Renovate & Extend follows the progress of a home renovation using a breakthrough lightweight steel construction system that reduces the need for larger structural beams, has beneficial environmental effects and expedites the construction process
Architect Kevin Starling of Designology describes this unusual renovation that at the time of writing is a work in progress. What is unique about this particular renovation is the use of a breakthrough construction technique using lightweight steel. Kevin explains in detail the progress to date, “The existing dwelling was a ‘well-worn’ detached 1950s three-bedroom, single-storey, triple-fronted, cream brick veneer with a terracotta tiled roof.
“The client’s brief for the project was to reclaim part of the underutilised substantial front setback for a separate formal living zone. The main bedroom at the front of the house could then be converted into a media room. There was no existing vehicle accommodation, so a location for a future carport was to be considered at the side of the house. The rear of the house would be opened up to create a large open family and meals area adjacent to a proposed deck area for barbecues and entertaining.”
Kevin elaborates on the client’s brief for the renovation, “The owners also required a first-floor addition that would provide two large double bedrooms, each with their own walk-in wardrobes and ensuites. They also required a separate room on this level that provided a space to ‘retreat’ away from the main part of the house. If possible they were also keen to introduce a west-facing balcony that addressed the leafy front street where they could watch the sun set through the trees. They were also very clear about retaining, reutilising and recycling as much of the existing structure as possible and achieving a site-responsive design solution.
“The new works required substantial demolition including the removal of the brick veneer cladding and chimney from the front west-facing wall of the lounge room; the terracotta roof tiles and framing stripped back to ceiling level; internal stud frame walls removed in the family and meals area and windows replaced.
The completed home would consist of a ground-floor level with a media room and sunken lounge room at the front of the house, which are both accessed from the entry. A private courtyard has been included within the front setback that can be directly accessed from the media room. There is also a study/guest room and another bedroom.
“Lightweight construction systems were specified for the construction of the first-floor additions to reduce the need for larger structural beams and to expedite the construction process. Light-gauge high-tensile steel framing made from TRUECORE® steel was specified for the first floor of this project, largely due to its high strength to weight properties. The frames were prefabricated off site so that once the existing roof was removed the wall and roof frames could be quickly erected. Being substantially lighter than prefabricated timber frames it was also quicker and safer with reduced off-site impact on neighbouring properties.
“The frames were easily assembled on site using cordless drills and tek screws largely eliminating the need for framing guns. The prefabricated steel framing costs are also very cost competitive with timber, there’s no warping of members and therefore no time-consuming straightening of walls required prior to installing wall linings. Connecting the steel framing to the existing timber frame is a straightforward process and a combination of readily available fixing methods can be used. Also, the risk of termite attack is greatly reduced with a steel frame as termites can’t eat steel.
“The light blue-coloured TRUECORE® steel framing certainly created a substantial amount of interest when it was first erected. The owners commented that there was a continual stream of people stopping in cars for a few weekends for a good look, I guess curious about what and why this material was being used.
“As with every project Designology is involved with, passive solar design principles were integrated in the design process. The reconfiguration of the existing ground floor plan and first-floor additions were oriented to maximise solar access to the living areas and bedrooms, allowing these areas to be heated naturally rather than solely relying on alternative non-renewable heating methods.
“The vaulted ceiling provides additional natural light to the centre of the house, therefore the need for artificial lighting is reduced and less energy required. This also created an opportunity to then feature the stairwell on entering the house and was also the basis for integrating stack ventilation into the design, which provides a passive means of purging the house of warm stale air through employing thermosuction principles created when windows are opened in the stairwell on the first-floor level. This methodology can dramatically reduce the need for power-hungry energy-guzzling airconditioning in the warmer months, while also creating a healthier indoor environment for the occupants.
“Roof insulation consists of an R1.0 sandwich blanket under the roof sheeting and combined with R3.0 batts immediately above the ceiling lining provides a very effective barrier to keep the heat out in the summer months, whilst retaining the heat within the building during the winter months. Once completed, the house will feature wall cladding and a roof made from ZINCALUME® steel.
“The cladding of the second storey was done in COLORBOND® metallic steel in the colour Cortex® to create a totally different, custom look and an architectural feature. With corrugated steel being such an iconic Aussie material, it was a bold move to incorporate it into a modern contemporary design. In contrast, the ground floor is ‘anchored’ to the earth with a black granite footing and stone cladding. The ZINCALUME® steel roof will also deflect sunlight, lowering the requirement for air conditioning in all the rooms upstairs.”
The project was designed by:
DESIGNOLOGY in association with the clients
115 Athol Street, Moonee Ponds Vic 3039
Tel: 03 9370 7775
The project was built by:
Builder: Glenn Harwood (owner/builder)
Roof: ZINCALUME® steel in a Klip Lok profile. Cappings and flashings are powdercoated black similar to the window frames – for more information contact BlueScope Steel
House frame: TRUECORE® steel – for more information contact BlueScope Steel Website: www.bluescopesteel.com.au
* The new sections of the house use pre-fabricated house framing made from TRUECORE® steel, which is unusual as it is being attached to the existing timber framework.
* Framing made from TRUECORE® steel was chosen as it comes ready to install and is extremely lightweight.
* Having been subject to termite attacks before on the existing timber frame, using a steel frame also ensured that the new section of the house would be safe from termites.
* Once completed, the house will feature walling made from steel and a roof made from ZINCALUME® steel.
* The floorplans have been oriented to maximise solar access to living areas and bedrooms so they can be heated naturally by the sun, minimising the use of artificial heating.
* The vaulted ceiling and roof area of the stairs and lightwell provide additional natural light to the centre of the house, reducing lighting costs.
* High-level operable windows in the ceiling assist with natural ventilation.
* A concrete slab has been used in the ground floor extension with thermostatically controlled in-floor electric heating. The slab provides excellent thermal mass and receives good solar access during the winter months to warm the house.
* Where possible, existing framing material, bricks and flooring has been recycled for use in the new house.
Photography: Lucas Dawson.