Innovative homes engineered to accommodate a harsh climate Tuesday, 10 February 2015

Over the past couple of years, 28 homes have sprung up on Christmas Island. But they weren’t so much as built, as assembled.
The homes are part of a project to provide housing for staff working for the Department of Infrastructure and Regional Development amid the island’s challenging tropical environment.

The homes were constructed by GHD and project partner Canstruct as part of the $26.6 million Drumsite Village project that was a finalist in the WA Engineering Excellence Awards for 2014.

According to GHD’s project manager, Cameron Owen, part of the engineering challenge was determining the best style of house to suit the harsh conditions.

The island is located 2,600 kilometres north-west of Perth in a sub-cyclone region that is subject to monsoons for six months of the year.

Much of the land is either chalk, limestone or extremely hard rock, and houses also have to be designed to resist termites and mould.

“It's also a highly corrosive marine environment, and combined with phosphorus mines, there's plenty of corrosion and weathering,” says Owen.

Owen says GHD was responsible for overseeing site selection, environmental approvals, stakeholder consultation, procurement processes, design development, and managing construction of the homes.

The solution consisted of using Canstruct’s Force 10 ‘flat-pack’ housing system.

This involves homes that are pre-fabricated in pieces in Australia and transported to the island in shipping containers, and then assembled and erected.

The method involves an interlocking, galvanised steel floor, wall and roof system, with polyurethane insulation that provides good thermal qualities.

Canstruct says using the compressed fibre cement sheets, steel framing and insulation represents the latest thinking in design for tropical homes.

“They put it under pressure and fill it with expanding foam and it's got built-in conduits and they design each panel so window penetrations, service penetrations are all built in there, and then they package it up into containers and ship it off,” Owen says.

GHD says the Force 10 system is built to withstand cyclones and earthquakes, is fire resistant and impervious to water penetration.

With their distinctive angled roofs, all the buildings all have a covered deck to make the most of sea breezes and an 8-Star energy rating.

"Clients are really pleased and all the tenants are extremely happy, so it's worked out really well,” he says.

Image: Tropical homes ... the new houses on Christmas Island. Image supplied by GHD/Canstruct

By Tony Malkovic