Spec Finish

Design 24 www.thefis.org Richard Mulvenna , Head of Design at fit-out specialist, Portview, describes a current project where although the client design team had supplied a RIBA Stage 4 pack of all elements with a detailed performance specification, the original plans had to be significantly revised to ensure that the firewalls could be built and installed to accommodate the builders’ work holes and comply with the system owner’s test evidence. NOTHING IS EVER STRAIGHTFORWARD T HIS was never going to be a straightforward project. With its reduced material palette and scale of exposed concrete and services within, there would not be anywhere to hide when coordinating and placing the interior elements. To add further complexity, we started in the wake of the Grenfell disaster and the Hackitt Report had not long been published, the industry supply chain was frantically reviewing its policies and guidance on how to install products and more importantly, what scenarios they were compatible for and what their fire test data covered. The client design team had supplied a RIBA Stage 4 pack of all elements with a detailed performance specification, so under its NEC4 contract, Portview quickly engaged with the other trade packages. All trade contractors had elements of CDP (Contractor Designed Portions) with multiple interfaces to co-ordinate and complete as we moved to RIBA Stage 5 for construction. Partitions and linings One of the largest packages with most interfaces across all other trades was the partitions and linings. With a high BREEAM target and value engineering targets prior to our appointment, it had been decided that almost all of the internal elements, including plant areas and risers, would be delivered in drywall construction. The client design team had engaged with British Gypsum (BG) during the Stage 4 development so as fit-out contractor, Portview felt it was more efficient to continue working with BG rather than working through the full design again with a different supplier. Technical details The MEP trade contractor had been appointed several months ahead of us so, once appointed, we asked for the builder’s works drawings to allow us to begin what we assumed would be a checking and confirmation exercise. However, this is where things began to become more challenging – given the level of services in such a large building, it quickly became evident that the proximity and quantity of required service apertures, coupled with the architectural openings, that there was little partition left in a large number of areas. This made us question whether the BG system alone would be structurally capable of delivering such an install while also maintaining the required fire and acoustic performance in accordance with BG tested solutions and the project specification. Richard Mulvenna, Head of Design at Portview