PASSIVHAUS | MAX FORDHAM (w.m-2) evaluation has also shown domestic hot-water usage patterns exceeding the default figures in the Passivhaus energy model, so were using figures informed by real-world usage on future schemes. Croft Gardens, Kings College Cranmer Road was followed by another project for Kings College: Croft Gardens. This offers additional accommodation for graduates and fellows through an ensemble of four buildings on one site. Its kept the same CLT primary structure, and initial airtightness tests have been excellent. The ventilation approach is similar to Cranmer, with a cascade system for the buildings without en suites (fresh air is supplied to bedrooms, transferred through circulation spaces, and extracted from toilets, showers, kitchens and store rooms), and balanced ventilation at each room for the en suites, with dedicated units ventilating the kitchens. The three building typologies and ventilation strategies are being delivered using a number of the same ventilation units, so maintenance and holding spares is simpler for the college. Feedback from Cranmer Road showed some students had unlocked and overridden the temperature controls for their rooms*, so were providing an alternative interface, intended to provide some occupant control, but without profligate energy use. *Space-heating controls at Cranmer Road are childproof, but not, it turns out, Cambridge graduate-proof! Lucy Cavendish College Lucy Cavendish College had an exciting brief for its new student accommodation, including making Data from the day with the highest measured space heating load, showing an average 8W.m-2 when external temperatures were between the two weather conditions against which Passivhaus tests it highly accessible and sustainable. This was a good reminder that while low environmental impact is a key part of designing for a climate emergency, buildings need to be used, useful and enjoyed to be truly sustainable. Passivhaus wasnt explicitly asked for, but we proposed it as a way of contributing to their net zero carbon aspirations, combined with the Max Fordham sustainability matrix as a way of addressing wider sustainability that falls outside Passivhauss remit. Weve shared the Passivhaus designer role with architects RH Partnership, and worked with some previous collaborators, including Smith and Wallwork structural engineers. The scheme has common elements with some other Cambridge Passivhaus projects: CLT primary structure, brick weather skin, space heating and domestic hot water from heat pumps. The differences have also given us some interesting pieces of design with which to engage: a hung tile faade at first floor and above, and different ground conditions. For both, the design detailing have been developed to be buildable and minimise A view looking north across the Croft Gardens site, showing two apartment buildings framing a shared landscape, which is integrated with the surface-water drainage strategy 22 December 2021 www.cibsejournal.com Bad files.indb 22 26/11/2021 15:16