From the outset all options were
considered:
1. High levels of insulation:
Concrete raft floats on 200mm of closed
cell insulation which wraps round the
edge of the raft and up to DPC level.
Triple glazed windows and doors
250mm of external insulation to walls
Insulation at both ceiling level and
following the roof profile to maximise
effectiveness.
2. No cold bridges
3. High thermal mass:
In situ concrete ground and first floor
provide massive heat store.
Dense concrete blockwork internal
partitions.
150mm thin joint blockwork to construct
the external walls. All surfaces plastered
direct to ensure transmission of heat is
effective.
4. Natural cooling by volume and mass
South facing ground floor rooms have
3m ceiling heights to ensure stratification
of air so that the hot air transfers heat
into the concrete first floor and resulted
in those rooms never rising above 22oC
in the summer of 2014.
The central stair void rises 8.6m from
the ground floor and acts as a chimney
to remove hot air in summer. The two
roof windows at the apex can be opened
remotely to allow the escape of warm air.
5. Natural lighting and low energy
LEDs
Natural light floods the house during
daylight hours. Roof windows bring
light and warmth into the centre of the
dwelling.
At night the LED downlights provide
very good levels of lighting with
minimum energy usage. Some low
energy lights are used as features.
6. Draught proof and air tight:
particular attention was given to
sealing round all penetrations,
including treating both the inside
and outside of windows and doors.
Although the air tightness tested to
0.98m3/(h.m2), performance in use
is better than this as the building
resists both pressure and suction in
strong wind conditions.
7. Ventilation: Mechanical heat
recovery ventilation unit
8. Heat pump: low temp output to
underfloor heating, 45 oC to hot
water cylinder.
9. Solar roof mounted Photo Voltaic
Panels
10. Site layout
House orientated to face Solar South
South facing patio at reduced level to
provide shelter and promote heat gain
10
to augment air temperature and delay
the onset of evening cooling. Sun path
studies during design stage to define
productive fruit and veg growing zone –
reducing food and transportation costs.
This ‘total design approach’ using the
skills and experience of the architectural
team provides the innovative
environment which allows us to be able
to provide a house at Lang Lane which
far exceeds the design brief and acts as
an example which others can emulate.
However, we do not keep this
information to ourselves. We have
published most of the information
needed for others to follow our example
on our website in the hope that well
considered eco-designed building might
become more of a norm and that others
can follow our lead in ultra-low energy
homes which will perform well into
the next century, while contributing
the carbon reductions needed to keep
the global temperature rise to below 2
degrees C.