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The medieval castle and prison complex Oxford Castle Quarter offers a rich historical experience in Oxford. It consists of the Oxford Castle, built in the 11th century, the luxurious Malmaison Hotel, and a mix of modern residential and commercial developments.

The B-Wing is known for its contemporary design, which stands out from the historical buildings. This residential building comprises of 33 apartments, spanning three levels in the north building and two upper levels in the south building, with the top-floor apartments offering duplex living.

The North and South blocks maintain a height below 18m, but the presence of combustible materials on all elevations required a full external wall assessment. Therefore, our team evaluated the building's external wall construction to assess the extent of combustible elements and evaluate the risk these hazardous materials would pose to the life of its occupants.

To carry out a full Fire Risk Appraisal of External Walls (FRAEW), our team conducted a holistic assessment of the risk associated with external fire spread in the context of the use, occupancy, façade configuration and fire safety arrangements of the building. This helps provide a more pragmatic and risk-proportionate approach, and it categorizes the risk on a scale ranging from Low Risk to Medium Risk (Tolerable or Non-Tolerable) to High Risk. With this framework in mind, the investigation into B-Wing's external walls system (EWS) evolved over three comprehensive stages:

  • Stage 1: Desktop Assessment: The first stage involved a meticulous examination of the external wall design. It was the initial step in understanding the potential risks posed by the wall construction.
  • Stage 2: On-Site Intrusion: The second stage took the investigation to the actual site. Here, an intrusive examination of the external walls was carried out. This hands-on approach allowed for a more thorough understanding of the materials and their implications.
  • Stage 3: Risk Appraisal: The third and final stage encompassed a holistic appraisal of risk factors. It extended beyond the walls themselves and included a visit to the communal and external surrounding areas. This comprehensive evaluation factored in façade configuration, fire safety measures, and potential fire hazards.

Following these stages of the investigation, it became clear that the overall risk was deemed a medium risk, necessitating remediation work to reduce the items that were posing a risk.

A detailed list of remediation works was compiled, with the primary aim of transitioning from a Medium to a Low-Risk designation. Subsequently, our team was assigned to review the proposals from the contractor and closely monitor the works on-site. The objective was simple yet paramount – to reduce the risk to a level where the building could achieve an EWS1 B1 rating in the EWS1 form. In principle, this signifies that the presence of combustible materials in the external wall no longer posed a significant fire risk, and further remedial actions were not necessary.

Home for the first Oxford University, Oxford Castle Quarter, our team developed a Fire Risk Appraisal of External Walls to meet the client’s need and ensure safer construction methods.

Project Details

Client

Westgate Oxford Alliance GP

Project Location

Oxford, UK

Project Size

4 Storeys

Timeline

Feb 2024

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