PROJECT PROFILE

Scottish Water RAAC Strengthening Works

INTRODUCTION

Scottish Water identified areas of Reinforced Autoclaved Aerated Concrete (RAAC) within an operational building. Following structural assessments, the decision was made to strengthen the existing RAAC panels in situ rather than undertake full removal. Starfish Construction was appointed as Principal Contractor due to our proven track record in RAAC remediation and our ability to manage complex strengthening works in live and high risk environments.

ROOF RAAC STRENGTHENING

Expertise in commercial RAAC management

Working in an occupied and business-critical building required a controlled and highly coordinated approach. Our team developed a safe system of work that protected the client’s operations, maintained continuity of essential services and delivered full compliance with Scottish Water’s stringent technical and safety standards.

Crane positioning steel onto a industrial roof

The works involved exposing the RAAC panels, implementing a strengthening system and restoring the area to a safe and functional condition. Key deliverables included: Acting as Principal Contractor and managing all site operations, H&S, and coordination with Scottish Water. Temporary works design and controlled access strategy beneath RAAC-affected zones. Careful removal of ceiling finishes to expose panels. Installation of a strengthening system comprising: Steel supportwork fixed to load-bearing structural elements. Timber joists are installed to distribute loads across weakened panel areas. Protection and temporary rerouting of M&E services impacted by works. Ongoing engagement with the structural engineer to validate installation stages. Full QA documentation, including Procore-recorded progress photos, materials certificates, and installation records. Final engineer approval and handover pack confirming strengthened RAAC system.

SUCCESSFUL PROJECT OUTCOME

RAAC strengthening solution

The strengthening solution delivered a safe, durable, and efficient remediation strategy that avoided the disruption and cost associated with full RAAC removal. All works were completed on programme, within the client’s operational constraints, and with zero incidents.

The project demonstrates Starfish Construction’s capability in delivering RAAC strengthening within challenging live environments, supported by strong temporary works design, engineered solutions and clear quality assurance. Our experience allows us to give clients confidence that RAAC affected buildings can be safely strengthened, reinstated, and kept operational throughout.

When RAAC is discovered in a roof structure, the first step is a thorough survey to assess material integrity and identify any structural weaknesses. In this project, the best solution was to restrengthen rather than remove.

This project reflects the strengths of our approach, where engineered solutions, careful temporary works design and disciplined site coordination come together to deliver RAAC strengthening safely within a live, business-critical environment.

By protecting operations, maintaining essential services and upholding the highest technical and safety standards, we demonstrated that RAAC affected buildings can be strengthened in situ with confidence, control and minimal disruption.

JOE SHERIDAN, ASSOCIATE DIRECTOR, PROJECTS SCOTLAND, AT STARFISH CONSTRUCTION