Designing an iconic hotel on the Australian east coast? Designing a luxurious resort in the Pacific Islands? How about an office block in windy Wellington? Or an apartment building in a wind-tunnel in metropolitan Auckland? What is the wind-loading requirement? 3kPa? 4kPa? Or more?
Whatever system specified must meet that requirement. Right?
In April 2017 Pacbld tested the XpressClad PX40 system (an adhesive-fixed rear-ventilated facade system with top-to-bottom ventilation) to AS/NZS 4284 with Swisspearl Facade Panels.
As with any 4284 test, the Ultimate Limit State (ULS) was set. And for that Pacbld went for an above average 4.5kPa. The system "met” and achieved that, but they didn’t test at the largest booth in the country (and the only one capable of reaching 10kPa) just to “meet” their ULS.
Instead, they decided to see whether the test booth could really reach 10kPa, and to see how far XpressClad PX40 could go. So they turned the engine on and took it to 4kPa, then to 5kPa — hurricane strength — then to 6kPa, and then to 7kPa. But it was happening too slowly, and that’s not how storms work. They have unpredictable surges. So the Pacbld team pushed it to 9.75kPa — and the system held. They even pushed for 10kPa but the technician said, “I can’t do it, I haven’t got the power."
But the system held — at 9.75kPa! No failures. No cracking. And that engine was giving it everything. The Swisspearl facade panels bowed under the pressure, but they did not crack or break. With adhesive fixed verticals at every 400mm, the Swisspearl panels were deflecting 30mm between joins.
The rails held. And the adhesive was allowing the Swisspearl to move. And for several minutes, the whole PX40 system was holding at 9.75kPa with no failure.
If the structure can handle the pressure, Pacbld XpressClad PX40 certainly can.