Integrating Adaptation: Extra Care 4 Exeter
Designing for climate change adaptation: Opportunities for Architecture
architects • engineers integrated sustainable design mechanical engineering natural ventilation design passivhaus consultancy healthy building design landscape design permaculture design building monitoring research & development
Exeter Office Exeter Bank Chambers 67 High Street Exeter Devon EX4 3DT Tel. 01392 279220 Fax. 01392 279036
Bideford Office 18 Market Place Bideford Devon EX39 2DR (Registered Office) Tel. 01237 474952 Fax. 01237 425669
Our Team • Exeter City Council, Client, Project Manager, Structural and Civil Engineers • Gale & Snowden Architects, Mechanical Engineers, Landscape Architects
Passive natural vent
Permaculture design
• Exeter University • Jenkins Hansford Partnership - QS
Passivhaus certified
Landscape integration
Project Starting Point • New build 50 flats and communal facilities • Restrictive site • Shading of external courtyard space making it unusable • Institutional building with central corridor • Natural cross ventilation not possible
Shading diagram June 21st 18.00
Design for Future Climate Climate Change Adaptation Strategy Weather files used: 2030, 2050 & 2080 @ 50 percentile South West climate change is likely to have the following effects:
There is an overwhelming scientific consensus that the climate is changing
• average temperatures in the south west are expected to rise by 4-6 degrees over the next 80 years
• average solar radiation is expected to increase significantly, increasing the exposure to UV
• increase in exposure to pollen and higher ozone levels • wind loads and storm intensity are likely to increase • 50% reduced rainfall in summer with longer periods of drought and
• 50% increased rainfall in winter
We will need to adapt our buildings so that they can cope with higher temperatures, more extreme weather and changes in rainfall
Analysis
Methodology
• Literature research • Case studies • Thermal modelling past projects with future weather files • Risk Assessment • Ongoing IES thermal modelling at early design stages • PHPP (Passive House Planning Package) • Fluid dynamics analysis • Occupant heat stress analysis • Cost matrix • Integrated team studio working
2030, 2050 & 2080 @ 50 percentile with high CO2 emission scenario
Future Climate Change Risk Assessment Key Comfort Construction Water Management
• • • • •
User group vulnerability Increased internal temperatures Increased external temperatures Changing rainfall patterns Localised air pollution
Climate Change Adaptation Design • High levels of Dementia care • Cluster design • Usable soft-centre courtyard • Connection to others • Community and privacy
low energy - healthy - integrated landscape – non institutional
Passive Adaptation 4 Heat 1. Passive
Overheating Criteria not to exceed 1% occupied hours over 25 oC
• •
Cross flow vent 10-15% over heating improvement over single sided ventilation
Super-insulated, air tight envelope helps to stabilise internal temperatures and reduce solar gain penetration 3 – 6% improvement
• •
Intelligent window control 4% improvement Mass vs light weight 2-4% improvement with mass Less 1.5oc by microclimate
Local shading 2% improvement
• •
Evaporation / Transpiration
•
Pleasant shaded spaces for cooling Relocation of internal heat gains from plant outside thermal envelope 5% improvement
Green microclimate reduce summer temperatures by 3oC
Green roof
Cross ventilation Super insulated envelope Intelligent ventilation control Extracting heat at source Mass vs light weight Living plants / landscape Solar shading
Active Adaptation 4 Heat MVHR Activated during heat waves for minimum fresh air
Windows closed when external air temperatures are hotter than inside 2-4% reduction
Early warning temperature system to aid intelligent window ventilation control Drinking point to aid hydration
Ceiling mounted fans increase air movement and sweat evaporation
Heat extract at source
Supply air reduced by 10oC in summer combined with closing windows above 22-25oC reduces overheating to zero 2080
Close loop ground to brine heat exchanger
2. People centred
• Management / staff heat stress awareness and training • Drinking points • No cooking in flats during heat waves • Room ceiling fans
3. Active design • Heat extraction at source • Temperature sensor warning system for vent control • MVHR coupled with ventilation control • MVHR ground cooling
Adaptation 4 Air Pollution
Healthy design • • •
MVHR provides good air quality in bedrooms at night when windows are shut
• VOCs
Plants removes VOCs & CO2 MVHR removes VOCs & CO2
VOCs
Courtyard design provides fresh air microclimate
• • •
MVHR with pollen filter for affected users CO2
Smoke / smog particulates filtered by MVHR
• Pollen
