The Mosman Bay House explores two contrasting spatial experiences, one is dynamic and fluid and one is passive and contemplative. One focuses on the distant views to the river and city and one is embedded with the garden. This Dr Jekyll and Mr Hyde quality responds to the programmatic requirements of active and communal spaces; living, dining, cooking and private spaces; sleeping, study and bathing.
In a reference to The Eames 'Powers of Ten' we explored multiple scales of relating to the site fluctuating between distant views and the dynamics of familyrelationships, contrasted with the tactile engagement with the garden and pool. The upper level appears as a stranded boat, a vessel drifted down the river and washed up on the foreshore, "from the river you could be in the city but not on or of it. You could be back from it out there on the water and see everything go by you, around you, leaving you untouched" (Tim Winton- Cloudstreet).
A third space connects interior and exterior, upper and lower levels, one long space and a returning point of reference for day-to-day experiences. This is a space that refuses to end and changes rapidly with external conditions. This space collects north light and distributes summer wind chilled by a sequence of cooling ponds.
External materials are tactile and designed to weather naturally, the lower level is finished in a white sand render, the foreshore of white river sand. The upper level is recycled and lapped Jarrah, a fluid vessel that meanders and wears the imprint of interior activities and furniture, a space that refuses to remain static.
The house is stretched along the east and west axis of the site, the lower level spaces all face north on to intimate and personal gardens, collecting winter sun and passive heat gain. The upper level shifts north to create a continuous veranda for the lower levels, providing privacy from neighbours and protection from summer sun. The underbelly of the upper level vessel is stained black reflecting the ground in to the interior spaces. The north shift in the upper level also allows winter sun penetration in to the south neighbours external activity areas.
The garden was specifically designed by Carrier Postmus to engage with the architectural concepts creating a lyrical and holistic experience. A series of ‘dancing’ white barked eucalypts filter north sun while in dialogue with the tilting columns and the meandering lapped Jarrah walls and screens leading one to the pool ‘Billabong’.
A fernery creates a cool and lush refuge space reflecting green light in to the study and bathing areas. A subtle native ‘carpet’ garden and olive grey colour palette responds to the white river sand walls reinforcing a sense of river foreshore. A hidden space with gas fireplace and moving recycled water allows one to ‘drift’ on the edge of the property.
An integrated glass art by Pamela Gaunt layers the lines of the architecture with the meandering line of the river, reflecting pattern and colour on to the white island bench.
Sustainable Design This house is on a challenging long and narrow site in and east west orientation. This greatly influenced the environmental design of the house, it is stretched in an east west direction maximising the relationship of interior spaces to collect north passive heat gain in winter. The upper level shifts further north to create a continuous veranda protecting ground level spaces from summer sun while allowing the southern neighbour to still enjoy winter sun. The veranda and profile of the upper level was shaped by solar modelling assessing winter sun penetration to lower levels and in consideration of the functional requirements of the upper level.
A south facing open-ended gallery space extends along the entire length of the house allowing the southwest winds to filter through the entire house. A series of individual cooling ponds are placed adjacent to each internal door and opening allowing individual control of cooling. A ground level awning window with flyscreen accompanies each cooling pond. The southwest winds are funnelled by the sculptured and curved profile of the rear wall, increasing the velocity of the winds. The wind flowing over the pond is naturally cooled.
The sculptured form also allows natural light in to this southern space heating the walls and waxed concrete floor.
The ground level spaces can be compartmentalised to allow easy heating and cooling and individual control. Fans are provided to the ground level spaces for additional cooling. There is no air conditioning to these spaces.
The upper level includes north facing highlight windows designed to allow winter sun passive heat gain. It is clad in lapped and oiled recycled jarrah and is left to weather naturally over time.
A rear space helps to future proof the house and allow for co-generational living.
During the planning approval process the Director of Development was concerned our sustainable design approach would result in a house that would ‘de-value’ the area. We were requested to present to the mayor and development approval panel, mid way through the presentation the mayor asked why we had been asked to present, he noted the design and sustainable design principles were aspirational and believed ‘if built as intended’ would result in a project of significant environmental and social value.
Other Considerations: 25,000 Litre Water storage tanks supplying the laundry and garden. Grey water recycling for the wc’s. 3KW PV cells Low embodied energy for material and finish selection Passive heat gain. Dark floor surfaces for extra heat gain in winter. Natural finishes to reduce ongoing maintenance Use of white low voc paint to increase light reflection Use of reflective surfaces to increase light Low voc paints and cabinet materials Plantation timbers and certified timbers including plywood. Native garden, drought tolerant species Elevated garden designed to spread over the timber and provide additional shade (and fragrance). LED light fittings Low water consumption fittings. Light coloured materials on the roof and masonry walls to reduce heat gain.
Sculptured and Performance Based Steel Whilst steel may not be the most obvious materialon this project it is specifically designed and incorporated to be high performing environmentally and structurally.
The south facing sculptured wall was modelled to allow north facing light and heat gain. It is also specifically shaped to increase the velocity of the south-west wind, this passes over cooling ponds and in to the house via low level windows. The darkColorbond colour reduces reflection to the neighbours.
The structural columns supporting the upper level tilt and crank based on the requirement to park cars and boats at ground level. They dialogue with the white barked eucalypt trees creating a lyrical dance, eventually the columns and trees will be physically entwined.
A meandering pergola is supported by steel pipe with a structural flat bar fascia, the pipe enables battens to be connected at all angles (a detail first developed on our Orang utan Exhibit that is further developed in this project). The fascia bends in a dialogue with the meandering river and to protect the lower level glazing from summer sun.
The roof detailing continues the meandering profile and incorporates Pittsburgh seams developed in close consultation with the builder and roofing contractor.
Steel is critical to the success of the environmental and lyrical qualities of this project, it not only looks challenging but is critical to the ongoing environmental performance.
Lyrical Lighting The Mosman Bay House exploits the potential of lighting to dialogue with the formal and atmospheric qualities of the design and to be lyrical and unexpected. The lighting is critical to the unfolding experience of the design, at times it is required to exaggerate the curving qualities of the interior (the upper level walls and ceiling), or emphasize a material texture (sand finished render), to cast unexpected shadows (through the timber battens), to allow the occupants to follow a path and wander…in to the garden finding unexpected spaces.
In this design lighting can be silent (recessed wall lights) or demand attention, the kitchen light reinforces the stretched linear form of the island bench, hovering as per the island bench above the floor. At times the lighting comes from distant travel experiences, Alvar Aalto’s 1937 Helsinki Savoy Restaurant A330S ceiling lamps.
Lighting is always experiential, it is never soley ‘task’ lighting, it is spatial (the downstairs gallery space) and defines pockets of space contained within larger spaces, pockets that can be individually tuned to the occupant’s desire (the upper level space).Pockets that create subtle zones of space to allow the familiar to be together but maintain personal privacy.