wimbish

What is Passivhaus ? an energy and comfort standard primary energy demand space heating and cooling demand heating load Elements of a passivhaus high levels of insulation air leakage to below 0.6 air changes per hour The avoidance of thermal bridging The use of MVHR to provide constant fresh filtered air The use of passive solar and occupancy gains Passivhaus in Practice The principle is that the house retains all of the heat from occupancy, activity, passive solar gain and the like, and requires very small amounts of additional heating as necessary. Fresh air is provided 24/7 by mechanical ventilation, (with heat recovery so as not to lose any heat) Windows and doors are highly insulated and all internal surfaces are warm to the touch, including the glass, (generally around 17º) Temperature is generally controlled by passive shading and window opening when necessary. Air tightness reduces uncontrolled heat loss. and nothing else John Lefever Regional Head of Development Welcome Housekeeping Agenda Rural Housing Provider Working in close partnership with Parish and District Council Same principles applied as most rural Hastoe schemes Differences for Passivhaus Raising awareness through consultation – manageable target audience Early nominations - Resident education Buy in from residents – continuous support 2.5 year monitoring project sponsored by Technology Strategy Board On site with a second project of fourteen homes in South Norfolk - 6% uplift, CSH4 Considering more schemes in future Lessons learned will improve the sustainability of all our new homes Taking it Forward Innovation and how to communicate it Detailed drawing package Complete design before construction Architect retained by client Toolbox talks and site training Emphasise and understand sensitivities On Site quality control procedures procurement – no substitutes reduced tolerances breaking the ‘complacency’ chain Air Tightness Site champion with regular testing/inspection Awareness and Understanding increase through education Design training and understanding sequencing and timescales Procurement products build contracts Construction quality and quality control training Challenges for Construction Passivhaus at Wimbish What is Passivhaus Passivhaus in Practice Passivhaus at Wimbish Construction Issues Challenges for the UK Construction Issues Challenges for the UK Jane Keiller Sustainability Manager Now for the science bit… Walls 0.090 W/m2/k Floor 0.07 W/m2/k Roof 0.0782 W/m2/k Windows 0.79 W/m2/k MVHR – 92% efficiency 0.46 Air changes per hour [n50] Heating strategy: Small individual gas boiler and solar thermal to provide heating coil in air inlet and rad/towel rail in bathroom, Large thermal store to avoid cycling and provide DHW Walls 0.24 W/m2/k Floor 0.16 W/m2/k Roof 0.1 W/m2/k Windows 1.4W/m2/k Projected annual gas cost: Houses 2478 kWh - £101 Flats 1390 kWh - £57 Addressing Climate Change Rise of the Green agenda UK target to reduce GHG emissions by 80% by 2050 In 2010, UK carbon emissions rose for first time since 2003 Code for Sustainable Homes Government’s 2016 new build ‘route to zero carbon’ legislation Escalating fuel prices and security of supply Tackling Rural Fuel Poverty In 2000, government set target to eradicate fuel poverty by 2016 Hills Report March 2012: new ‘reasonable cost’ definition plus measure of extent and depth of fuel poverty Rural, off-gas, oil/solid fuel, solid walls = 50% of fuel poverty gap Rural LIHC household have average fuel poverty gap of £622 vs £362 for urban households Rural and off-gas have greatest fuel gap of all 4-fold increase in fuel costs predicted by 2020 Fuel poverty links with ill-health. Sustainability and Innovation Carbon assessments 2010 Retrofit focus Green Homes Standard Switching to gas and insulation Retrofit exemplar learning: heat pumps, PV, solar thermal Incentives: FITS/RHPP/Green Deal Next Passivhaus development at Ditchingham Construction with straw bales Sustainable Homes Ltd SHIFT Silver accreditation Why Passivhaus Low carbon building standard – combined with CSH Low tech ‘passive’ measures with little intervention from residents High energy efficiency Low energy bills and high comfort for residents Drive down build costs, replicable across sector Chris Parsons MCIOB Architects Building Consultants Passivhaus Consultants CSH Assessors Energy Assessors Thermal Modelling Planning Consultants