Understanding Reinforced Autoclaved Aerated Concrete (‘RAAC’)
Reinforced Autoclaved Aerated Concrete (‘RAAC’) is a lightweight, precast concrete material that was commonly used in UK construction between the 1950s and 1990s. Manufactured in planks or panels, RAAC was particularly popular in public and commercial buildings due to its affordability, thermal efficiency, and ease of installation.
However, RAAC has a typical design life of around 30 years. As a result, many buildings containing RAAC have now exceeded this lifespan, leading to increasing concerns over structural integrity and safety.
In recent years, the risks associated with ageing RAAC have come under renewed scrutiny. A notable example is the closure of Denburn Health Centre in Aberdeen in September 2023, after RAAC-related defects were discovered in the roof structure.
Why RAAC is a concern
Unlike traditional concrete, RAAC lacks coarse aggregate, making it significantly weaker and more porous. Over time, this can result in cracking, water ingress, and even sudden structural failure if not identified and addressed.
The potential safety implications are serious, particularly in older buildings where routine inspections may not have included RAAC-specific assessments. Where RAAC is found to be in poor condition, urgent remedial work may be required.
Identifying RAAC is Commercial Properties
Determining whether RAAC is present in a commercial property can be complex. Because the material is often hidden within the fabric of the building, visual inspections are rarely sufficient.
The first step is to review construction records, architectural drawings, or building specifications from the relevant period. Property owners and tenants should consider engaging a qualified structural engineer or building surveyor to carry out a detailed inspection.
Failure to assess a building’s RAAC risk may lead to significant legal and financial consequences. In leased premises, landlords should exercise caution when arranging inspections, as tenants are legally entitled to “quiet enjoyment” of the premises.
Before entering the property, landlords must:
- Review the lease terms carefully to confirm inspection rights.
- Determine whether there are any restrictions on exercising those rights.
- Seek legal advice if there is uncertainty around access or obligations.
- Where no inspection clause exists, landlords may need to wait until the lease expires or obtain the tenant’s consent before carrying out investigations.
Who is Responsible for RAAC?
Responsibility for addressing RAAC-related issues in commercial leases depends on several factors, primarily the terms of the lease and the nature of the defect. Key considerations include whether the duty to repair and maintain the premises falls on the landlord or tenant, who is responsible for maintaining and repairing the structure and common parts, and, in the case of multi-occupied buildings, whether RAAC is present in communal areas.
Determining liability for the costs of repair or replacement is also crucial. Importantly, the mere presence of RAAC does not automatically trigger a repair obligation; action is typically only required when the RAAC is found to be defective, unsafe, or in need of remediation.
Legal Implications of RAAC Defects
The legal and financial implications of RAAC defects can be considerable. Addressing structural concerns often involves significant expenditure, making it essential for all parties to have a clear understanding of their liabilities. Determining responsibility requires distinguishing between different types of defects:
Latent defects – Hidden issues resulting from poor design, materials, or workmanship.
Inherent defects – Flaws embedded within the building from the time of its original construction.
Extraordinary repairs – Substantial works that go beyond routine maintenance.
Under general legal principles, landlords are typically responsible for extraordinary repairs. However, under full repairing and insuring (FRI) leases, tenants may bear this responsibility, depending on the precise wording of the lease. Many FRI leases include exclusions for latent or inherent defects, meaning tenants may not be liable for issues arising from the original construction of the building.
Each lease must be carefully reviewed to determine:
- The extent of the tenant’s repairing obligations;
- Any exceptions or exclusions relating to structural defects;
- The definition of “repair” and whether it encompasses replacement or full reconstruction.
Once liability is established, the party responsible may be served with formal notice to carry out remedial works. Failure to comply could give rise to a claim for breach of lease, damages, or other legal remedies.
Steps for Landlords and Tenants – and Why They Matter
RAAC presents a growing risk across the UK’s commercial property landscape, particularly in buildings constructed or refurbished between the 1950s and 1990s. It is vital for both landlords and tenants to act promptly to assess their legal responsibilities, understand their lease terms, and take the necessary steps to ensure safety and compliance.
Both parties should seek legal advice at the earliest opportunity to clarify their obligations and minimise risk. Proactive management and a clear understanding of lease terms are essential to avoid costly disputes and ensure compliance with safety regulations.
If you wish to discuss any of the above, please contact our Dispute Resolution Team below or call us on 01702 338338.
