Wahroonga is a recently completed Passivhaus in Ledbury, Herefordshire. The timber frame insulated with a mixture of sheep’s wool and ‘Warmcell’ (Uwalls=0.09 W/m2K) sits on a 200mm reinforced concrete slab (for thermal mass) insulated below with 300mm EPS (Ufloor=0.12 W/m2K). Heating is provided by a conventional gas central heating system.
Natural lighting has been emphasized by providing daylight from at least two sides in each room. Certified Passivhaus windows (Alphawin Uw= 0.68 W/mK) and doors (Alu2Wood Uw= 0.77 W/m2K) have timber frames clad externally in aluminium. The MVHR unit (Paul Novus 300) is located outside the thermal envelope in a small single storey extension to the rear of the house; water saving and A+ rated appliances, micro-bore hot-water piping, low energy lighting throughout. Externally, lime render and untreated local Douglas fir cladding; reclaimed Welsh slate roof tiles with integrated 5m2 Velux solar thermal panels on the south east roof elevation and two small green roofs on the single storey porch and MVHR unit extension.
The south east/south west orientation is not optimal and though it hasn’t overheated since June it was quite warm in a cool summer so additional external shading may need to be considered. So far the property is warm, light, comfortable and beautiful!
Wahroonga has been Certified with the following values:
Space heating = 14kWh/m2.a
Heating load = 9W/m2
Airtightness = 0.24/h
Solar thermal panels = 5m2
TFA = 129m2
Client: Ruth Busbridge (Certified Passivhaus Designer)
Builder: Mike Whitfield (Mike Whitfield Construction)
Architect: Janet Cotterell (CT&T Architects, London & Passivhaus Homes)
Construction Details: Howard Meadowcroft and Mike Whitfield
Energy Consultants: Nick Grant and Alan Clarke
Julia Bennett, leader of the Gloucestershire, Herefordshire and Worcestershire Group, has organised for the members to revisit a completed Passivhaus to find out how the owner, Ruth Busbridge, is enjoying living in it on Tuesday 11th December 2012 at 6.00pm. For more information visit https://www.aecb.net/news/2012/11/gloucestershire-herefordshire-and-worcestershire-group-revisit-a-passivhaus-in-ledbury/