White Gum Valley
Efficiency in the Valley, White Gum Valley.
This unassuming little gem is quietly nestled amongst its peers in the sustainable estate in White
Gum valley. But unassuming as it may be it is a leader in its community with perfect design
orientation, shading, cross flow ventilation and solar power this home boasts net zero energy use,
excellent rain water harvesting and energy efficiency rarely experienced in Perth.
This beautiful home was the brainchild of its owners and from the initial site visit they were
fastidious, methodical and engaging in both the design and delivery of this wonderful slice of
perfection. The site being a split-level cottage block although now seemingly quite efficient was
challenging through the design stages. An extremely large two car garage, storeroom and Private
rear entry is a fantastic use of space to the rear split level area and presents many opportunities for
a blank canvas to work with on the upper floor of the home. The clever location of the timber stair
along the exposed limestone retaining wall is a beautiful feature in the garage and compliments the
timber lined garage walls to create a feel of natural products in the garage space.
High performance Kommerling C70 Gold thermally broken Double Glazed Windows with Viridian
Lightbridge glazing, the inclusion of R-4 Bulk insulation to the raised timber floor, R-3 bulk insulation
to all external walls, R-5.5 insulation with a Polymer rendered wall system to the North and Western
facades, R-6 Bulk insulation throughout the entire roof space and R-2.5 high performance acoustic
insulation to all internal walls are all features of this home which further increase the buildings
thermal and acoustic performance thus ensuring the occupants a healthy and comfortable living
environment with minimal ongoing heating and cooling costs. The inclusion of a fully ducted Heat
Recovery Ventilation system further improves not only the air quality but maintains ambient
temperatures throughout the home at extremely efficient costs.
This home also has been tested for airtightness in line with passive house principles and returned a
fantastic result of 2.1 Ac/H (air exchanges per hour). A fantastic result considering the complexity of
the build. The home only has two 2.5KW split AC systems in the entire home and has already been
through its first 12 months of occupancy with both only being used for a very short period of time
during the summer on prolonged hot periods. Both internal temperatures and air quality are being
monitored in this home with exceptionally positive results. Once again, a clear testament to the
performance of this beautiful home.
This home is also predominantly premanufactured timber framed construction ensuring extremely
low carbon footprint and low embodied energy. Premanufactured external and internal wall frames,
floor trusses and roof trusses all ensure not only less embodied energy and lower carbon footprint
but speed of construction rarely seen in Perth. The home being built in a little under 7 months from
start to completion. The use of premanufactured timber frame in this home also resulted in huge
waste reduction on site which reduced cost and waste to landfill.
The heart of the home is efficiently designated to open plan living dining complimented by a
generous galley style kitchen area. The kitchen boasts architecturally designed cabinets, Induction
cooktop with down draft extraction and Exquisite Dekton benchtops. A challenge on narrow cottage
lots is to provide adequate light and exposure but this home boasts large quantities of both. The
open plan living/Dining area is complimented by large high performance double glazed sliding doors
to both the North and South elevations. Raking ceilings then climb up to additional high light
windows on the Northern elevation grasping every possible benefit from the Northern aspect
including solar heat gain to the thermal mass concrete floor. This is again complimented by carefully
calculated eaves shading throughout the home which meanders its way around the various facades
in gentle compliance with desired solar heat gain and local design codes.
This expanse of glass then opens up to a large North facing courtyard area conjoining both the
internal and external spaces with seamless perfection. Compliance with the estate design guidelines
policed by the estate architects ensures the home is designed to efficiently take advantage of North
and Western exposures and also avail of Cross flow ventilation when required. The home has been
designed extremely well facilitating maximum use of solar heat gain and cross flow ventilation but
only when required and in a controlled manner.
The rear of the home is reserved for the master suite sanctuary. A huge master bedroom with a
quietly secluded walk-in robe and private balcony is simply breathtaking. The space is orientated
West to take advantage of both the world renown West Australian setting sun and the thermal
efficiencies it offers. This space truly is a quiet retreat and can only be described as perfect once you
venture into the connecting ensuite. This area is finished to perfection with large format rectified
edge tiling, two large strategically placed windows, his and hers vanity with above counter basins, a
walk in shower area and a breathtaking standalone spa bath its difficult not to be impressed by this
space. All plumbing fixtures to this home have been strategically chosen to ensure the highest
possible wells rating for water efficiency.
The front of the home has been methodically laid out with the sole purpose of an interchangeable
use of space. The space has been designed quite efficiently to facilitate the incorporation of not one
but two separate living areas should the need arise. With its own separate living area to the North
west corner including a huge bedroom, very generous living room, a large bathroom and extremely
cleverly located home office to the underside of the stairs this space is perfect for either a young
couple or visiting relatives. The living room then moves through to the stairs which takes you up to
yet another example of design efficiency. The upper floor is a fully self sufficient one bedroom
apartment style space, complete with bathroom, kitchenette and living room. This is a clear example
of efficient use of space while maintaining multiple interchangeable beautiful and functional living
areas at the same time.
Strolling around the outside of the home we can clearly see efficiency and sustainability everywhere.
The external feature claddings are 87% recycled material and designed with minimum waste in mind
for the intended areas. The nature strips are adorned with water wise plants and serviced by drip
irrigation from either a community bore service or the large rainwater harvesting system to the rear
of the building. This system is also plumbed into the dual plumbing system servicing the toilets and
laundry area but more importantly on this particular project the extremely efficient Stiebel Eltron
heat pump hot water heater system is also supplied by the rainwater harvesting system which
automatically switches to mains water should the harvesting system run low. The home has also
been fitted with the ability to recycle grey water in the future should the client wish to. All of these
magnificent features coupled with the highest efficiency wells rated water fixtures throughout the
home ensures extremely efficient water use and harvesting.
The final piece to this puzzle of perfection is a 4.95KW battery ready solar system. The home has
been occupied for 8 months now and has accumulated $244 in outgoing electricity costs. With A
supply charge of $224 for the same period we know the home only consumes 25% of the energy
generated through the PV system. Considering this is a full electric home this is a fantastic result.
All of this is possible through the amalgamation of many design and build features ensuring the best
possible performance for the building to create the most healthy, sustainable and ambient living
environment for the end user.
Applying Passive House Principles for Comfortable, Healthy Homes