BELINDA: Welcome everybody and thank you for taking part in this forum on light gauge steel, or LGS. So, perhaps we can just kick off with an overview of light gauge steel, and what it is, and what the opportunities are in the Australian market. Maybe, Ken, you can give us some insight.
KEN: Light gauge steel framing is an important part of the steel market, and the housing market, and construction market within Australia. It’s got the advantage that it used automated processes of design and construction using CNC or computer numerically controlled equipment. It’s assembled in factories; then it’s delivered to site and quickly put up.
BELINDA: What’s uptake like at the moment in the Australian market? Are there untapped opportunities to use LGS?
PETER: Over the last five to six years the growth in the commercial space for lightweight steel frame has been incredible. Uptake in Victoria on residential projects is still quite low. There’s one really large manufacturer of housing, Steel Frame Solutions. They’re huge in that market, but the growth in Victoria has been in the commercial side of things. We (at Dynamic Steel Frame) have done the only four-storey lightweight steel frame building in the country out of lightweight steel frame, which up in about 13 weeks. We’ve done a three-storey project, which was 3,500 square metres over three levels, which we did, I think, in about 11 weeks. The uptake for the commercial sector is due to speed of construction. It’s incredibly fast to go from slab to roof because it’s lightweight, panelised, incredibly accurate, and premanufactured for the job.
BELINDA: Can we outline the different product types that are available in this material?
PETER: We manufacture wall frames, roof trusses, floor joists, and assembled flooring cassettes. We supply our frames into schools, transportable manufacturers, pod manufacturers who make bathroom pods as well. For high volume commercial residential buildings, lightweight steel is in pre-fabricated facades, pre-fabricated balconies, anywhere you could possibly imagine it to be, we can put it. If you can imagine the shape, we can manufacture that shape into the building.
BELINDA: Brian, what’s your view of the advantages of this material, say, versus timber?
BRIAN: It’s got a very good strength to weight ratio. When you’re talking about reducing the weight of the building, that has huge implications to the cost of the building, because typically with foundations of the building, it’s anywhere between 30% and 40% of the total construction cost. So if you can minimise or you can effectively make the foundations smaller, if you like, or not as much concrete, then you’re making the building more effective. It’s more costeffective and you have speed of construction as well.
“When you’re talking about reducing the weight of the building, that has huge implications to the cost of the building, because typically with foundations of the building, it’s anywhere between 30% and 40% of the total construction cost. So if you can minimise or you can effectively make the foundations smaller, if you like, or not as much concrete, then you’re making the building more effective. It’s more cost-effective and you have speed of construction as well.”
Brian Nasr, Structural Engineer, Structerre.
Whenever you’re talking about being able to pre-fabricate frames in an environment where it’s controlled, you’re going to be able to deliver quicker, construct quicker, and you have the advantage of being able to deliver project to the client quicker.
BELINDA: And what’s the limit in terms of how high you can go with these constructions?
BRIAN: You have projects in Europe and North America that have gone up between seven and 10 storeys. In Australia, I think we take a conservative approach to the way we design, but there is no reason why we can’t push the boundaries and deliver a project of that size in light gauge steel.
PETER: The Steel Frame Industry of America have done a study on how high you can go in lightweight steel. The numbers are about 40 storeys in lightweight steel, which no one’s ever going to build that way because it’s not practical. But strength-wise, 40 storeys is where they engineered it to. If they change the dynamics of the live loading of the building, they’d get 48 storeys and we’re talking structural steel.
BELINDA: Stuart, you’ve worked with Dynamic Steel Frame on a number of projects. Can you talk about how light gauge steel feeds into your design thinking?
STUART: The first few projects we did with Dynamic Steel Frame are really just one storey additions or finishing off the top floor of an apartment building. But the last one we completed with Peter was 41 apartments over three storeys. That came together as a whole design above a basement. It really gave us opportunity to test new ideas, new thinking, and new details.
BELINDA: This was the Zinnia Apartments scheme?
STUART: Yes, Zinnia Apartments in Yarraville. We found that one of the advantages of using a system like this is it’s actually flexible with the design. One thing with all pre-fabricated systems is that they need to be flexible to work with the design. One of the advantages of using LGS is that we can bring that into the process at a later time. There are a lot of variables and the construction methodology comes in later on, but we found, for example, on Zinnia that we could actually take what was designed to be a relatively conventional suburban apartment building and make it into a lightweight steel building, which was built more quickly and delivered on time for the tenants.
“One of the advantages of using LGS is that we can bring that into the process at a later time. There are a lot of variables and the construction methodology comes in later on, but we found, for example, on Zinnia that we could actually take what was designed to be a relatively conventional suburban apartment building and make it into a lightweight steel building, which was built more quickly and delivered on time for the tenants.” Stuart Marsland, Principal, Rothelowman.
BELINDA: What you’re saying is different to some of the thinking around offsite construction where there’s a lot of emphasis on design from inception; it’s actually an advantage of light gauge steel that it has the flexibility to work in with established program.
STUART: Absolutely. I know that in some of the offsite industry people like to think of a system first and foremost, but you really got to be flexible. You got to be dynamic. You got to work your way into accepted norms for building buildings. If you don’t do that, and if you’re just purely about the system, then unless you’re just building a single-storey building, you’re not going to get any bigger than that because when we’re building in urban areas where there’s lots of setback controls and other stakeholders who want to change the building, you have to be dynamic and flexible. It’s not just a case of putting boxes on a piece of land.
