The construction process of this remarkable clifftop home was unusual in more ways than one. Photo: Light & Lines.
When it comes to building homes on challenging land, where there is a will, there’s a way — a fact no more evident than on the finite strip of land between the escarpment and the ocean that is the Illawarra’s northern suburbs.
Here, architects and builders are constantly encountering new challenges, according to one local builder.
“Geotechnically it’s a high-risk area. Coastal erosion, slippage, landslides and subterranean water all create unique circumstances to contend with,” CKS Projects founder and managing director Keiron Moore said.
“That is becoming the reality for anyone building along the escarpment strip through Wombarra, Coledale and Scarborough, where the outlook is the drawcard and the ground underneath is the problem.”
His team just completed a home in Wombarra that has turned heads for this very reason.
The home itself is a looker — a split-level clifftop home with the ocean on one side and the escarpment on the other, all concrete, brick, wood and glass inside, oriented to drink in the expansive ocean views.
But the true interest lies less in the house than in what sits under it.
The block is classified as an escarpment zone, with subterranean water running underneath and the main road on the boundary.
As a knock-down rebuild, engineering and stormwater issues needed to be resolved before the design could sit where the owners wanted it.
With the proximity to the highway, the RMS got involved with the design and foundation system.
“It made it very difficult to build on the site unless we could guarantee that the structure itself was going to support their road,” Keiron said.
“It seems quite strange, I know, but it was a condition of consent to satisfy the RMS and stabilise the site.
“We had to go to some extremes. We dug sometimes 11 to 13 metres into the ground. We had to put a drainage system four metres below the slab of the house to pipe the water through. And because we weren’t allowed to pipe water off the cliff, we needed a level spreader to disperse water across the surface level, and strategically plant greenery to absorb it all.”
It had to go to a specialist engineer, who came up with an annulus pier system, which was unusual for a residential home.
“That kind of solution is more commonly seen on high-rise or commercial projects close to water. The specialist piling contractors we hired commented that they had never done this piering system in a residential project,” Keiron said.
This system accommodated a reality of the site — movement.
Instead of filling the massive auger holes solid with concrete, engineers installed hollow outer sleeves called pier liners to shield the main support piles. Driving friction piers down inside these oversized sleeves leaves an intentional buffer of empty space between the two layers. If the surrounding cliff shifts, swells or channels groundwater over time, the outer sleeve absorbs that pressure and movement while the inner piers — and the house anchoring to them — remain stable.
The home itself was designed by Mike Vail — an architect known for structures designed to be harmonious with their natural surroundings.
“I do not do sculptures. I like to do buildings which are part of the landscape and utilise aspects of the landscape. Utilise rocks that we bring up out of the ground, for example,” he said.
“Even the choice of recycled bricks. Bricks are fired clay; this house is built on clay. There are some very loose connections I’ve always been attracted to in architecture. I bring those back into a building to make sure it’s part of the landscape — not an object inside the landscape, which is saying ‘look at me’.”
Last month, the home claimed Contract Homes 1.9-2 million at the Master Builders NSW Southern Regions Excellence in Building Awards.
Original Article published by Dione David on Region Illawarra.
