The brief was to design a four-bedroom house which could accommodate the entire family as it grew. The parents had to have their bedrooms near the children while they are young, but the client wanted the ability to move to the other end of the house once the children become independent. Given the relatively small inner city block, having the house focus on an external space was important.
One of the main challenges was obtaining council approval. “We had the strange situation that council wanted the house to grow in size so that it addressed the rear street as if it were the front. This made the amount of external space shrink and the bulk of the building grow,” says Salvatore Rigoli, principal at Studio [R].
These council problems meant the design had to be reworked. The amended minor scheme was an extension at the back of the existing house, but there was not enough of a saving to justify a house that did not meet the client’s brief. Eventually a compromise was brokered.
To create a sense of space, areas in the house were arranged around the courtyard. All the living areas, the rumpus room and play room had large glazed areas facing the courtyard. “So that when you opened up all these big sliding glass panels, it felt like the surfaces were connected,” Rigoli says.
To bring costs down in the project, some products were replaced with others. For example, the roofing and side walling of the extension were detailed in zinc but were replaced with Colorbond corrugated custom walls. “We simplified some of the windows in terms of their designs. We also changed from timber windows to aluminium windows. We took out a lot of the built-in joinery that could go in as a second stage, like fire place design,” Rigoli says, with the zinc change saving around $40,000. Builder Brett Williams, director at New Life Building, also laid secondhand dry pressed bricks as face rather than rendering.
Rigoli originally specified zinc as he was wanted a solid, metallic volume and it allowed design detail that was finer in the corners, reinforcing the first floor as a solid volume. It also meant capping trims or corner trims did not look corrugated with a trim over the corners. To find an alternative material, Rigoli worked with a metal roofing contractor who was used to looking at minimising trims. On a previous job, he had visited a Stramit factory to see the limitations of the material. For example, why a 25 mm fold was needed and a 10 mm fold was not possible.
A challenge was thrown in when it came to installing the footing. The footing was designed by a structural engineer to sit on the soil. As Williams was digging the footings, making the reinforcing and dropping them into the excavation, he hit rock in the corner. All the other footings had been excavated and reinforced and were ready to be poured.
This meant all the footings had to be replaced down to the rock. “That meant the building was sitting on a constant foundation, rather than half the building sitting on the rock and the other half sitting on the soil, which would’ve caused differential movement and cracking,” Rigoli says. “That was not a good thing to find early on in the project, but the builder did a good job in minimising the impact of that and obviously the costs associated with that extra work.”
The main challenge for Williams was the general building aspect of the project due to the tight site constraints and the varying ground levels changing over a metre in height. He says, “The building is based on square lines and open spans, and this made forethought always an important issue to give clean wall and ceiling finishes.”
Rigoli and Williams had previously worked together on Williams’ own house. Rigoli says, “We said [to Brett], this is the budget we want to achieve, let’s work out whether we can get there. Brett put in a lot of time and effort into seeing what we could make cheaper, if there was any construction methods that could save money or what was the real cost from going from timber windows to aluminium windows? He did that research for us and at the end of the day, he came up with a lump sum price that the client was happy to go with.
“We’ve got a good relationship and he was interested and excited by the design and getting to build some quality detail. It was a positive that we had a good relationship before we entered into that process.”