Mosquito insect mesh on opening windows in summer MVHR at night for security on ground floors Building and Landscape design working together to provide healthy environments
Good ventilation rates Thermal comfort Filtration of pollutants and pollen using MVHR when needed Removal of CO2 by MVHR Non-VOC materials Plants used to help clean air Cleanable surfaces to reduce dust mites infestation Radial wiring to reduce EMFs
Adaptation 4 Rainfall Rain water harvesting tank on flat roof: Option A – ground and plants irrigation only Option B – as A plus flushing WCs, Sluices and laundry
Oversized gutters and downpipes
Water strategies • • •
For flushing WCs
Water retention via planting and landscape design Irrigation SUDs system Rainwater collection
SUDS / Attenuation system
For sluice rooms
Storage point at ground level Rain water harvesting under ground option B External area left for rain water harvesting tank
Water attenuation by roots Rainwater storage crate system = underground swale irrigation system Lower collection point for overflow
Wetter winters dryer summers – future rain files need adapting for designers
Aquaculture
Integrated Landscape Adaptation for Heat, Rainfall, and Air pollution,
Evaporation / Transpiration
Roof Garden Cooling effect Health and Welfare Biodiversity Rainwater collection For reuse in garden areas Deciduous climbers growing up balconies local shading Courtyard fresh air micro-climate Internal planting remove VOC’s and CO2,
Permeable paving to allow percolation into soils Sequence of rainwater storage crates for natural percolation to planting and pumped irrigation
Layered structure to planting, deciduous canopy for summer shading
Green roof 70-200cm substrate Sedum, herb, grasses Biodiversity. Reduce peak runoff. Reduce annual runoff by50-60% Cooler surfaces Improve air quality
• • • • •
• Pleasant shaded spaces for cooling Design to allow flooding into central planting shallow swale Green microclimate reduce summer temperatures by 3oC
Landscape Thermal comfort - cooling, shading Water - collection and reuse Biodiversity Health & well being Plants choice - species suited to challenging conditions, winds, drought, occasional flooding Minimise hard surfacing
Life Cycle Costing Cumulative Energy Related Costs
All costs have been discounted at 5% to represent present value. An annual increase in fuel costs of 4% has been allowed for and a reduction of heating demand of 30% from 2050 to 2080 has been included .
Cumulative energy costs for an Extra Care facility, built to 2010 Building Regulation requirements, for heating, cooling and additional future investments required to maintain adequate comfort conditions over the lifetime of the building.
Life Cycle Costing Cumulative Energy Related Costs
All costs have been discounted at 5% to represent present value. An annual increase in fuel costs of 4% has been allowed for and a reduction of heating demand of 30% from 2050 to 2080 has been included.
Cumulative energy costs for an Extra Care facility, built to Passivhaus Standard, for heating, cooling and additional future investments required to maintain adequate comfort conditions over the lifetime of the building.
Life Cycle Costing Cumulative Energy Related Costs
Comparison of Cumulative Energy costs: Payback of additional initial investment after approx. 13 years
All costs have been discounted at 5% to represent present value. An annual increase in fuel costs of 4% has been allowed for and a reduction of heating demand of 30% from 2050 to 2080 has been included.
South Elevation
North Elevation
Summary of findings • Early consideration • Employ sound building physics • Thermal modelling • Building layout designed for cross ventilation • Well insulated & airtight • Design for microclimates • Simplicity
Air conditioning can be avoided into 2080 with a passive approach The Climate Change Adaptation work has directly influenced the design of the building
Swim 4 Exeter A new indoor public municipal pool facility for Exeter, designed to meet Passivhaus standard including a main National/County standard swimming pool and a learners pool with supporting facilities, cafe, spa and fitness area.
Passivhaus swimming pool designed for Future Climate Change
Integrating Adaptation: Extra Care 4 Exeter
Designing for climate change adaptation: Opportunities for Architecture
architects • engineers integrated sustainable design mechanical engineering natural ventilation design passivhaus consultancy healthy building design landscape design permaculture design building monitoring research & development
Exeter Office Exeter Bank Chambers 67 High Street Exeter Devon EX4 3DT Tel. 01392 279220 Fax. 01392 279036
Bideford Office 18 Market Place Bideford Devon EX39 2DR (Registered Office) Tel. 01237 474952 Fax. 01237 425669