Light gauge steel helps improve seismic resilience

New Zealand and other seismic-sensitive nations are showing increasing interest in the use of light gauge steel framing in construction.

There has been a significant uptake in the use of steel framing over the last couple of years1, and one of the attractions is its performance in earthquakes, reports the National Association of Steel Framed Housing (NASH) in New Zealand.

While most global markets have seen an uptick in demand for steel construction based on efficiencies in build methodologies, seismic sensitive nations such as New Zealand and those in Southeast Asia are also finding comfort in its civil defence performance properties. This comes after experiencing first-hand the comparable losses and expense of rebuilding cities destroyed by natural disasters such as earthquakes and flooding.

Those who have historically used less structurally equipped materials in their build projects have endured higher rebuilding costs. It is of little surprise therefore that New Zealand building experts tasked with the rebuild of Kaikoura, Wellington and Christchurch, are looking for pathways that prevent unnecessary repair costs in the future. Answers are being found in light gauge steel framing.  Steel framing is a solution some not only advise to clients, they ensure it is at the heart of their homes too.

Those wishing to know more about the seismic qualities of steel framing can familiarise themselves with the results of tests carried out at Melbourne University. The tests were carried out in 2011, shortly after the Christchurch earthquakes. In synopsis, a test house was built (similar in construction to a real one) and subjected to high-level shaking tests in a lab environment. The steel framed house survived, displaying “an excellent performance under an extremely onerous earthquake testing programme”. For more, see here.

While earthquakes are unavoidable, it is reassuring to know that nowadays the damage caused to buildings may not always be so extreme. Thankfully, the capacity for buildings to be designed to withstand violent movement has developed.

NASH reports that seismic design is in increasing demand in both New Zealand and Australia, and steel framing is increasingly a key player in this area.

Steel framing is, or course, favoured for many reasons beyond its seismic advantages. What is also of massive appeal, NASH says, is the fact steel framing:

• Does not shrink, twist, warp, rust or rot removing the need for re-work
• Does not require chemical treatment
• Is lightweight, and so is easier to transport and move around onsite
• Does not require low moisture levels for building – so construction can continue in all kinds of weather
• Makes using external plaster cladding an option as steel framing removes any potential moisture issues caused by timber in the wall cavities, or cracking (ceilings, for example) due to movement in timber framing
• Is greener. Light gauge steel is 100 percent recyclable. There is no waste
• Performs better than timber in fires.

NASH says, when all the benefits of steel framing are considered, it is not surprising that residential builders looking for alternatives to timber framing are finding the answer in steel framing.

Many are left thinking it may have been a good idea to have made the switch years ago.

¹NASH general manager Carl Davies says market share for steel framing has increased from one per cent in 2008 to between seven and eight per cent today (2013). https://www.stuff.co.nz/dominion-post/business/residential-property/9435020/The-battle-between-steel-and-wood