted numerous National Theatre Live events which required careful planning of the works to reduce noise and allow production crews and vehicles free access to the areas immediately adjacent to our work area. Access to site on some days was completely prohibited owing to filming requirements, so the scheduling of work activities had to be managed to ensure that materials were delivered and available with no loss of productivity, bearing in mind the site constraints and loading capacities of the basement.

A key risk to the project and completion was the quality of client supplied materials and likelihood of having to arrange replacement stone on a long lead. The stone had been stored off-site for over 12 months so the condition was unknown. It was evident on checking quality that this was the case with the Limestone, which required additional stone with a lead-time of 12 weeks with importation from Israel by boat. Critically, a piece of stone damaged in transport needed to be re-procured quickly, so idverde planned air freight to ensure the project completion date was achieved.

At short notice, a red carpet film premiere for Ben Affleck’s Live by Night was scheduled at the British Film Institute, immediately adjacent to the site. Access was required through our works area for the red carpet. We had to accelerate works, complete temporary works and ensure the site was open in a week. This required night-working to minimise impacts to the public and theatre operations and to ensure that the works were fully complete to enable the premiere to go ahead successfully.

Adaptations to the design and bedding were proposed to provide greater efficiency in the project delivery. The site team had to overcome the complications of previous phases delivered by others. For example, jointing in some sections was 18mm wide, where our specification allowed for 10mm. We worked through solutions to provide the best fit and ensure that joints were seamless, while being constrained to a width of 14mm to prevent excessive mortar usages and cost to the client.

It was also important to maintain wheelchair and mobility access to the theatre, so a route was identified and a temporary ramp installed to main as direct an access route as possible.

One of the many challenges was working within a busy public realm environment with work adjacent, above, and below the public. With 9 million visitors a year along the Queen’s Walk, and the busy Christmas Market along the South Bank, we had to ensure that the works were delivered in a way that minimised the risk to our staff, client, members of the public, theatre visitors, and other contractors. We ensured daily briefings covered the key risks to members of the public and highlighted the control measures in place. This ensured to incident or accident during the 20-week programme on the site.

idverde was delighted when, in 2018, its work on this project was rewarded with a British Association of Landscape Industries (BALI) Principal Award in recognition of the excellent standards of hard landscaping construction displayed.