FOI – 2025-000050 Reinforced Autoclaved Aerated Concrete (RAAC) (HTML)

Date received – 17 February 2025 | Date responded – 17 March 2025

Request

In accordance with the Freedom of Information legislation, I would be grateful if you could comply with the following request.

1. Please provide me with full timeline on the work down by NHS Scotland Assure on Reinforced Autoclaved Aerated Concrete (RAAC) in NHS buildings

2. Please outline the "three pilot detailed surveys" done in May 2024, as mentioned in this Scottish Government report to inform a more detailed survey of all NHS buildings with RAAC.

3. Please provide a copy of relevant documents which a) outline the pilot surveys and b) show the outcome of them.

4. Please provide a) a copy of any more detailed surveys done since the pilot surveys in May 2024 and b) where the detailed survey has been completed, a copy of any documentation which confirms the outcome of that survey.

5. If the survey mentioned in Q4 is not complete, please provide me with an update of where the survey is up to.

If my request is too wide in scope or you require any clarity then please do let me know. Thank you in advance for your help in dealing with this request.

Response

I refer to your freedom of information request that we received on 17 February 2025 requesting the following information.

1. Please provide me with full timeline on the work down by NHS Scotland Assure on Reinforced Autoclaved Aerated Concrete (RAAC) in NHS buildings

2. Please outline the "three pilot detailed surveys" done in May 2024, as mentioned in this Scottish Government report to inform a more detailed survey of all NHS buildings with RAAC.

3. Please provide a copy of relevant documents which a) outline the pilot surveys and b) show the outcome of them.

4. Please provide a) a copy of any more detailed surveys done since the pilot surveys in May 2024 and b) where the detailed survey has been completed, a copy of any documentation which confirms the outcome of that survey.

5. If the survey mentioned in Q4 is not complete, please provide me with an update of where the survey is up to.

We have now completed the search of our records and can provide you with the following information:

1. Please provide me with full timeline on the work done by NHS Scotland Assure on Reinforced Autoclaved Aerated Concrete (RAAC) in NHS building

Please refer to the attached document, Appendix 1 – RAAC timeline for the requested information.

2. Please outline the "three pilot detailed surveys" done in May 2024, as mentioned in this Scottish Government report to inform a more detailed survey of all NHS buildings with RAAC.

Discovery inspections carried out across the NHSScotland estate identified buildings that contain Reinforced Autoclaved Aerated Concrete (RAAC). The purpose of the discovery surveys was to ascertain where the RAAC was present, where RAAC was identified, and an initial visual assessment of its condition was completed. This gave the Health Boards (HBs) certainty of where the RAAC was and highlighted any concerns present during the surveys. Remedial actions the HBs were required to implement, along with mitigation measures to be taken, were communicated in the subsequent Discovery Phase Reports. Although the discovery surveys were useful for both locating the RAAC, making an initial visual assessment of the RAAC and advising on remedial action required, there were limitations to the extent of assessment that could be undertaken due to the nature of the discovery surveys. These were as follows:

• Surveys were carried out in areas where access was easily gained in order to prevent any disruption to services and to expedite the surveys.
• The number of penetrations were limited due to site constraints therefore only a small portion of RAAC was observed per property.
• All surveys were non-intrusive in nature to expedite the surveys.
• End bearings were only noted where they could be verified without intrusive investigation.

To meet the requirements of the IStructE guidance, where all RAAC panels and end bearings were investigated and assessed, the next phase of investigation was to establish the overall condition of the RAAC, and the extent of any remedial work required. The investigations considered both the general condition of planks and their bearings.

It was acknowledged that within a live hospital it was not practical to view the soffit of every plank without major disruption to patient care. For this reason, a risk-led approach, based on the following observations, was proposed:

1. Although it would not necessarily be compatible with modern design standards, most RAAC observed during discovery was found to be in good condition.
2. Areas exhibiting distress generally coincided with post installation alterations, or chronic water penetration, or both.
3. In most cases the width of bearings, the presence of reinforcement beyond the support, and the presence of transverse reinforcement within end zones, could not be determined from visual inspection.

