St. Loyes Extra Care
Passivhaus Extra Care for Exeter
Mission statement: "To design a new state-of-the-art, exemplar Extra Care Facility in Exeter"
The site for the St. Loyes Extra Care Home forms part of the 'Millbrook Care Village' development on the former St. Loyes College site on Topsham Road, Exeter.
The care home accommodation is to consist of 50 self-contained units with supporting communal facilities and staff accommodation, catering for the elderly and those with early onset/moderate levels of dementia as well as a high level dementia care facility. In delivering an exemplar care home, the scheme should: incorporate the latest thinking with regards to elderly and dementia care; incorporate low energy and healthy building design; employ high quality design and materials; achieve a homely, non-institutional and secure feel to the building.
The project has received additional funding for design work from the UK Government through the Technology Strategy Board's Climate Change Adaptation programme. The main climate risks that the project is aiming to address are: increased internal and external temperatures; unstable/changing surface temperature levels resulting in uncomfortable internal conditions; unstable internal temperatures and fluctuating humidity levels; increased wind and rain severity; reduced rainfall in summer and increased rainfall in winter affecting water supply and landscape; increased pollen count, airborne particulates and manmade pollutants due to gigher external temperatures and at time, less wind to help clear localised air quality; flooding.
Residents are likely to be frail and elderly and will require appropriate levels of thermal comfort. The building will need to be designed to maintain appropriate temperature and humidity levels throughout the year. With increased temperature rises due to climate change, the building will need to be designed to be future-proofed for internal thermal stability (minimising daily and seasonal temperature fluctuations).
Climate Change Adaptation
Adaptation for Heat - Passive
- Cross-ventilation - 10-15% improvement over heating compared with single-sided ventilation
- Super insulated envelope - helps to stabilise internal temperatures and reduce solar gain. 3-6% improvement
- Intelligent ventilation control - intelligent window control 4% improvement
- Extracting heat at source - relocation of internal heat gains from plant to outside thermal envelope 5% improvement
- Mass vs lightweight construction - 2-4% improvement with mass
- Living plants/landscape - green microclimates reduce summer temperature by 3% and internal temperatures by 1.5°C
- Solar shading - local shading 2% improvement
Adaptation for Heat - Active
- Ceiling-mounted fans in rooms - increase air movement and sweat evaporation
- Drinking points - aid hydration
- Management/staff heat stress awareness and training
- No cooking in flats during heat waves - central cafe
- Heat extraction at source.
- Temperature sensor warning system for ventilation control - windows closed when external temperatures are hotter than internal. 2-4% improvement
- MVHR coupled with ventilation control - supply air reduced by 10°C in summer combined with closing windows when temperature is above 22-25°C reduces overheating to zero for 2080 climate prediction
- MVHR ground cooling - close loop ground to brine exchanger
Adaptation for Air Pollution - Healthy Design
- Good ventilation rates
- Thermal comfort
- Filtration of pollutants and pollen using MVHR when needed
- Removal of carbon dioxide by MVHR.
- Non-VOC materials
- Plants used to clean air - courtyard design provides fresh air microclimate
- Cleanable surfaces to reduce dust mites infestation
- Radial wiring to reduce EMFs
- Building and landscape design working together to provide healthy environments
Adaptation for Water
- Water retention via planting and landscape design - attenuation by roots
- Irrigation SUDs system - underground swales and rainwater storage crate system
- Rainwater collection - ground and plants irrigation, flushing WCs, sluices and laundry