Selfbuilder & Homemaker – July – August 2019

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internal walls are plastered rather than plaster-
boarded and following Passivhaus practice, all
the joints in the house are taped to prevent
draughts.
The Green Building Store, near Huddersfield
in West Yorkshire, supplied the triple-glazed
timber windows and doors and the MVHR heat
recovery ventilation system and was a great
source of information and inspiration for
Stephen and his project team.
“We chose the Green Building Store because
we had great confidence in their knowledge and
expertise with Passivhaus projects,” says
architect and Passivhaus designer Eric Parks, of
Buckrose Ecological Architects in Malton, North
Yorkshire. “The MVHR system is functioning
really well and is virtually silent in operation.”
As Stephen wanted to eradicate his use of
fossil fuels and Old Forge Cottage is off mains
gas in any case, a Mitsubishi air source heat
pump was chosen for the minimal heating and
hot water requirements. There is just one
radiator in the whole house – in the lounge.
Electricity is provided by a £6,000, 5 kW solar
PV array in the garden, laid out on low level
racking. The electricity from the panels can be
diverted in four ways: to the house, to battery
storage in the garage, to the heat store or to the
grid.
It’s very innovative; if an appliance in the
house needs power, that is supplied; if there is
no call on the electricity, it is diverted to the 13.5
kWh Tesla Powerwall 2 battery. When the battery
is fully charged, the power is diverted to the 300

litre water heat store, and when the water is

heated to the maximum temperature, it is

exported to the grid. This cascade system

means that the maximum value from the solar

power is extricated for every kWh generated.

“As a specialist in renewable energy and an

active consultant in the industry, I wanted to

create a high quality eco house,” says Stephen,

whose air of modest authority suggests that he

thoroughly enjoyed the process of planning the

systems for his home. “The incorporation of

renewable energy takes the house to another

level – I’m aiming for a ‘no bills’ house. The

operation of the smart system will be monitored

over the next twelve months to see how this

system is developing.”

Architect Eric says that achieving Passivhaus

within the limiting planning restrictions on the

external appearance represented an interesting

balancing act: “Larger windows were out of the

question, so the smaller areas of glazing and

increased length of window frames and mullions

“The planners at the

council basically

argued for an exact

replica of what was

there before”

40www.sbhonline.co.uk july/august 2019