House Name:
Schellback Residence
Owners: Brian Schellback
Address: 61A Annaville Road, Jensen QLD 4816
Construction type: New
Climate Zone: Townsville is located in the Dry Tropics – there are two seasons: hot and humid (November to April), the wet season, and a warm to hot dry season with low humidity for the other half of the year.
Design/Build Process: The owner a retired architect designed and built this home himself
Summary
Owner Brian, describes the concept of his home simply as a tin shed covering timber boxes. With a 2.5 acre block on which to build, retired architect Brian designed and built this comfortable home to a relatively modest budget specifically with the aim of creating a home that is contemporary, Australian, and specifically designed for comfort in our tropical climate – without any reliance on air-conditioning. Cross-ventilation, orientation and shading were the most important design considerations for Townsville’s tropical climate. Materials used include a steel flooring structure, timber and plywood flooring, masonite clad timber framed walls and a tin roof. The result is a breathtaking beautiful yet practical modern tropical Australian architecture that transitions in colour from yellow at one end to red at the other. A boldness which definitely suits the design.
Roof
Galvanised custom orb roof oversized to provide ample overhangs over the building below to provide protection from the sun and rain. The majority of the roof slopes to the north at 15 degrees, providing ample space for installation of solar panels and the solar hot water system.
Roof Space
In a radical departure from common design, the roofspace is completely open. The sloping roof, openness to breezes and purposeful lack of insulation under the custom-orb (to encourage a small amount of heat transfer through the metal) all work together to promote a venturi effect that causes constant air movement through the roof space – even on breezeless days, ensuring warmer air is always replaced by cooler air and the ‘roofspace’ never heats up keeping the rooms cooler below.
Insulation
Foiled bubble wrap type insulation (insulation value R2.4) stapled down on the top of the timber boxes together with plywood rather than plasterboard ceilings, work together to further prevent heat transfer from above into the home.
Flooring
The home is raised 700mm above the natural ground. The floor is supported by steel posts (recycled from demolition) and timber joists and bearers (recovered from Townsville Hospital site). Decking around the home is plantation pine finished with single pack polyurethane. Inside flooring for the majority of rooms are chipboard sheets finished with multiple coats of coloured single pack polyurethane – it looks amazing, and you’d never guess it was chipboard. Flooring in the bathrooms is open slatted timber for functionality.
Brian comments that the home could have alternatively been built as concrete slab on ground with the added benefit of the thermal mass which would help to keep the home warmer in winter and cooler in summer. But that said, he likes the practicality of being able to access electrical wiring and plumbing under the raised floor.
Orientation
In addition to the roof sloping to the north, the long axis of the home also runs east-west allowing the living rooms and two of the three bedrooms to have outlooks to the north which is ideal for easy shading, good natural daylighting inside the rooms and access to prevailing breezes.
Outdoor Living
The outdoor living area is a shade sail covered deck that extends the internal open plan living area out into the outdoors. With views on three sides, and overlooking a funky circular plunge pool (made out of a cut off oversized steel rainwater tank), plus excellent connectivity to the living and kitchen areas inside, this is a living space that is very well used.
Cross-ventilation
Brian stated that in designing homes for Townsville’s tropical climate, that cross ventilation is the most important consideration.
Brian achieved this by planning an open plan living space and having an elongated rather than square floorplan. Rooms have been offset on angles and external walls staggered to ensure that every room has at least two external openings to the outside with the windows oriented to capture prevailing breezes. (Prevailing breezes come from the north, north-east, east and south-east predominantly in Townsville.)
The extensive windows also give the feeling that even when you’re inside that you have a real sense of what’s going on outside, eg what the weather is like, what the sky is like, views of trees, the garden and visiting wildlife. Characteristically of modern tropical design this home blurs the distinction between inside and out.
A large standard sized louvre window has been used repeatedly throughout the home. All rooms have at least two of these louvre windows on different walls making a triangle with the doorway to ensure excellent airflow through every room. A combination of clear and frosted glass has been used for enhanced privacy in the bedrooms. All windows are fitted with flyscreens.
Fixed timber louvre doors either hinged or sliding are used for all bedroom doors and an opening has been left above the doorways for extra airflow.
The open plan living area has a powerful Cardiff air extraction fan and whilst only rarely used it can create a breeze through the entire house. A ceiling fan is provided to the main bedroom.
Walls
The walls are timber framed with 9mm masonite signboard external cladding and MDF craftwood internal lining. There is no insulation in the walls heat transfer is limited by extensive shading and the thickness of the external cladding.
Preferring a modern aesthetic, shadow grooves and attention to detail in construction eliminate the need for addition of skirting boards or cornices.
In the bathrooms, the use of tiles/grout has been avoided through the use of 3mm laminex aquapanel wall sheeting and continuous form shower capsules.
Shading
The oversized roof, provides extensive shading to the entire house including walls and windows. There is provision for some sun to shine on the deck and inside for additional warmth in winter.
Energy
Solar hot water system, with tank on roof.
Minimal electricial appliances.
Compact fluorescent lighting has been used throughout.
Skylights are fitted to bathrooms for natural daylighting.
Pot belly stove for winter heat.
Water
Water efficient shower and tap fittings are fitted throughout.
Greywater from washing machine and shower redirected to garden.
Stormwater from the roof is directed to a custom made rock lined predominantly ‘dry creek’ bed, planted with native plants that is a stunning feature on the property.
A low cost pool has been created by innovative conversion of a large rainwater tank.
Landscaping
Majority of trees existing on the site were retained.
Additional extensive planting of shrubs along boundaries and along both sides of the 250 metre long driveway – a spectacular entrance.
Brian has created a pseudo creek bed, that is ‘dry’ most of the time and planted with natives with plants to manage stormwater runoff from the extensive roof.
The creation of garden immediately around the house cools the air around and under the home, making the entire home cooler and more comfortable.
A mix of native and introduced plant species has been used including wattles, yukkas, cardboard plants, palms and eucalypts. All plants throughout the property were selected for their low water use and are mulched and intermittently drip irrigated. Natural attrition claims less drought tolerant species.
Vegetables are grown in under a large wire enclosure that keeps out the possums.
Brian enjoys a wide variety of birds, frogs, lizards and roos.
(August 2009) (
