Leading building authority BRANZ recently stated that quality bracing was a design factor separating the homes that structurally performed in the Canterbury Earthquakes from those which didn't. They suggest lightweight roofing as one of their 'rules for good bracing design'.
In an article titled ‘Better Bracing Beckons’ in issue #170 of BUILD Magazine (February 2019), they explain how most of the modern and traditional homes that suffered damage met the New Zealand Building Code’s B1 Structure clause. However, the 2010 and 2011 events generated earthquake demand above the forces on which our Building Code and standards such as NZS:3604: Timber-framed buildings are based.
Lightweight roofing reduces ‘earthquake demand’
BRANZ say the key design factor that featured in the most structurally sound homes was quality, stiff bracing, and suggest lightweight roofing as one of their ‘rules for good bracing design’.
They also found that homes were better when they were simpler in design, and had smaller interconnected spaces versus big, open plan areas.
Strength-to-weight a feature of Gerard
With individual Gerard pressed steel panels typically weighing between 4kg (satin) and 6kg (textured) per m² of roof coverage, Gerard offers a great solution for anyone looking to minimise design loadings.
It’s a system that still offers market-leading strength and durability, with three factors driving this performance:
- An aluminium-zinc coated steel substrate: inherently light in weight, yet strong and durable.
- An overlapping, interlocking panel design: an installed Gerard roof forms a single, tough structural unit.
- Horizontal fixing: Gerard panels are fixed through the nose of the panel at right angles to lifting forces produced by earthquakes and wind, offering superior durability over vertically fixed materials.
To learn more, feel free to contact Gerard Roofs at Specification@gerardroofs.co.nz