Construction of a concrete haven

When a young couple from Melbourne decided to build their dream home for their young family on a sharply contoured site in Warrandyte, concrete was the material of choice in realising their dream.

Architects Impression - Front Elevation


The suburb of Warrandyte is known for its numerous parks and reserves dotted with large family homes where bush walking and experiencing nature is an everyday part of life. However, nature has also turned against it on many occasions, with the locality exposed to many of the major bushfires that has swept through Victoria over the years. 


The owners enlisted the services of Viola Architecture to design a large residential home showcasing the materiality of concrete as its main feature.

Approaching the home, one is greeted by a large precast wall with a profiled or ‘crinkle cut’ face, coupled with a semi-cantilevered canopy, which effectively marks the building entry and dominates and shields the rest of the home from the road above.

The rest of the structure, constructed from a combination of grey and black in situ off-form concrete, then falls away toward the back of the sloping site.

At the entrance, the visitor is greeted by grey and black concrete walls on either side of the hallway before encountering the folded and continuous cantilevered staircase.


Using considerable experience gained through the formwork contracting arm of Rosemont Constructions, the client set exacting standards on the concrete specification and construction practices on-site to achieve outstanding results. The large 690m² home features a polished concrete floor, honed to reveal bluestone aggregate sympathetic to the surrounding geology.

The structural slab was poured first, followed by the 100mm topping slab poured on the same day. Stringent quality control was employed onsite during this process, with the site manager ensuring there was no excess water, dirty shoes or smoking onsite when the slab was laid. This ensured that the client got a defect free slab, free of contaminants to be able to show the concrete off to its full potential when it was finally polished during a process of 10 passes of grinding.

Further to this, the slab also incorporated in-floor hydronic heating which was carefully laid amongst the reinforcement mesh utilising careful planning and a three tiered bar chair system, ensuring that all the mesh and heating coils remained exactly in place while the slab was being poured and finished.  

As a result, the client achieved a crack free floor with very little reliance on control joints to disrupt the flow of the large floor expanse. No less attention to detail was imparted on the imposing off-form in situ internal and external walls of the home.

The architect explored the use of alternate grey and black concrete walls though the structure to create a bold and dramatic statement both internally and externally. Once again, hours of planning and careful consideration was given to pour sequencing with alternating beam and column elements contrasting between the two colours of concrete as well as colours changing mid-span along large vertical surfaces. Between each colour change, the concrete pump required a complete washout (waste and excess concrete was used as pavers) and primed with the subsequent colour of concrete being poured, to ensure a clean, crisp contrast between the exposed wall surfaces.  

Internally the home is cleverly structured to provide zoned living for the family and guests on the entry level with the master bedroom taking up the entire top floor, overlooking the back of the property. Recreational areas extend deep into the belly of the home with a home theatre room making the most of the incredible mass of the walls to provide exceptional sound insulation. 

A basement cellar towards the front of the site maintains a beautifully consistent temperature thanks to the concrete walls and surrounded on all but one side with earth. This will also suit the purposes of an all-important retreat and shelter should the occupants ever need protection from the ravages of a bush fire.

A bold statement created using Black and Grey Concrete

Considerable interest has built around the home by the local residents during its construction, with some dubbing it the “Warrandyte bunker”.  This doesn’t bother the new owners one bit as they gaze proudly upon their bold creation. Knowing that they have realised their grand dreams to build a family home out of a material they are passionate about and have worked with most of their careers, they have also built a home that will provide a safe and resilient haven for their family and leave a lasting legacy for decades to come.

Project: In situ Family Home
Architect: Viola Architecture – Chis Viola
Builder: Rosemont Constructions
Construction commenced: April 2014

Concrete Systems:
Precast, In situ
Floors: Slab on ground, suspended slab