This project is a modernist-inspired elevated platform home that creates the sensation of being up in the trees.
Location
The house is located on a secluded bush block not far from the Margaret River surf coast.
Design
The upper floor of the home has been designated as the service zone – including the kitchen, laundry, bathroom and wardrobe, as well as a study. To enable a continuous flow of space, walls of this service zone stop short of the ceiling. There is also an absence of internal doors to further amplify the sense of a singular space.
This floor can be accessed via a raw galvanised expanded mesh walkway that enables views through to the landscape below. Thin galvanised columns also support the insulated upper floor concrete slab and a single ground floor bedroom/storage room and bathroom with an outdoor shower, providing privacy for guests.
Cues have been taken from homes of the 40s, 50s and 60s that had a 3.6m structural grid; efficient in terms of both structure and materials. A 3.6m grid enables the steel structure and concrete slab to be extremely thin, while also allowing the use of full 2.4m x 1.2m pine plywood sheets on the ceiling without wastage.
Sustainability
To optimise energy efficiency, large areas of low-e glass are capped by horizontal shades that exclude the hot summer sun while allowing winter sun to penetrate onto the charcoal pigmented floor slab, warming up the house. The south-facing side of the home also has narrow, louvred ventilation slots that work in tandem with large sliding doors to the north to expel any build up of hot air during the summer. At the same time, the home’s elevated form helps to catch cooling breezes.
Externally, the house is clad in colorbond sheeting, hot dip galvanised steel, raw compressed cement sheeting and raw spotted gum decking. These materials were chosen because they are durable, low maintenance and bushfire resistant.
Key materials/suppliers
Flooring
• Trowel finish charcoal concrete slab with husqvana hyperfloor finish
• Spotted gum decking and inset entry floor to suit BAL 29 rating
• Hot Dip Galvanised expanded metal entrance ramp
Cladding/roofing
• Colorbond Spandek profiled steel cladding and roofing
• Light coloured roof to maximise heat reflectivity
Insulation
• Roof: R1.3 55mm Earthwool Spaceblanket reflective blanket
• Ceiling: R5.0 210mm thick Earthwool batts
• Walls: Foilboard Ultra 20 (R2.3) + R2.5 High Density Earthwool batts to external walls
Structure
• Hot dip Galvanised steel exposed frame
• Plantation pine stud frame infill
Windows
• AWS commercial clear anodised sliding door frames with low e glass
• Breezway louvre inserts
Lighting
• Brightgreen LED downlights
• LED strip lights to bathroom and kitchen
• Premium Lighting Onyx LED exterior lights
Passive Heating and Cooling
• Northern glazing to living zones and calculated eaves overhangs ensure deep
penetration of winter sun onto the concrete floor slab for natural radiant heating.
• Dark coloured slab to absorb more heat energy
• Designed cross flow ventilation paths provide natural and rapid cooling during summer
months.
• Cross flow ventilation is assisted by having smaller openings (louvre and awning windows)
on the windward side and larger openings (sliding doors) on the leeward side to create a
pressure differential
Active heating and Cooling
• Space heating by wood fire
• House wired for ceiling sweep fans should client wish to install (no air conditioning)
Paints and finishes
• Hoop pine plywood ceilings finished with Low VOC Osmo Poly X oil
• Plasterboard walls finishes with Dulux Enviro2
• Decking finished with Cutek CD50 oil and left to weather grey
• Hot dip galvanised steelwork left raw
Water
• Rainwater is collected and used for drinking, washing and cooking (no town water
services)
• Water for firefighting is pumped from an existing bore
• Hot water system is a Stiebel Eltron Heat Pump
