Independent report

RAAC strategic planning: executive summary (accessible version)

Published 12 December 2025

Applies to England

Principle message

The 7 predominantly reinforced autoclaved aerated concrete (RAAC) hospitals (the RAAC 7), as a result of the remediation programme, can remain open beyond 2030. However, the need to deliver the replacement hospitals as soon as feasibly possible remains. The RAAC remediation programme for the RAAC 7 hospitals has and will, once completed, reduce the majority of risks of RAAC plank collapse, protecting patients and staff from the greatest risks. However, between 1% and 6% of RAAC planks are inaccessible and, while plank locations are known and have risk mitigation strategies in place, their inaccessibility and lack of remedial works means such planks will continue to present a risk.

Continuing to operate these hospitals is operationally costly - all 7 are considered to perform poorly and the performance benefits to be realised through the Hospital 2.0 design will not be realised until they are replaced. The need to deliver the replacement hospitals as soon as feasibly possible therefore remains a high priority.

Introduction

This report, commissioned by the Department of Health and Social Care (DHSC) and prepared by Mott MacDonald Ltd, provides an assessment of the 7 NHS hospitals constructed almost entirely of reinforced autoclaved aerated concrete (RAAC) panels and planks. The hospitals - collectively known as the ‘RAAC 7’ - were built between 1970 and 1983 and are now planned for replacement as part of the New Hospital Programme (NHP).

These hospitals were envisaged to be replaced by 2030. This report evaluates the condition of RAAC, infrastructure risks and operational implications of continued use of the RAAC 7 hospitals past 2030. The report considers short term (2030 plus 1 to 3 years), medium term (2030 plus 4 to 6 years) and long term (2030 plus 6 to 10 years) timeframes. This report provides suggested additional remediation and mitigation strategies to support these timeframes.

RAAC is a lightweight concrete material used extensively in mid-20th century construction. It is now known to present significant structural risks, particularly due to poor installation and poor maintenance.

This report identifies that over 80,000 RAAC roof planks are present across the RAAC 7 hospitals, with varying levels of structural remediation installed. While some hospitals are nearing the end of their remediation programmes, others still have works to complete.

This report confirms that, with appropriate mitigation and sustained maintenance, the RAAC 7 hospitals can remain operational beyond 2030. The report notes that without full replacement, the compounded effects of structural and infrastructure degradation significantly elevates operational and clinical risks.

DHSC set 4 objectives for this study. The report has been structured to respond to each of these objectives. The summary of findings against these 4 objectives is as follows.

1. Remaining expected life

Aim of the objective

Determine the remaining expected life of each hospital site and area-by-area breakdown.

Summary response

The RAAC 7 hospitals have undergone significant RAAC remediation comprising full-span or end-bearing support.

Despite best efforts, RAAC risks are expected to remain across each site with instances of planks being deemed inaccessible for remediation. This varies for each site and has been identified, typically 1% but in one instance up to 6%. This is not unexpected given the complexity of RAAC remediation within live hospitals and the need to balance these works with maintaining clinical operations.

Critical to risk mitigation is ongoing investment in the maintenance of infrastructure - in particular, the mechanical infrastructure that can have a direct impact on RAAC structures (for example, leaks).

With ongoing management and maintenance, it is expected that RAAC planks and panels may technically remain serviceable beyond 2030 and in the long term (2030 plus 10 years). However, practically costs and risks are expected to increase as RAAC planks and panels are retained beyond 2030 and in the medium term (2030 plus 6 years).

The assumptions for RAAC planks assume no change in environmental condition or changes in our understanding of RAAC occurs, and that fabric repairs and infrastructure maintenance to prevent leaks continues.

Trusts will need to continue to risk assess RAAC planks and determine appropriate measures to ensure risks remain as-low-as-reasonably-practicable, particularly for inaccessible planks and if programmes extend.

It is recommended that the replacement of the RAAC hospitals continues as a priority.

This is covered in detail in section 5 of the report, published alongside this executive summary on the RAAC strategic planning: assessment of the RAAC 7 hospitals page.

2. Additional mitigation works

Aim of the objective

Identify additional mitigation works to extend the safe use of the hospitals and associated costs.

Summary response

Additional mitigation focuses on maintaining RAAC within a dry environment. This includes roof repairs combined with continued management surveying in the short to long term (2030 plus 1 to 10 years).

Given the age of the buildings, further surveying and isolated repairs of the primary structural frames may also be required in the medium to long term (2030 plus 6 to 10 years).

Ongoing mechanical and electrical infrastructure repair, maintenance and replacement will be required. As the hospitals age, the need to replace infrastructure will increase with time, particularly with regards to mechanical infrastructure.

Estimated annual costs per site range from [redacted] for RAAC remediation in the long term (2030 plus 6 to 10 years).

This is covered in detail in section 6 of the report, published alongside this executive summary on the RAAC strategic planning: assessment of the RAAC 7 hospitals page.

3. Clinical operational impacts

Aim of the objective

Assess the clinical impacts of opening replacement hospital after 2030 or past the expected end of life.

Summary response

Post-remediation, the RAAC 7 hospitals will generally be in similar operational position to other hospitals of similar age, configuration and size, yet with continued RAAC related challenges.

The RAAC remedial works have in some instances compromised clinical spaces and ongoing RAAC related survey and remediation works will have an ongoing clinical disruption.

The presence of un-remediated, inaccessible panels continues to present an ongoing risk (as noted in objective 1 above), alongside ongoing infrastructure risks which may also exacerbate RAAC related risks.

Facilities will also be increasingly out-of-step with modern clinical practice and an ever more acutely ill patient cohort. Any further delay to the replacement of these facilities will delay and compromise the benefits realised by the NHP - the programme business case predicted a benefit cost ratio of more than 3:1 and it is therefore paramount that they are replaced without further delay.

This is covered in detail in section 7 of the report, published alongside this executive summary on the RAAC strategic planning: assessment of the RAAC 7 hospitals page.

4. Options for phased approach for replacement

Aim of the objective

Assess possible options around phased replacement to minimise RAAC and backlog risks.

Summary response

Phased redevelopment of the RAAC 7 hospitals is theoretically viable. Departments such as outpatients, pathology, central sterile service department (CSSD) and catering are considered feasible for standalone delivery. However, services with critical adjacencies - such as intensive care unit (ICU), theatres, urgent and emergency care (UEC) and so on - make phasing challenging.

To be viable, a phased redevelopment approach would need to deliver facilities faster than the current NHP plans or timeline.

Re-evaluating the existing NHP plans to consider an alternate phased approach would likely be disruptive and risk delaying overall delivery, potentially negating the benefits of phasing.

Nonetheless, if delivery of the new hospitals under the NHP is delayed beyond the current construction timeline set out in in the NHP plan for implementation (construction expected to start between 2027 and 2029), it would be appropriate to reconsider phasing opportunities.

This is covered in detail in section 8 of the report, published alongside this executive summary on the RAAC strategic planning: assessment of the RAAC 7 hospitals page.

Main messages

The main messages contained in the report are:

• RAAC remediation has stabilised the risk - but not eliminated it. The hospitals can operate safely to 2030 and beyond - but with conditions
• mechanical infrastructure is a critical weakness
• significant investment has already been given to reduce risks
• delays to hospital replacement increase cost and risk
• the hospital trusts have responded to considerable challenges but see the new hospitals as the light at the end of the tunnel
• remediation is not a substitute for replacement
• delivery of the new hospitals should be prioritised over phasing, but this should be re-evaluated if delays are expected