Cocoa Works, York

Brief

The Cocoa Works York project is a refurbishment of the former Rowntree’s and Nestlé factory building in York, originally built in the 1890s to manufacture chocolate and sweets.

The neglected building, once responsible for making over a billion KitKats per year, was due to be restored to its former glory, providing 279 luxury apartments. A mix of studio, one-, two- and three-bedroom flats, the refurbishment of the 4,500m2 building was designed to bring back an all-important community feel to the area. With six floors, the Cocoa Works proudly sits as the tallest building in York, other than the Minster towers.

One of the key features of the project is the top floor penthouse deck, which along with the rest of the building, would need to remain true to its historic design features, while delivering a contemporary living space. The iconic redevelopment also needed to have sustainability at its heart, so any materials used would have to fit with these objectives.

Challenges

It was critical to not just preserve the integrity of the building but to also protect the health and safety of the operatives. Given the age of the building and the dilapidated state that it was in before the commencement of the project, H&S was a key challenge.

This was compounded by the scale and height of the building. We are acutely aware that falling from a height is a leading cause of injury and fatality in construction so it was imperative that robust risk assessment and close H&S monitoring was carried out for the duration of the project. Our number one priority was that interaction with the aged material or structure did not pose a risk to our operatives and that they could deliver the project on time but, most importantly, in a safe manner.

Solution

Given the complexities of the project, it was essential that any materials chosen would provide a lightweight roof construction. IKO Armourplan P and IKO enertherm cut to falls were specifically chosen to provide a robust membrane, without adding too much stress to the existing structure. As Armourplan P is polyester-reinforced PVC membrane, it offers enhanced mechanical properties over standard PVC membranes. Importantly, IKO Armourplan P provides an aesthetically pleasing finish, to help uphold the historic design of the Cocoa Works, without compromising performance.

Meanwhile, IKO enertherm was selected for its superior thermal performance. Despite being thinner than other materials, such as EPS, XPS and mineral wool, IKO enertherm has a higher insulation value. This was crucial to make best use of the space on the roof – transforming it into a stunning penthouse apartment. At around 32 kg/m³, IKO enertherm is a lightweight insulation board with ergonomic benefits, for easier handling, too.

Certa Roofing & Cladding worked seamlessly with IKO to ensure that the roofing installation was delivered on-time and on-budget. Every element was thoughtfully considered, to help future-proof the quality of this iconic building. Using the mechanically fixed IKO Armourplan system with a cut to falls insulation scheme, for example, was crucial to provide the correct drainage and reduce the risk of further maintenance further down the line. Plus, as this roof construction did not require any hot works, there was no need for any flame to be employed during the roof construction.

The completed Cocoa Works York project was named winner of the Best Refurbishment Project 2023 Award at the 2024 Single Ply Roofing Association (SPRA) Awards.