London-based physiotherapist and downsizer Elizabeth Sharp spent four happy decades living in a five-storey, Grade II-listed Georgian house before deciding to self build on the site of her old home’s garage and rear garden.
“The house was beautiful but the heat was going straight through the windows,” she says. “I have poor circulation and I was really worried about being cold. If I was going to downsize I didn’t want something that would cost a lot of money to heat.”
Luckily, she chose to work with RDA Architects, who were keen to build a Passivhaus-certified home for her.
- Homeowner: Elizabeth Sharp
- Project: London Passivhaus
- Size: 110m²
- Build time: 16 months
- Build cost: £250,000
- Value: £1million
At the time, Elizabeth knew little about this ultra low-energy German building option, which is characterised by:
- massive amounts of insulation
- triple glazing (in this case, quadruple for the skylights)
- strict attention to airtightness
- a mechanical ventilation with heat recovery (MVHR) system.
She was soon sold on the idea though, once it became clear that she could achieve the standard for a modest build budget of £250,000. A swimming pool in the rear courtyard was an additional £80,000.
As far as costs went, it helped that the house is relatively simple in form and small — around half the size of an average self build in the UK.
According to project architect Richard Dudzicki, self builders can expect to spend around 3% more for a Passivhaus construction than for a more conventional build route.
Elizabeth now has the warm home she craved, with annual energy bills of around £300. The house is also cool during the summer months.
Internally, the architects have made the most of the modest space, with an open plan kitchen and living space across the ground floor, three bedrooms upstairs, masses of discreet storage space and two roof lanterns at the front and back of the house. The integral garage is large enough for an electric car with plug-in point.