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1 Project name Grove Cottage Project summary Extension & Refurbishment of Victorian Townhouse using Passivhaus methodology and CarbonLite guidance. Certified to the Passivhaus Institute's new EnerPHit (refurbishment) Standard. [NEW:Passivhaus Trust awards shortlisted project - presentation available on these pages].phpp certification is based on 20 C, rather than the 21 C the house was heated to during 2010/11. Forecasts are based on a 'typical year' rather than the 'actual' year being monitored. Measured data here is from 2005/06 (before) and 2009/10 (after). Measured room temperatures show an average of 21 degrees centigrade during the heating season. Please note the final air leakage as certified under EnerPHit was an N50 of 1.0 ACH. When adjusted for 2010 average monthly temps.& an internal temp. of 21 C, PHPP predicted a space heat demand of 36kWh/m2.a whereas 35kWh/m2.a was measured. Project Description Projected build start date 11 Jul 2008 Projected date of occupation 01 Mar 2009 Project stage Occupied Project location Hereford, Herefordshire, England Energy target EnerPHit Build type Refurbishment Page 1

2 Building sector Private Residential Property type Semi-Detached Existing external wall construction Solid Brick Existing external wall additional information Existing party wall construction Floor area 135 m² Floor area calculation method PHPP Building certification Passivhaus certified Project team Organisation Project lead Client Architect Mechanical & electrical consultant(s) Energy consultant(s) Structural engineer Quantity surveyor Other consultant Contractor Simmonds.Mills Architects Andrew Simmonds Andrew Simmonds, Lorna Pearcey Simmonds.Mills Architects Alan Clarke, Peter Warm David Olivier Bob Johnson None None Eco-DC Design strategies Planned occupancy Space heating strategy Water heating strategy Fuel strategy Renewable energy generation strategy 2 adults and 3 children. Passive Solar + Mechanical Ventilation & Heat Recovery (MVHR) + replacement gas boiler inc. retention of existing radiators Replacement gas boiler + super insulated, solar ready hot water cylinder + all hot and cold water pipes insulated. Installed measures include a south facing roof area constructed to allow future installation of 4.5 m2 of solar thermal panels to feed into HWC Natural gas (minimised use of). Biomass not considered as appropriate fuel due to resultant air pollution issues (particulates etc) in a city residential area, combined with high capital costs associated with biomass equipment relative to low heat demand required. No electricity generation technologies currently adopted. Page 2

3 Passive solar strategy Space cooling strategy Daylighting strategy Ventilation strategy Airtightness strategy Strategy for minimising thermal bridges Modelling strategy Insulation strategy Other relevant retrofit strategies Passive solar gain maximised as far as possible mainly through creation of new South facing windows in existing house and new extension. Existing house on N-S axis (main elevations East and West). Use of new & retention of existing thermal mass (blockwork / brickwork) within insulation envelope (i.e. use of external insulation). Windows summer shading as result of window set back. MVHR has automatic summer bypass allowing automatic cooling at night during hot spells. More substantial rate of night time ventilation for cooling purposes also possible via openable windows (good arrangement for passive stack ventilation designed in). Extensive daylighting to all rooms to displace electric lighting. Maximising daylighting through careful sizing and design of windows and internal colour scheme (favours light off white colours). Some windows with splayed reveals (opportunity arising with existing house) increase light distribution and levels. MVHR provides ventilation with openable windows if required, (good arrangement for passive stack ventilation designed in). Existing house: external face of existing brick walls parged (thin layer of cementitious material used). New extension: internal plaster to blockwork walls + use of air vapour barriers in ceilings and some limited wall areas where timber frame was required above brick/blockwork. Adoption of 'thermal bridge-free' construction detailing for new construction and also in refurbishment work where possible. PHPP. Limited use of THERM. *Application of external insulation to solid brick and new blockwork walls*insulation of existing suspended floor*insulation of existing solid floor*new floor raft foundation with structural eps insulation below*renewal of existing roof and placement of insulation above existing rafters. New roof uses fully filled I beams. Family remained in house during all refurbishment and new build works. Page 3

4 Other information (constraints or opportunities influencing project design or outcomes) House had limited architectural detail on street facade: Painted brickwork. (Decayed) stone subcills to windows: (Painted) stone lintels visible above windows. An original carved stone plaque was mounted on the house wall. The subcills and lintels details have been recreated in the new render. The street side entrance porch will be rebuilt in timber and roofed in original slates. The plaque will be recreated, updated and mounted as before. Energy use Fuel use by type (kwh/yr) Fuel previous forecast measured Electri c Gas Oil LPG Wood Primary energy requirement & CO2 emissions previous forecast measured Annual CO2 emissions (kg CO2/m².yr) Primary energy requirement (kwh/m².yr) Renewable energy (kwh/yr) Renewables technology forecast measured Energy consumed by generation Airtightness ( 50 Pascals ) Date of test Test result Pre-development airtightness - - Final airtightness 16 Jul Annual space heat demand ( kwh/m².yr ) Space heat demand Pre-development forecast measured Whole house energy calculation method PHPP Page 4

5 Other energy calculation method PHPP results (EnerPHit certification file) are based on 20 C internal temps and standrd 'typical year'. 13 W/m² (demand) Predicted heating load Other energy target(s) Building services Occupancy Space heating Hot water Ventilation Controls Cooking Lighting Appliances Renewables Strategy for minimising thermal bridges As per stage 2 Vaillant natural gas non-system boiler with Alpha Pro 2 external circulating pump etc HWC details, insulated pipe details Paul etc Heat Recovery Ventilation Unit, frost protection preheater. Set for continuous heating - wall mounted Vaillant digital control and room thermostat and weather compensation Existing gas hob, electric oven, electric toaster...coffee maker with insulated jug, microwave. 100 % compact fluorescent. *fridge: Baumatic BFE *washing existing appliances: AEG Oko-Lavamat *dishwasher: ISE DW51 *electric tumble drier (now junked), MVHR serviced clothes drying cupboard. Also home office equipment; 2 laptops, 2 printers, router, office lighting. Home office is not separately metered. None 'Thermal bridge-free' strategy. For details - see uploaded documents Building construction Storeys Volume Thermal fabric area Roof description Roof U-value Walls description Walls U-value Party walls description Party walls U-value Floor description 3 337m³ 446m² Refurbished: fully filled I beams over old roof 0.08W/m² K External insulation approach. Some very minor areas with internal insulation. 0.12W/m² K Party wall insulated by injecting foam into mm variable gap between house gable wall and wall of adjoining house. 0.39W/m² K new extension floor Page 5

6 Floor U-value Glazed doors description Glazed doors U-value Opaque doors description Opaque doors U-value Windows description Windows U-value Windows energy transmittance (G-value) Windows light transmittance Rooflights description Rooflights light transmittance Rooflights U-value 0.13W/m² K Internorm, Edition range. 3g with insulated frame. Not PH certified, rather 'passivhaus suitable' approach used here. 0.87W/m² K uninstalled N/A A range of sizes to fit existing openings and in new extension. U values range from 0.87 to 1.15 (average 0.98), with a glazed fraction per window/door ranging from 39% to 71%. Glazing area 18 m2 of total window and frame area of 29 m W/m² K uninstalled 0.5% Fakro triple Glazed 0.52% 1.49W/m² K uninstalled Page 6

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