Two men from two universities are combining their design efforts to coordinate a local alternative to the temporary housing we have seen since the 2022 floods.  

With a focus on sustainability, in the products they utilise being locally sourced, they have been working on a solution that is being called the Sustainable Bio Based Cardboard Housing System for Northern NSW.

Associate Professor Joe Gattas from the University of Queensland, and Professor Andrew Rose from Southern Cross University are the drivers behind the project, and they can’t speak highly enough of their third team member assisting, Mahmoud Abu-Saleem.

The professors wanted to make something specific for Northern NSW and looked around for what was readily available to build with and design.

“One of the main goals with the project here was to be able to use as much in the way of bio-based materials as possible,” says Andrew.  

“Not only bio-based but ideally materials that were otherwise low value or potentially even end up as waste products. A good example being the cardboard here. Some of this cardboard was literally recovered from dumpsters. It may have been recycled, but that's a fairly low-value use.”

The house sample that has been built is a test case. At 3m x 3.6m, it is half the size of a complete unit. The design is modular, so you can put more than one together to increase its capacity for a family. The size is limited by the ability to transport it - delivery is on the back of a truck.

The sample is on display at SCU for today only and then will be subject to more testing, including the longevity of the products the team have developed. The professors are hoping to get feedback from vested stakeholders to whom something like this can assist in the future.

The sample house in transit - all compact, ready for final construction. (Image supplied by Prof. Joe Gattas)

The house is built using two products that make up the bulk of the structure and provide it with a distinct look. The round timber posts support the front, and potentially back, and the walls, which are made from a timber fibre composite external skin, a standard interior vertical timber skin, with a cardboard support in between, giving the wall strength. 

“The structural core of the wall panels is a cardboard sandwich structure. There are layers of glue between the cardboard, and then it's shaped into this beam. So, if this was a conventional structure, that might be a timber stud.”

“This is actually at least as strong. And I think the testing that Joe and Mahmoud have done has shown that this is actually stronger than the standard foam core panelling, which is often used in these sort of panel structures.”

The team show the alternative products for use in the temporary housing.

Andrew elaborates on the localised importance of the materials they aim to use, “It's not just about using materials that are diverted from landfill but materials that can be sourced, locally, so that you're not trucking or flying in stuff. 

“Obviously, cardboard out of a dumpster is pretty local, and these timber components are sourced from Hurfords Sawmill, which is local. So this solution is tailored to the Northern Rivers.”

News got around about the project, and initially, it was the DPI (Department of Primary Industries) that approached Hurfords to invite them to be involved. 

Andrew Hurford said, “I think it's fascinating because the idea of doing something bio-based, which can be used in the end or break down naturally, rather than something that's made out of plastic that has to be deconstructed, or potentially becomes landfill, is a good idea. 

“It's low cost, and it can be part of the circular economy. I think it's terrific.”

A close up of the timber logs and the natural external finish of the structural wall. It can have finish applied to it, but the natural state is quite appealing.

The logs are made from thinnings, or trees in a plantation cut down to make enough space for the larger trees to grow. They aren’t large enough to cut flat timber from.

“We have a rounding machine that rounds the timber to make it into a constant size, which makes it easier to use in building. 

“It's a product that we developed to try to get better utilisation for those small logs from when we thin a plantation there. They're still quite strong and naturally durable. But you've got to get people to think about using round wood rather than square wood.” 

Discussing the details with an interested visitor.

All the materials selected support local industry and business, not only the two major components being structure and walls, but the base frame, the front and rear “windows”, as well as the roofing. 

Joe explains, “The flooring is a commercial product that's 50% waste timber already. The company that produces it already has a reverse logistics program.”

Their own methods reflect this ethos.

“In bonding the panel, we've tried to make sure that all products are more or less compatible with their own recycling strategies. We haven't worked through the full details of that but there are pathways for any of these panels as soon as they come off. 

“There's absolutely no steel in them. You can chip it, there's no environmental contaminant, and it just slots straight into current recycling processes.’

The house is being called temporary as it is undergoing testing, and is currently held down by strapping. There are no services applied to the structure at this point, which also adds to its temporary nature.

Depending on ongoing results, the house can be held down by more permanent means to provide longevity. At this point, they are confident that it will last 6 months and potentially up to two years. They can be taken down and stored for use at a later date.

The house itself takes about a week to prepare a module - but that would become quicker as more are made. The house ships, partially complete. It takes 3 to 5 people a few hours to half a day, and all you need is a drill and a ladder. A couple of neighbours can help each other out, and after delivery, both have a shelter within a weekend.

For more information on exactly where to find it, have a look at the earlier story this week.