Social Housing Decarbonisation Fund Wave 2 Project for a Watford-Based Social Housing Association.

This case study examines Chris West’s role as the Retrofit Coordinator in a Social Housing Decarbonisation Fund (SHDF) Wave 2 project for a Watford-based social housing association. This project, funded by the UK Government, aimed to enhance the energy efficiency of a portfolio of 121 Wimpey No-Fines houses while ensuring compliance with decarbonisation targets and legislative standards. Chris, as the Retrofit Coordinator and PAS 2035 Compliance Lead, worked closely with OVO Energy, the Principal Contractor responsible for the delivery of the retrofit works. Chris was responsible for ensuring the project adhered to the requirements of PAS 2035, coordinated the delivery and design, facilitated communication among all stakeholders, and managed risk throughout the project.

The housing stock in this project comprised of 121 Wimpey No-Fines houses, a post-war construction style known for its unique concrete mix of cement, water, and coarse aggregates. While the construction offered some structural benefits, these properties were highly energy inefficient, prone to heat loss, moisture absorption, and dampness due to the absence of modern insulation. These challenges presented significant difficulties for retrofitting these homes in a cost-effective and compliant way.

Project Approach

Chris’s role involved assessing the retrofit potential of these properties, which required a deep understanding of the Wimpey No-Fines construction style and its limitations. He worked with the client and technical teams to review the energy efficiency of the homes, ensuring a fabric-first approach that prioritised improvements to the building’s fabric before adding more complex measures like photovoltaic (PV) systems. This approach was critical in achieving better energy performance within the project’s funding constraints. Chris led the team in conducting detailed retrofit assessments of each property, using laser devices and Homelife software to collect data, ensuring compliance with RDSAP methodology and PAS 2035 standards. The data revealed that many properties would struggle to meet the target SAP C score with the initially proposed measures, making it evident that a more tailored solution was required. Chris proposed an alternative strategy focused on enhancing the fabric of the properties, maximising insulation measures, and addressing ventilation and damp issues. By reviewing the specification for proposed measures, he was able to demonstrate that a reduced number of measures could deliver a more significant energy improvement. This involved optimising the fabric-first approach, which ultimately saved the client £117K on unnecessary PV installation costs, redirecting these funds to improve additional homes within the project.

Collaboration with Stakeholders

Chris’s coordination efforts were crucial in maintaining effective communication with all stakeholders, including the housing association, the client, and the Principal Contractor. His collaboration ensured that all parties understood the project’s goals and requirements, particularly in the context of the unique challenges posed by the Wimpey No-Fines properties. He also worked with the structural engineer to address concerns about vertical cracking in several properties, ensuring that all defects were documented and managed appropriately. Through regular updates, Chris kept the stakeholders informed about survey progress, defect diagnoses, and any remedial actions required. This communication helped mitigate risks, maintain project timelines, and avoid delays.

Building Pathology & Design

One of the critical aspects of Chris’s role was his deep understanding of building pathology and the application of appropriate retrofit solutions. Understanding the specific challenges posed by Wimpey No-Fines properties, he worked with the client to propose an Insulated Render System (External Wall Insulation), which addressed both the heat loss and damp issues inherent to these homes. By selecting the right system, he helped prevent further structural damage while improving the properties’ energy performance.

Chris also ensured that the design solutions adhered to PAS 2035 principles, balancing resident needs with technical and regulatory compliance. This approach resulted in a cost-effective and environmentally sustainable solution that met the decarbonisation targets without compromising the comfort of the residents.

Risk Management & Project Coordination

Chris’s expertise in risk management ensured that the project stayed on track despite the numerous challenges it faced. By considering all aspects of the retrofit process—from technical solutions to resident concerns—he was able to identify potential risks early and mitigate them. He worked closely with the Principal Contractor to ensure that the retrofit works were carried out safely, efficiently, and in line with PAS 2035 guidelines.