Hurricane Force Tested…

Across the globe, heavy flooding, wildfires, and hurricanes are leaving towns, cities, and communities facing devastating consequences. With climate change increasing the severity of storms, even in the UK,¹ buildings must be designed to withstand stronger winds and harsher conditions than ever before.

That’s why we put NyRock® Rainscreen 032 through a rigorous testing programme – closely replicating a real-world facade application – to prove its ability to stand strong against even a Category 4 hurricane.

True-to-site tested

ROCKWOOL NyRock Rainscreen 032 has been independently tested to prove that, depending on the build-up, it can withstand a minimum of Category 4 hurricane conditions. 

Wind-load testing is common for most rainscreen insulation available in the UK and Ireland; however, testing programmes vary in terms of the build up tested and how closely they replicate what’s actually used on site.

For NyRock Rainscreen 032, we wind load tested the insulation in front of a breather membrane, mirroring common practice on UK construction projects and in facade design. The testing programme also assessed a steel frame cladded façade with a 50mm EJOT fixing, knowing that space restrictions sometimes mean a 70mm fixing isn’t possible.

By testing our rainscreen insulation according to how you specify and install it, architects and specifiers can make informed decisions and have more confidence, knowing our findings are rooted in real-life applications.

How it was tested

Testing was completed independently in accordance with BRE Digest 346 Part 7 Assessment of wind loads: wind speeds for serviceability and fatigue assessments, the industry standard procedure for assessing wind loads. During the procedure, products are exposed to a specific number of wind cycles to simulate a 50-year design life and to a specific category of wind pressure according to the Saffir-Simpson Hurricane Wind Scale. 

125mm NyRock Rainscreen 032 was exposed to pressure up to 2400 Kpa or 4000 Kpa, replicating conditions of a Category 4 or Category 5 hurricane, dependent on sample.

What was tested

A steel frame cladded façade comprising:

• Build-up: 125mm of NyRock Rainscreen 032 installed between steel brackets, mechanically fixed with 50mm EJOT fixings.
• Configuration: Installed over a Proctor Group self-adhesive Wraptite breather membrane.
• Performance: Exposed to 50 years of simulated wind pressure between 960 and 2400 Kpa, the equivalent of 139 mph winds (Category 4 hurricane)
• Further testing: The same build-up, tested with 70mm EJOT fixings, also withstood 2400 Kpa, the equivalent of 139 mph winds (Category 4 hurricane)

A steel frame masonry façade comprising:

• Build-up: 125mm of NyRock Rainscreen 032 installed within an ACS channel fixed to a light gauge steel frame, without additional mechanical fixings.
• Configuration: Installed over a Proctor Group self-adhesive Wraptite breather membrane.
• Performance: Exposed to 50 years of simulated wind pressure between 1600 and 4000 Kpa, equivalent to 180mph winds (Category 5 hurricane).

Proven performance 

The results prove that ROCKWOOL NyRock Rainscreen 032 retains its structural integrity even under hurricane-force winds and can withstand at least a Category 4 hurricane.

• Minimal degradation: The tested samples showed only slight embedding of washers, with no significant structural damage
• Added protection: The tests assess insulation before the final cladding is installed, meaning actual buildings benefit from even greater resilience

Smarter specification, faster installation, lower costs

Our research and testing is driven by the challenges architects and contractors face every day. 

Recognising that space constraints often limit fixing sizes, our wind-load testing programme assessed NyRock Rainscreen 032 installed with both 50mm and 70mm EJOT fixings.

The results were clear: NyRock Rainscreen 032 successfully withstood Category 4 hurricane conditions with a 50mm EJOT fixing in steel frame cladded facade applications, offering greater flexibility in specification without compromising performance. This means architects and contractors can confidently reduce fixing sizes where needed.

But the benefits don’t stop there. The same approach was applied to masonry wall configurations. NyRock Rainscreen 032 was installed within an ACS channel fixed to a light gauge steel frame without additional mechanical fixings. This setup successfully passed an extreme 4000 Kpa wind load test, equivalent to 180mph winds and Category 5 hurricane conditions.

For customers, this means: 

Potential cost savings:

• Fewer fixings mean lower material and installation costs
• Significantly reduced installation time: ROCKWOOL trials found that eliminating additional mechanical fixings can cut installation times by an average of 60%.²

References

1. Research by Newcastle University and the Met Office (Weather and Climate Extremes, 2023), https://www.ncl.ac.uk/press/articles/latest/2024/05/combinedwind-rainextremes/  
2. Time comparison conducted by ROCKWOOL UK sales team installed NyRock Rainscreen 032 with and without additional mechanical fixings over 3.24m²