Fire safety and design  

Case study: Wilmcote House

When old council buildings are in need of maintenance, it is often not feasible to relocate residents; one of the most economical and least disruptive approaches is refurbishment, equipping the building with the necessary resources to provide safe and efficient housing for long-term occupation.

Wilmcote House, located in Portsmouth, is an example of this endeavour. Constructed in 1968, Wilmcote House was built as a high-density post-war housing estate, and the accommodation remains a prominent feature of Britain’s urban landscape. This year the three 11-storey residential blocks have been transformed into comfortable contemporary dwellings without the need to relocate inhabitants. Completed in four years, the development has reduced inhabitants’ fuel costs, improved their standard of living and is the largest EnerPHiT standard scheme delivered with occupants in-situ.

All image credits: Rockwool.

Designed by EDC Architects, the building provides sustainable and affordable housing for Portsmouth City Council. Since it’s completion, the residency has won numerous awards including the RICS Awards- Design Through Innovation Category, 2018 and the Constructing Excellence Awards-Sustainability category 2018.

The regeneration initiative began when research from the London School of Economics and Political Science (LSE) encouraged the renovation of the building to address the concerns regarding tenant health, fuel poverty and wasteful energy leakage. In light of LSE’s research, the aim of the renovation was to lower the demand for heating within the accommodation by 90%, increase occupants’ comfort levels, and extend the construction’s life by 30 years.

Following the programme, 100 three-bedroom maisonettes, two three-bedroom flats, two one-bedroom flats and seven one-bedroom ground floor flats were regenerated. One of the main challenges of the project was to tackle the condensation and mould within Wilmcote House that caused inhabitants health issues.

In keeping to the Passivhaus/EnerPHit standard, the architectural strategy involved wrapping the existing concrete structure (originally prefabricated using a Bison REEMA variant system), in a ROCKPANEL cladding facade system, ROCKWOOL external wall and flat roof insulation. 

The external insulation was fitted as a 300/400mm zone fixed to external steel frames to insulate and wrap the entire construction. Transforming the accommodation, the stone insulation protects the building from the weather, is fireproof, and reduces mould growth, whilst providing a comfortable internal environment for residents.

In addition to the cladding and insulation, the flats have been compartmented which prevents the spread of fire between flats within the building and upon its facade. The glazing was also replaced, a new heating system installed, structural remediation of the external structure, and the windows were replaced. The roof was converted, upgrading existing levels of roof insulation (for thermal comfort and acoustic benefits), and the placement of fire rated composite entrance doors to the building adds to the building’s resistance to fire.

By improving living spaces and the appearance of the accommodation, the refurbishment increased community engagement, bringing Wilmcote House’s occupants together and increasing the quality of life. 

To view more about Wilmcote House, click here, to view a video of the Fabric First event, click here