To address these issues the following activities have been proposed for relevant properties:

1. Conduct a point cloud survey at roof level to establish the location of penetrations and the magnitude of deflection in each bay.
2. Expose plank soffits for detailed inspection in locations identified by the point cloud survey.
3. Where it is not possible to enhance existing bearings that do not achieve the IStructE requirements, or where the bearings cannot be measured from below, remove roof finishes and ceilings locally to allow bearings and reinforcement to be investigated from above.

To confirm the efficacy of the proposed works a pilot study was conducted at three properties, which are listed below:

• NHS Ayrshire & Arran – A111H - University Hospital Crosshouse, Block 03 - The Lister Building
• NHS Grampian – N101H - Aberdeen Royal Infirmary, Block OA - Phase 1
• NHS Lothian – S116H – Western General Hospital, Block 5S – NTSU Block (Ward 1)

3. Please provide a copy of relevant documents which a) outline the pilot surveys and b) show the outcome of them.

a) Discovery inspections carried out across the NHSScotland estate, identified buildings that contain RAAC. There was no sufficient RAAC observed to determine the overall condition of RAAC present. The next phase of investigation was to establish what overall condition the RAAC was in and whether any remedial work is required. The investigations consider both the general condition of planks and their bearings.

It was acknowledged that within a live hospital it was not practical to view the soffit of every plank without major disruption to patient care. For this reason, a risk-led approach, based on the following observations was proposed:

1. Although it would not necessarily be compatible with modern design standards, most RAAC observed during discovery was found to be in good condition.
2. Areas exhibiting distress generally coincided with post installation alterations, or chronic water penetration, or both.
3. In most cases the width of bearings, the presence of reinforcement beyond the support, and the presence of transverse reinforcement within end zones, could not be determined from visual inspection.

To address these issues the following activities were proposed for relevant properties:

1. Conduct a point cloud survey at roof level to establish the location of penetrations and the magnitude of deflection in each bay.
2. Expose plank soffits for detailed inspection in locations identified by the point cloud survey.
3. Where it is not possible to enhance existing bearings that do not achieve the IStructE requirements, or where the bearings cannot be measured from below, remove roof finishes and ceilings locally to allow bearings and reinforcement to be investigated from above.

To confirm the efficacy of the proposed works a pilot study was conducted at three properties, which are listed below:

• NHS Ayrshire & Arran – A111H - University Hospital Crosshouse, Block 03 - The Lister Building
• NHS Grampian – N101H - Aberdeen Royal Infirmary, Block OA - Phase 1
• NHS Lothian – S116H – Western General Hospital, Block 5S – NTSU Block (Ward 1)

b) Please see attached a copy of the following information in relation to the two pilot surveys completed at NHS Ayrshire & Arran and NHS Lothian:

1. A Heat Map showing the outcome of the Point Cloud Surveys.

• Appendix 2 – University Hospital Crosshouse heatmap.
• Appendix 3 – Western General Hospital heatmap.

2. A Survey Location Overmark showing the locations to be opened and access provided.

• Appendix 4 - University Hospital Crosshouse survey location overmark.
• Appendix 5 – Western General Hospital survey location overmark.

3. A Survey report outlining the outcome of the Detailed Survey.

• Appendix 6 - University Hospital Crosshouse survey report – RAAC Condition Tracker.
• Appendix 7 – Western General Hospital survey report – RAAC Condition Tracker.

4. Please provide a) a copy of any more detailed surveys done since the pilot surveys in May 2024 and b) where the detailed survey has been completed, a copy of any documentation which confirms the outcome of that survey.

Under section 17 of the Freedom of Information Scotland Act, 2002 (FOISA) an organisation does not have to provide that information if it does not hold that information. NHS National Services Scotland (NSS) cannot provide the outcome of the survey, or any follow up actions as per above, as the survey has not yet been completed.

5. If the survey mentioned in Q4 is not complete, please provide me with an update of where the survey is up to.

The Point Cloud survey of the roof at NHS Grampian has been completed but there have been delays in accessing areas to allow the detailed survey of RAAC to commence. NHSScotland Assure are working with NHS Grampian to complete this as soon as practicably possible.

I trust you will find the information of assistance and if you require any further information, please do not hesitate to contact us.

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If you require any further information, please contact the Associate Director Governance and Board Services (Board Secretary) within 40 working days of the date of this correspondence.

Contact

Address

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