The Full Transformation Of Derby Tank Houses
The Project.
Located in Allenton just off the ring road near Spider Island is one of Derby’s oldest council estates known as ‘Derby Tank Houses.’ The estate of over 200 homes was built in the 1920’s to address post war housing shortage. They were constructed using cast iron panels covered in cement-based enamel and were so nicknamed the ‘tank houses’
In 2022 Derby City Council was awarded funding from the Social Housing Decarbonisation Fund (SHDF) to transform some of its housing to be more energy efficient, reducing carbon emissions and so help reduce energy costs for tenants. These major upgrades were to include External Wall Insulation, alongside new windows and doors and ventilation.
Due to the number of houses involved, the project was split into three distinct phases: Phase 1 - 78 houses, Phase 2 - 76 houses, and Phase 3 - 71 houses.
The project used the Wetherby Epsiwall External Wall Insulation System, fitted with 90mm enhanced EPS insulation boards. After installation, the thermal performance of the properties significantly improved, with U-values reduced from 1.10 to 0.27. Winter interstitial condensation, previously recorded at over 210g/m² per month, was completely eliminated.
To address the challenge of 10mm cast iron wall sections, a specialist fixing method was developed. This involved pre-drilling pilot holes and using self-tapping fixings through the insulation boards to ensure a secure installation.
The system included an alkali-resistant scrim cloth embedded in Heck K&A scrim adhesive, followed by a second layer of adhesive to create a flat, smooth surface. The finish combined WBS Heck Silicone 1.5mm textured render with brick-effect detailing in key areas, adding both durability and visual appeal.
Challenges.
One of the main obstacles was the 10mm cast iron wall construction. Fixing the insulation system securely into this material involved pre-drilling pilot holes and using adapted self-tapping fixings aligned through the EPS boards. The process was labour-intensive, with over 4,000 drill bits used throughout the project.
Asbestos was another major concern due to the age and original materials of the buildings. Before any work began, trials were carried out on two properties to assess risk and ensure that replacing windows prior to the insulation installation could be done safely for residents and workers alike.
During the early stages, nesting swifts were also discovered. To protect the birds, Westville worked closely with the Swifts Society, integrating bird boxes into the render and extending roof trims so the swifts could return safely year after year.
Westville transforming the area
Spotlight On Our People...
John Harmieson
Service Team
John played a key role in maintaining a clean and organised site throughout the project, helping reduce disruption for residents. His attention to detail was especially clear at handover, where he delivered a professional clean to each property exterior, ensuring the final finish matched the high standard of workmanship across the board.
Results.
The success of this project very much revolved around the collaborated efforts of all parties. This unique scheme needed specialist expertise and an exceptional team with a natural desire to work together.
What they collectively achieved was special, so special in fact that it warranted interest from ITV News! However, the real winners here were the residents. They were over the moon with the visual transformation of their homes, warmer living spaces and reduced energy bills, all apparent in their glowing testimonials.
Each dwelling now has an EPC rating two levels higher than the previous, making each property substantially more energy efficient. Everyone was proud of what was collectively achieved. New techniques were learned, and experiences were enhanced, all in time for the next phase of this continued collaboration.
Following the work in Allenton, residents are set to save an estimated £74,250 annually on their energy bills.*
This SHDF project will also prevent over 202 tonnes of CO2 from entering the atmosphere each year, that’s the equivalent of preventing 42 houses from using the national grid for electricity every year.**
Resident delight is our delight
A few of the residents’ comments…
- “I think my house looks beautiful, the whole area has been updated. I noticed how much warmer my home was during last winter.” Fisher Street Resident
- “The improvements have made a lot of difference, our home is warmer in winter, cooler in summer, no longer draughty and the condensation in the kitchen has cleared. The heating doesn’t need to be on for as long in the winter, so we’ve seen a big change in our bills. Previously we paid £60 per week on prepayment meters, now it’s £50 per month!” Turner Street Resident
- “The service was brilliant and the results are amazing. I have no damp, mould or draughts anymore, my house is warmer in winter, cooler in summer and has improved sound proofing. I am saving approx. £300 of my energy bills so am delighted with that!” Rowland Street Resident
- “I’m amazed at the difference in how my house looks and have noticed it’s warmer.” Upper Moor Road Resident
- “Delighted. My electric bill has been reduced by £4 per day!” Mellor Street Resident
- “Very happy with everything. Not had his heating on since Feb, and house definitely warmer since installation” Rowland Street Resident
- "I’m really pleased with the outcome of the house, it looks really good. I was very happy with the installers always having a conversation with them.” Whitehurst Street Resident
Recent projects by Westville
We’ve had the opportunity to work on some inspiring projects with some fantastic residential clients, businesses and local authorities.
