INCA Case Study: Enfield Refurbishment Project

The London Borough of Enfield (LBE) alongside The Greater London Authority (GLA) embarked on a mission to tackle energy inefficiency and improve living conditions in 44 semi-detached 1930s solid brick-built properties suffering from dampness and condensation, harbouring an invisible menace that greatly impacted the health and well-being of the residents. LBE carried out a review of their properties to identify homes suffering from poor energy performance resulting in residents incurring higher energy bills and these properties were recognised.

Determined to find a solution LBE faced challenges in finding effective resolutions for these issues. They recognised the pressing need for effective measures that would not only tackle the existing issues but also pave the way for a better future. Remedial measures like vent installations unintentionally created draughts and compounded the difficulties in treating the properties. Realising the significance of this prevalent housing archetype, it was clear that a more comprehensive and innovative approach was required. Therefore, this project became a beacon of hope, providing a valuable reference for large-scale improvements.

First, Osborne needed to understand LBE’s aspirations for this project, fully understanding their expectation is key to developing a successful design. Secondly, Osborne spoke with the residents, to try and understand what’s most important when developing the design, how their home would look after the installation of the system was top on the list, followed closely by how much space would the system take from their home. Allowing residents to input into the design is vital to maintaining a working relationship throughout the project, ensuring continued regular engagement potentially reduces residents from withdrawing from the programme.

Throughout the design process Osborne and LBE held several group presentations with residents to discuss the design to retrofit each home. During the engagement Osborne tried to debunk the mystery and complexities which surround decarbonisation and learned a bespoke resident engagement process was needed and will work alongside partnering contractors to develop this for future projects.

Following notice to proceed with delivery LBE carried out an internal finance review which resulted in the contract budget reducing by 50%. Therefore, the number of properties which could be delivered reduced to 10 and the approach to energy efficiency delivery had to change.

To maximise on performance, Osborne reviewed all system components as well as fabric solutions and looked at more traditional options to insulate the fabric of the building that aligned with Osborne planning pre-application maintaining the Permitted Development status. The fabric solution chosen was Soltherm EWI with a brick slip weathering finish, coupled with triple glazed casement windows and high-performance entrance doors.

Osborne also looked at ways to reduce the need to occupy the storage areas within the home with system components. By utilising a single M&E provider they had the option to reduce the system components while maintaining the performance targets.

All the above solution changes we’re designed to maintain the projects permitted development status.

When tackling a whole house retrofit, working in partnership with experienced specialists is key. With the collaboration between Osborne Property Services Ltd Carbon Neutral Solutions and Bow Tie Construction, the Soltherm Deco P Brick-ID system was implemented across all 10 properties. An impressive 1000m² of External Wall Insulation (EWI) and Deco X Silicone below the Damp-Proof Course (DPC) were applied, revolutionising the thermal performance of the buildings. In addition to this, several other measures were implemented, including the installation of solar PV systems, air source heat pumps, mechanical ventilation with heat recovery (MVHR), and upgrading windows, doors, and loft insulation. These multiple measures worked in harmony, delivering unmatched thermal efficiency, and reducing heating costs for residents.

The true beauty of the Deco system lay in its ability to replicate the original façade, while surpassing the rigorous requirements of Building Regulations. With an exceptional U-value of 0.18, these homes boasted thermal performance that exceeded all expectations. Meticulous design played a pivotal role in minimising heat loss at critical junctions, such as windows and doors, eliminating those dreaded cold bridges that once plagued the residents. The comprehensive approach extended to loft insulation and the replacement of old windows and doors with cutting-edge triple-glazed alternatives.

Of course, no great journey is without its challenges. Throughout the project, there were various challenges that were encountered and overcome with dedication and expertise. The installation process required careful navigation around existing conduits, vents, and ducting at the rear of the properties. This demanded meticulous coordination or, in some cases, removal and consolidation to minimise complexity and disruption. Thorough detailing was employed to ensure a seamless integration of the external vent box housing the MVHR system, as well as around the windows and doors, meticulously replicating the original façade’s aesthetics.

The successful completion of this project establishes it as a shining example of proper EWI installation and best practices. The expertise and attention to detail demonstrated by the team are invaluable resources that will contribute to future Soltherm training offerings. As a result of this project, the ten semi-detached properties in LBE have undergone a remarkable transformation, addressed their energy inefficiency and significantly improved the living conditions for the residents.

Achieving an average reduction of 3 Tonnes in CO₂ emissions, annually, for each property and an average decrease of 8,099kWh per year in space heating, also achieving an EPC rating of B.

Through the dedication and vision of LBE, GLA, Osborne Property Services Ltd Carbon Neutral Solutions, Bow Tie Construction, Osmosis ACD Ltd, Pellings, Turner & Townsend, Energiesprong UK and Soltherm External Insulations, these homes have undergone a remarkable metamorphosis. They were no longer burdened by energy inefficiency and dampness but instead stood tall as testaments to the power of innovation and collaboration. The lives of their residents have been forever changed, as they step into a brighter, more comfortable future.