Get retrofit right

Martin Hitchin of REHAU UK highlights how retrofitting window and door frames, alongside the necessary supply chain collaboration, is a vital component of improving thermal performance and meeting net zero targets across the sector.

The residential sector accounts for approximately 18% of the UK’s carbon emissions, with social landlords owning 17% of the nation’s housing stock. This means social housing accounts for roughly 3% of the nation’s carbon footprint. Yet this is not the only concern – homes in the 1980s were not built to modern thermal performance and sustainability standards. Despite these concerns, the social housing sector must still meet legally mandatory UK decarbonisation benchmarks, including a 78% reduction in emissions by 2035 and net zero by 2050.

Additionally, the UK’s Clean Growth Strategy requires social housing providers to attain Energy Performance Certificate C for rented properties by 2035, or 2030 for ‘fuel poor’ households. This legislative landscape presents clear obstacles for the social housing sector.

Seeing a Path Forward

Despite this, funding is available to help progress the sector’s sustainability goals, including the £1.5bn awarded in 2022 through the Government’s Social Housing Decarbonisation Fund, which was bolstered by an additional £1.25bn in 2023. Support can also come from the Home Upgrade Grant, the Public Sector Decarbonisation Scheme and the Warm Homes Plan.

Social housing stakeholders must ask themselves what cost-effective components will have the greatest impact on a property’s thermal
performance. REHAU’s latest white paper, ‘Retrofit Right – Making Social Housing More Energy-Efficient’, highlights how windows and door systems, as prominent sources of heat loss, play a crucial role in decarbonising existing social housing stock.

Carrying out ‘medium retrofits’ – fitting high-quality frames on existing homes – can markedly and cost-effectively improve thermal performance across social housing portfolios. However, this is reliant on an informed component specification process, which is key to ensuring existing funding works as hard as possible.

The report goes on to explore the thermal efficiency, noise attenuation, security, and ventilation standards to consider when specifying new frames. It advises specifiers to leverage third-party expertise for retrofitting projects to bridge knowledge gaps and ease workload burdens as construction activity increases.

Specifically, it emphasises that ensuring high-quality supply chains, including engaging installers and fabricators working to third-party certifications, is crucial for effective retrofitting works. Adherence to these accreditations and standards demonstrates to local authority and social housing stakeholders that projects will be completed on time, within budget, and with high-quality components.

Pursuing Polymer

In an environment where energy efficiency is crucial, the thermal performance of polymer frames stands out as a way to reduce carbon footprints. PVCu, the UK’s most popular material for windows and doors due to its durability, affordability, and lightweight properties, has become one of the most sustainable construction materials available. Innovations in frame design have significantly improved the thermal performance of polymer systems, while also enhancing solar gain, condensation reduction, airtightness, indoor comfort and overall security.

PVCu frames can also now achieve the Building Research Establishment’s ‘A’ rating under the Green Guide to Specification, a key resource for selecting construction materials based on their environmental impact.

Polymer’s sustainability is further enhanced by its recycling capabilities, as it can be recycled up to 10 times before showing signs of degradation. Given the average lifespan of a PVCu frame is 35 years, combined with appropriate recycling infrastructure, polymer is a sustainable, long-lasting material.

Going Beyond the Point of Purchase

Material considerations are key, but social housing stakeholders should not solely focus on point of purchase when selecting window and door systems for retrofitting works. The ongoing performance and adaptability of specific frames are crucial for ensuring energy-efficient properties and reducing building stock emissions. Local Authority and Housing association maintenance teams play an important role in this, as explored in ‘Retrofit Right’.

In the event of further installation work including repairs or installing frame accessories, it is vital this can be completed quickly and cost-effectively. Indeed, these ‘data-driven’ digital technologies can streamline remedial works. With maintenance teams increasingly time-poor and overstretched, a protracted process of communication, property inspections, and material procurement will only exacerbate the situation. Consequently, ways of streamlining this process are likely to become of increasing interest to social housing project stakeholders as more upgrading works are greenlit.

Integrated into window and door systems, technologies such as digital ID cards and apps can offer a way forward. Quick access to key data through these innovations can provide maintenance teams with the information required while greatly reducing the need for time-consuming inspection or measurement appointments. Instead, expert frame specialists can be quickly contacted via an app, significantly shortening the process and allowing housing associations and local authorities to save money and resources by reducing the number of visits to affected properties. REHAU, for example, has developed a new digital technology that encompasses the complete life cycle of a window or door, thereby providing an important link to the “Golden Thread” within the Building Safety Act 2022.

Future Concerns, Current Action

Upgrading existing social housing stock is crucial to meet net zero and energy efficiency targets. With available funding and looming decarbonisation deadlines, the need for action is urgent. Local authority and housing association stakeholders must plan retrofits carefully, ensuring each step of specific projects is well-informed and cost-effective.

Replacing key components such as windows and doors is highly technical and requires adherence to strict regulations and performance criteria. As such, specifiers are advised to leverage third-party expertise for retrofitting projects to help bridge knowledge gaps and ease workload burdens for under-pressure local authority and housing association teams with stretched budgets. This combination of sector knowledge, social housing project experience, and access to high-quality fabricator and authorised partner installer networks is essential for sourcing components that can improve the thermal efficiency of social homes.

Martin Hitchin is CEO at REHAU UK

Scan the QR Code to download REHAU’s latest report: Retrofit Right – Making Social Housing More Energy-Efficient