ROCKWOOL NyRock® Rainscreen 032 delivers certified category 4 hurricane performance in real-world build-up testing

As extreme weather events are projected to become more frequent due to climate change*, the demand for resilient construction materials is also rising. In response, ROCKWOOL has subjected NyRock® Rainscreen 032 to a robust, independent testing programme designed to reflect how the product is commonly installed on buildings. The tests demonstrated that the insulation can withstand wind conditions equivalent to at least a Category 4 hurricane *.

Carried out in accordance with BRE Digest 346 Part 7, the programme simulated 50 years of varying wind pressures. 125mm NyRock Rainscreen 032 was installed in a range of typical façade build-ups, including, critically, one that incorporated a breather membrane.

“Specifiers, contractors and building owners need every confidence that the products they’re using can withstand the weather of the future and have been tested in applications that reflect how they’re commonly specified and installed,” says Lisa Stephens, Product Manager at ROCKWOOL UK.

“A breather membrane is important to the testing process, as the wind can infiltrate behind it and exert pressure on the insulation. Despite this, not all rainscreen insulation wind load tests include a breather membrane.

“By testing our rainscreen insulation in a build-up that more closely replicates a façade’s design, architects and specifiers can make informed decisions, knowing the findings are rooted in common build-up scenarios.”

The ROCKWOOL testing programme examined the product in two common façade build-ups: a steel frame masonry façade comprising 125mm NyRock Rainscreen 032 installed in ACS channel without additional mechanical fixings and a steel frame cladded façade with 125mm NyRock Rainscreen 032 installed with 50mm EJOT fixings. Both tests concluded that NyRock Rainscreen 032 can withstand a minimum of Category 4 hurricane conditions.

The 50mm fixing test was completed, recognising that space restrictions sometimes mean 70mm fixings cannot always be used. The testing confirmed that smaller 50mm fixings — instead of 70mm — are sufficient to endure Category 4 hurricane wind pressure. Similarly, in masonry façade build-ups, NyRock Rainscreen 032 demonstrated its strength without the need for additional mechanical fixings. In addition to providing independent verification for customers, the results highlight the potential for cost reductions and labour efficiencies.

“In practical terms, this means specifiers and contractors can save on fixing costs with the knowledge that a more complete build-up has been independently assessed for wind-load,” Lisa concluded.

NyRock Rainscreen 032 is part of the ROCKWOOL NyRock range of products that offer the lowest lambda stone wool insulation currently available in the UK and Ireland^** with 0.032 W/mK thermal conductivity. NyRock Rainscreen 032 also has a Euroclass A1 non-combustible reaction to fire rating and independently tested acoustic benefits.

For further details of the testing programme, visit rockwool.com/uk/wind-load-testing