Client
Heathrow Airport Limited
Value
£690,000
Sectors & Services
Heathrow Airport is one of the world’s busiest transport hubs and a critical piece of national infrastructure. Terminal 4’s short stay multi-storey car park, opened in 1986 by His Royal Highness Prince Charles and Princess Diana, forms a key gateway for passengers accessing the terminal.
Constructed as an in situ reinforced concrete frame, the structure has been in continuous service for decades under high traffic volumes. Over time, chloride contamination from vehicles tracking de-icing salts into the car park led to reinforcement corrosion and concrete deterioration. Heathrow Airport Limited therefore commissioned a phased refurbishment to preserve the asset, maintain safety, and support long-term operational resilience.
Services undertaken
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Removal of defective concrete
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Grit blasting of exposed reinforcement
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Installation of formwork to beams and columns
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Structural concrete repairs using Weber repair products
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Concrete compressive strength testing
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Removal of existing movement joints
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Installation of new movement joints
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Application of anti-carbonation paint to concrete surfaces
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Phased concrete repair and strengthening works within an operational car park
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Close coordination with client representatives in a live airport environment
Following identification of progressive concrete deterioration, Heathrow Airport Limited issued a competitive tender for remedial works to the Terminal 4 multi-storey car park. CRL successfully secured Phases 1 and 2 and has since been engaged on the structure for more than three years, recently completing Phase 3 of the concrete repair and strengthening programme. The works focused primarily on structural concrete repairs to cross beams and columns, which had been affected by reinforcement corrosion caused by chloride ingress.
A carefully controlled methodology was adopted to maintain structural integrity and keep the car park operational throughout the works. Temporary propping was installed to safely support loads during repairs, allowing defective concrete to be removed without compromising the structure. High pressure water jetting was used to break out deteriorated concrete, a technique selected for its precision and ability to minimise further damage to sound material. Exposed reinforcement was subsequently grit blasted to remove corrosion products and prepare the steel for reinstatement.
Formwork was installed to reinstate the original geometry of beams and columns, and repairs were completed using a Weber concrete repair system, selected for compatibility, durability and performance. Concrete compressive strength testing was undertaken to verify repair quality and compliance with specification. In parallel, existing movement joints were carefully removed and replaced with new joints to reinstate structural movement capability and accommodate thermal and dynamic effects.
The works were delivered in a live airport environment, requiring rigorous planning, coordination and adherence to Heathrow Airport Limited’s exacting health and safety standards. CRL worked closely with client representatives, ensuring open communication and consistent quality control. This collaborative approach enabled Phase 3 to be completed snag-free and to the high standards expected on major infrastructure projects. CRL’s experience in complex concrete repairs and structural repairs UK has positioned the business as a trusted partner for ongoing asset management at Heathrow.
"Working on an operational car park in close proximity to the general public was a real challenge, but with good collaboration between all the stakeholders involved we proved that the works could be carried out safely."
Khalid Rahmany | Project Manager | CRL
Long-term preservation of the Terminal 4 car park was a core objective of the refurbishment works. Following structural repairs, an anti-carbonation paint system was applied to protect repaired and existing concrete surfaces from further carbon dioxide ingress, reducing the risk of future reinforcement corrosion. The use of high pressure water jetting and grit blasting ensured thorough surface preparation, maximising the performance and longevity of both repair materials and protective coatings.
Replacement of movement joints restored the structure’s ability to accommodate movement, reducing stress concentrations and limiting the likelihood of future cracking. Together, these measures significantly enhance durability, resilience and whole-life performance. By addressing the root causes of deterioration and implementing robust protective systems, CRL has helped extend the service life of this critical asset, reduce future maintenance demands, and support Heathrow Airport Limited’s long-term infrastructure strategy.
