Denning Point Tower Refurbishment
Client: EastEnd Homes
Project Value: £4.5m
Brief: Recladding of a 23-storey residential block with non-combustible materials
Sustainability Initiatives: BIM Level 2 recladding project offering a ‘Golden Thread’ of information to the building owners
Denning Point is a 23-storey residential tower in Aldgate, Central London, owned and managed by EastEnd Homes (EeH). The building was originally constructed in the late 1960s and was re-clad with combustible ACM in 2014. Following the Grenfell disaster EeH undertook a risk assessment and subsequently placed a waking watch in the building until the cladding could be removed. ECD Architects were appointed in 2018 to support EeH achieve the safe removal of the cladding and design a safe alternative which complied with updated Building Regulations. In accordance with the recommendations of the Hackitt Review: “Building a Safer Future“ (May 2018) we sought to deliver a ‘Golden thread of information’ through the use of BIM (Building Information Management). This methodology is regarded as key to successful building management of HRRB’s (High Rise Residential Buildings) and as a BIM Level 2 certified practice ECD have the skills necessary to deliver this. Denning Point therefore offers not only a template for the safe removal and replacement of combustible cladding but also best practice in the safe management of high-rise residential buildings.
Following the Grenfell tragedy and subsequent investigation it was clear that the cladding at Denning Point would need to be removed. In order to ensure the swift and safe removal of the combustible cladding as quickly as possible (and thereby remove the waking watch and associated ongoing cost) we procured a cladding removal contractor and this work was completed in October 2019. At the same time, we designed a safe alternative cladding product to meet A1 Fire classification and procured a contractor to deliver this starting on site in February 2020. Whilst the existing cladding had to be removed, both the client and local planning officers were keen to ensure that its replacement closely resembled the current appearance. This led us to propose that the new cladding system should consist of solid aluminum cladding panels, a mineral wool insulation, full fill cavity barriers in horizontal positions and intumescent cavity barriers in vertical positions.
ECD provided a full Architectural service for RIBA Stages 1-7 based on traditional procurement (with CDP) including Principal Designer services (via Keegans). ECD also provided BIM Consultancy services to ensure the delivery of an Asset Information Model. The purpose of the project was to safely replace the existing cladding with a non-combustible alternative which resembled as much as possible the existing aluminium finish. Whilst the non-compbustible insulation results in a slightly thicker build-up the new cladding is virtually identical in appearance and has been accepted by local planning officers on this basis. However, perhaps the most important aspect of this project is the innovation in delivery and the recording of the work through the BIM model. This has required a new collaborative way of working which includes all parties to ensure a consistent approach and effective handover. To assist understanding a process map was developed which incorporates all of the key stakeholders and provides gateway review points for the client with clear obligations on the contractor for the supply of information.
The initial model was generated by undertaking a full point cloud survey of the building with cladding removed. The model is then updated in real-time as the works are undertaken. ECD acts as gatekeeper for the information provided by the contractor and the Clerk of Works provides scrutiny on site to ensure that the works are undertaken in accordance with the design reviewing the model and uploading photographs at key junctions, i.e.: cladding mock-up and fire barriers, etc. The model has also proved to be a useful tool in consultation with the residents with CGI’s generated to explain the visual and physical impact of the works.