Barbican Podium Waterproofing, Drainage and Landscaping Works (Ben Jonson, Breton & Cromwell Highwalk) Phase 2

Concepts

• complete or part construction
• construction work
• barbican podium phase
• waterproofing membrane
• barbican podium waterproofing
• remedial works
• several more phases
• cromwell highwalk
• the podium deck needs
• the damaged waterproofing membrane

Location

London

Description

The Barbican Estate is grade 2 listed with a multitude of uses including an arts centre, 2014 dwellings, exhibition halls, cinemas, restaurants theatres, gallery space and a large conservatory. Designed and constructed in the 1960s and 1970s by architects Chamberlin, Powell and Bon the Barbican Estate represents a prominent example of brutalist architecture. The publicly accessible podium provides a pedestrian only elevated walkway connecting the residential towers, terraces and the Barbican Centre. The existing podium is predominantly made up of brick tiles with areas of defined planting set within the podium. The existing podium deck and waterproofing membrane has become damaged and is leaking into the buildings below including the Exhibition Halls. The City of London, as the owner and manager of the estate, is currently undertaking a large-scale refurbishment of the podium deck. Phase 1 of this refurbishment was completed in 2015, this project will focus on Phase 2; a 18,344sqm area along the northern portion of the estate. Several more phases are expected to be required in order to repair other parts of the podium. An initial feasibility study was undertaken that demonstrated several reasons for this including: • the drainage system; • damage to the waterproofing; • shallow crossfalls; • detailing of the expansion joints. The podium deck needs be taken up to replace and repair the damaged waterproofing membrane. Works were completed on phase 1 in 2015. This project builds on the lessons learned from phase 1 for the area identified as phase 2. Surface refurbishment, replacement of waterproofing membrane, remedial works to drainage infrastructure, and landscaping works to Barbican Podium Phase 2, 1st Priority Zone.

CPV Codes

• 45200000 - Works for complete or part construction and civil engineering work
• 45000000 - Construction work

Indicators

Other Information

The tender will be an open procedure with a likely go live date of September 2024. The tender period will be circa three months with a close return date of end of November 2024. Award of tender is anticipated to be June 2025 with a start on site by September 2025. The anticipated construction duration is circa 24 months with an approximate range of construction value £18million-£20 million. This project is needed, as the existing waterproofing membrane at the podium has deteriorated and can no longer fully protect the concrete structure or spaces below the podium from water ingress. Leaks are already occurring due to this issue and will further escalate until addressed. The water ingress has also caused damage to parts of the podium surface. The completed project will ensure that internal areas in and around the podium are protected from future water ingress. This project will result in improved water management. This means water can be discharged efficiently through the internal drainage system. With the requirement to remove all the of hard standing build up, planting and street furniture to replace the damaged waterproofing membrane there is a unique opportunity to review the design layout and function of the podium. The City of London’s Climate Action Strategy and the Biodiversity Action Plan required a more sustainable approach to the podium. Increased greening, enhanced biodiversity and provision of water attenuation all became integral factors to the project brief. The Barbican podium is the largest public open space located within the City of London. The development of the brief also required an improvement in access, amenity value and safety. This evolution to the brief will provide a more holistic design approach for the podium and future proof it’s use for future generations. Contractors will be expected to demonstrate previous experience in this type of work and value including installation of the Triflex waterproofing membrane system. Interested contractors should contact the person named at I.1 for further information.