Box Twenty are working with Acorn Property Group on this exciting redevelopment project centered around the iconic landmark chimney.

We were appointed on a Performance level of design services, whereby we were involved in producing the planning application design information, assisting in producing performance specifications and design proposals for tender, reviewing tenders and contractors’ proposals and will also be involved during construction for monitoring site activities and ensuring compliance with the original design intent.

This project is a mix of 105no. low density new homes including stylish 2-bed apartments and 2, 3 & 4 bedroom houses plus 6,000 ft2 of commercial offices centred around an iconic landmark chimney on the derelict site of the former Brooks Dye-works in St. Werburghs, Bristol. 24no. of the proposed homes will be affordable, with a mix of intermediate rent and shared-ownership.

This major regeneration project will also provide fully landscaped public open spaces and new pedestrian routes linking to the surrounding areas and neighbouring parkland. The former Brooks Laundry dates back to the 19th century when the site was used for industrial units by Brooks Dyers and Cleaners. Box Twenty were involved initially through the pre-planning stages to develop the energy, M&E & external lighting strategies for the development in order to achieve a successful planning permission, which was granted in August 2018.

Challenges included Bristol City Council requirements to consider the scheme for future connection to the Bristol Heat Network as our site was designated as being within the proposed heat priority area. This involved undertaking detailed consultation with the planning officers to agree a suitable strategy as the planners had a preference for a central energy centre to be established on the site.

Unfortunately, the site is in a flood zone and so requires substantial flood mitigation measures incorporated below the ground to attenuate the run-off from the site to acceptable levels. The site is also above a protected aquifer that sits 6m below the site. These constraints prevented the use of borehole and shallow slinkies for on-site Ground Source Heat Pump (GSHP) installations and made the installation of a DH pipework distribution unviable.

We were also required to undertake detailed modelling of both the residential and commercial elements to asses their performance against overheating. The residential units were tested against TM59 and the commercial building was assessed against TM52 criteria. By making adjustments to the building fabric, services strategies and by agreeing occupancy patterns for both elements of the development, we were able to demonstrate that both the residential and commercial elements passed the overheating tests.