Keyfix BBA Water Test on Non-combustible Cavity Tray System

Posted on 26 Jun 2023

Keyfix’s Non-Combustible Cavity Tray (NCCT) has been designed to capture moisture running down the internal surface of the external skin of masonry to channel it out  of the building. To prove its product’s excellence, Keyfix has tested its Non-combustible Cavity Tray system above minimum regulatory standards to see how much water it can withstand.

The Keyfix NCCT provides a complete non-combustible solution for the external cavity. It has a lifespan of 125+ years, holds an A1 Fire Rating, and is a self-supporting tray, independent of the inner leaf which therefore does not create a thermal bridge. The self-supporting nature of the range also eliminates issues associated with  differential movement, topped off with a keyed surface area to eliminate slip plane.

Keyfix’s Non-Combustible Cavity Tray system is certified by the British Board of Agrement (BBA), demonstrating that their products not only meet industry standards but that they have also undergone independent third party testing.

However, as champions of best practice, Keyfix wanted to test above minimum standards beyond being merely fit for purpose to ensure that its product was performing as highly as possible and protecting the building that it forms part of. The BBA durability test for water resistance on cavity walls entails the product being subjected to half a litre of water, per metre, per minute. Putting the NCCT to the ultimate test, Keyfix doubled the volume of water required as part of the BBA assessment.

Keyfix performed this test on an open wall to witness the water draining out of the building. This gave Keyfix the opportunity to ensure that all performance functions were working correctly, even under extreme conditions.

When conducting the tests, Keyfix found that despite doubling the volume of water the NCCT system was still able to withstand the conditions. In conjunction with the weep vents, buttering up the NCCT’s integral stop-ends restricts the flow of moisture towards ribs and encourages drainage via the weeps. During the test, water easily drained out of the primary weep vents without assistance from the supporting set of secondary weeps.

Even when manually blocking water from one of the weeps, the system ensured that the water flowed to the next available weep vent. As evidence of the product’s resilience, the ribs remained completely dry and leak-proof.

John Duffin, Managing Director of Keyfix stated “As champions of best practice we always want our products to be performing well above the minimum standards. Buildings should be made to last, therefore the products that form part of the buildings should be made to last too. By performing this test on the Keyfix NCCT we can see that the system easily drains heavy water flow out of the wall, without the use of tapes and mastics, ensuring that is protected against water leaks inside the building.”

To see the Keyfix Non-Combustible Cavity Tray in action, watch the video of the test here.