BELINDA: In terms of the process, say, with Zinnia Apartments or the other project you’ve mentioned Peter, how do you engage with all subcontractors and trades? Is it pretty much the same process as the traditional build or do you have to organise the program differently?
STUART: It was slightly different because we had to work hand in hand with the steel work shop drawing team. We produce the generic details, and they had to work out specific details, and we had to review them. It’s no different to doing a precast property building except the fact that we had to review different detail types. And in some ways, the details that came back from the shop drawing team were much more comprehensive than what you’d expect from maybe a standard precast shop drawing team.
BELINDA: Nick, what’s your take on working with LGS?
NICK: Yes, there’s definitely an opportunity there. We need to find a more cost-effective way to deliver the modules for schools and LGS could be opportunity to do that.
BELINDA: In terms of technology and the use of solutions such as BIM, Brian, what’s your experience in that regard?
BRIAN: So recently, we worked very closely with Dynamic Steel Frame. The introduction of these wearable technologies such as VR which are coming into the market at the moment, they’re really going to revolutionise the way we design. But even if we take it a step back and we have 3D modelling, which just makes it so much easier to visualise a structure and see what’s happening, that really does help the designers to understand the different load paths of the building.
PETER: We’ll often take a 3D model, from say, an architectural practice like Rothelowman, and we’ll get structural design from the engineers and then as a business, we’ll then model the structural steel and we’ll model lightweight steel, put it all together, and hand it back to the architect and engineer as a virtual model of what the building’s going to be like.
When we manufacture the lightweight steel, it comes directly from the model. Exactly, precisely what’s in the model is precisely what gets manufactured to accuracy of half a millilitre. There’s no ambiguity from that perspective. We’re manufacturing, not building
NICK: What’s your preferred time to get engaged?
PETER: As early as possible. And the reason we say that is an architect might get a brief to design a building in another material, and they’re going to design it that way, and then the builder says “Okay, we’re going to make this LGS,” there’s a redesign process to make sure walls and wall thicknesses and fire rating details and things are optimised for LGS.
KEN: Plus, you’ve built around the strengths of steel frame. You’ll never get an optimal design if you don’t engage early.
NICK: Who drives the process? Is it the client or the architect?
PETER: Look, bit of history; from our perspective, it’s always been the steel frame fabricator driving it or going to the builder and saying, “We can make this better in LGS.” and then it’s us driving that process. But we now have architects that we work with and call us up and say “What wall thickness do you want here, and here, and here, and here? What designs will suit your system?” because an experience I’ve had working with this, how do we make it work from the very, very get go?
BELINDA: Given the push towards midrise residential developments at the moment, is that a big opportunity for LGS?
PETER: The cost savings to go from, say, a three or four-storey concrete building to a three or four-storey lightweight building are huge. Time savings are big and cost savings are big. I think on the Zinnia project, the builders say they saved something around the range of half a million dollars on the job and a lot of that comes down to prior preparation.
BELINDA: Notwithstanding what you said about the resistance to LGS in the Victorian market, are you seeing industry engaging with the midrise sector with this approach?
BELINDA: Stuart, with your clients, do you see your role as educating them about the possibilities of light gauge steel?
STUART: Totally. We have clients coming at their buildings from all angles. Yes, if people are open to trying new things, we would suggest to them that they do look at light gauge steel because of the time savings and the cost savings that are involved.
The example we had on Zinnia Apartments was that the client on that particular project was a volume house builder who is building houses in the outer suburbs. He looked at the apartment market and he goes, “Surely we can do something slightly differently here.” He came at a 41 apartment, three storey building from a different angle. It’s good. We want to be part of that. We wanted to be part of the journey which looked at how to actually get that built.
I think we’re just seeing the market in Victoria start to become more accepting of trying new methodologies; then realising “This is actually much more precise, much cheaper and much quicker than just pouring concrete.”
BELINDA: I’d like to go around the panel get your thoughts on changes you’d like to see to encourage uptake of LGS. Stuart, maybe you can start.
STUART: I’d like to see more people paying attention to new technologies. The building industry is very much set in its ways, and it’s very, very parochial in terms of whether we’re building in Victoria or New South Wales. There’s another way of doing things. As a state, we’ve got a huge issue to deal with and that’s 100,000 people a year coming in to Victoria. I’d encourage people to go away and investigate some of these buildings that are being built, or have been built previously and ask questions about why they were successful.
PETER: We’re branching out into more of a volumetric style prefab as well; not just panels. We’re moving into flooring cassettes, but more importantly, bathroom pods, which obviously need the lightweight steel frame. And as lightweight gets far more accepted in the conventional space, we’re moving to the modular space.
KEN: We’d like to see steel being considered early on. To do that, we’ve got to increase the education of everybody in the design chain including the engineers that typically don’t get taught that aspect of design at university. So our focus is on building up that expertise within the industry so that it’s specified well and knowledgeably early on.
BRIAN: I think a lot of engineers when they look at relevant codes like AS4600, it’s very daunting. It’s not taught at university. But recent publications from NASH have made designing of cold-formed steel less daunting. I’d like to see engineers be able to design confidently with 4600.
NICK: I guess education for the industry is a big one as well as early engagement; using light gauge steel early enough to get all the benefits. Forums like this will help.
BELINDA: Thank you all for your presence here and for your expert insights.
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