Public Finance Initiatives (PFI) have become instrumental in funding and delivering NHS facilities, including multi-storey car parks within healthcare estates. However, as many of these will be handed back to local authority control in the forthcoming years, asset condition is now at the forefront of any transference. The successful handover of these projects demands a thorough assessment process, particularly focusing on waterproofing and surfacing solutions tailored to the unique needs of any healthcare estate parking provision. In this blog, we explore the intricacies of PFI assessments within healthcare estates and underscore the significance of robust multi-storey car park waterproofing and surfacing practices. 

Understanding PFI Assessments: Public Finance Initiatives have reshaped the landscape of healthcare infrastructure development in the UK, facilitating the construction and management of vital facilities such as hospitals and medical centres. These partnerships between the public and private sectors allow for the construction, operation, and maintenance of public assets. However, before a multi-storey car park can be handed over to the public body, a comprehensive PFI assessment is conducted to ensure adherence to quality standards, safety regulations and operational efficiency.

Key Components of PFI Assessments

1.    Structural Integrity: Assessments focus on the structural stability of the multi-storey car park, evaluating its ability to withstand static and dynamic vehicle loadings, and environmental factors.

2.    Safety Standards: Compliance with safety regulations, including fire risk assessments, emergency exits and lighting, is thoroughly scrutinised.

3.    Functional Efficiency: The functionality of the car park, such as traffic flow, signage, and accessibility for disabled users, is assessed to ensure optimal usability.

4.    Long-Term Maintenance: Provisions for ongoing maintenance and repairs via a life care plan, are evaluated to guarantee the longevity of the infrastructure.

5.    Waterproofing and Surfacing: Perhaps one of the most critical aspects of PFI assessments for multi-storey car parks is the examination of waterproofing, surfacing and protection systems.

Significance of Waterproofing and Surfacing

Waterproofing and surfacing play a pivotal role in the durability and safety of multi-storey car parks, especially in the UK's unpredictable climate. Here’s why:

1.    Protection Against Water Damage: The catalyst for the deterioration processes in reinforced concrete structures is water, without which, these processes essentially discontinue. Water can enter a parking structure in many ways including ineffective joints, drainage systems, design defects and damaged elements. Effective deck and ramp waterproofing systems are the primary defence against ingress, protecting against structural deterioration and safety hazards over time. 

2.    Protection against chloride ingress: Regardless of whether the frame is steel or concrete, nearly all permanent car park decks are constructed of concrete reinforced with steel. Chlorides from de-icing road salts are driven in by vehicles and when dissolved in water, can migrate to the steel reinforcement, particularly in the absence of a waterproofing membrane or where the concrete is cracked. When chloride ions reach the steel surface, in the presence of oxygen and water, they break down the protective, passive film leading to localised corrosion (rusting). 

3.    Protection against carbonation: Carbonation is the process of carbon dioxide (CO2) entering concrete and reacting with pore water. The resulting acidic compounds reduce the natural alkalinity of concrete, depassivating the steel’s protective layer and again, in the presence of oxygen and water, corrosion occurs. Whether chloride or carbonation-based corrosion, left unchecked the steel reinforcement’s strength will reduce over time, jeopardizing the structural integrity of the car park.  

4.    Ability for dynamic crack bridging: Similar in nature to bridges, multi-storey car parks are dynamic (mobile) structures, designed to deal with the passage of vehicles and all weather conditions including seasonal, temperature-related expansion and contraction. Such movement can lead to cracks forming in the concrete fabric, providing a direct route for water, chlorides and carbon dioxide to the embedded steel reinforcement. An essential step to protecting against such dynamic cracking is a waterproofing system’s ability to ‘crack bridge.’ Understanding the ongoing movement of the multi-storey car park and specifying systems suitably certified under EN 1504-2 ensures a long term approach to crack bridging and structural protection.

5.    Enhanced safety: Appropriate anti-skid surfacing reduces the risk of skids, slips, trips and falls, particularly during wet and icy weather conditions, ensuring the safety of pedestrians and vehicles alike. Contrasting line markings, directional signage and pedestrian walkways can ensure users can navigate the facility efficiently and safely.  

6.    Longevity of infrastructure: High-quality waterproofing and surfacing materials contribute to the longevity of the car park, reducing the disruption and costs associated with frequent repairs and maintenance, whilst improving the aesthetics and user’s overall experience. 

7.    Sustainable solutions: Considered refurbishment methods that recoat (overlay) existing materials avoids wasteful stripping and disposal of existing surfaces. A cost-effective and more sustainable waterproofing method aligns with environmental standards and reduces the carbon footprint of the infrastructure.

Challenges and Solutions

Despite the importance of waterproofing and surfacing, challenges may arise during the assessment and handover process. These challenges include:

• Identifying the most suitable waterproofing systems and surfacing materials
• Ensuring compatibility with existing infrastructure and architectural design
• Ensuring quality and durability

To address these challenges, collaboration between project stakeholders, including engineers, surveyors, contractors, and materials suppliers, is essential. Additionally, leveraging innovative technologies and conducting thorough site inspections can help identify potential issues and implement effective solutions.

Conclusion

In the realm of PFI assessments and multi-storey car park handovers, waterproofing and surfacing emerge as critical components that demand careful consideration. 

Triflex understand multi-storey car park structures. Benefit from our 25 years expertise in protecting these unique structures, with BBA certified, dynamic crack bridging systems that rapidly cure, minimising disruption and provide a robust solution for long term protection.

Take advantage of our free services from consultation and free of charge condition surveys to bespoke project specification proposals and warrantied solutions.