Avoiding corrosion damage

Andy Holland, technical and marketing manager at Rapierstar, highlights why poor fastener choice exposes aluminium windows and doors to corrosion risks.

Most of us will think of aluminium windows and doors as being the ultimate choice for superb visual appeal, long-term performance with no maintenance and resistance to the harshest of weather conditions.

But while aluminium does not ‘rust’ – that term refers only to iron and its alloys like steel – putting it in contact with other types of metal can lead to costly corrosion issues.

It is a problem that we often come across as it usually occurs because the wrong type of fasteners are used for attaching hardware, such as friction stays, to the aluminium window or door frames. And while the damage caused to the aluminium frame is mainly cosmetic, the corrosive reaction that takes place can cause the fastener to degrade rapidly to a point where it breaks and the hardware detaches.

The choice for any aluminium fabricator is clear: use only austenitic stainless steel fasteners throughout the window or door construction and you’ll avoid this corrosion risk. Choose the cheaper option to save a few pence – principally carbon steel fasteners – and you’re on a path to costly remedial work, poor customer satisfaction ratings, and reputational damage. Is really is not worth the risk.

Putting different types of metal contact with each other in the presence of moisture will create the same chemical reaction that gives us batteries – galvanic corrosion. In the case of aluminium windows and doors, combining very inactive aluminium with more reactive carbon steel fasteners will lead to a rapid reaction that could see the fastener corrode in a matter of months in particularly aggressive coastal environments.

Austenitic stainless steel is a less reactive metal, which means it will not rust quickly and instead provide a reliable solution throughout the lifespan of the installed product. The tiny additional unit cost for austenitic stainless steel fasteners in the manufacturing stage is greatly outweighed by the financial saving of not having to deal with costly customer call-backs.

Birmingham based Abcell is one of the UK’s fastest growing companies of its kind, and today has an enviable product portfolio spanning the Guardian Warm Roof system, Global conservatory roofs, and now both Warmcore and Aluk aluminium windows and doors. With sales growth forecast to be in the region of 20% this year, Abcell’s success is underpinned by its commitment to technical excellence and dependable customer service, and that requires a focus on every component they use.

Abcell uses a wide range of Rapierstar fasteners throughout the manufacturing lines, including only austenitic stainless steel fasteners for Warmcore and Aluk. And, according to Nev Gleed, Abcell’s director of operations, this is because you can’t take risks with fasteners.

“The quality of our products is what sets us apart, so the fasteners must be right for every customer and application,” he said. “Warmcore and Aluk systems are proving extremely popular with our customers; strong demand, which we have supported by recent investment in state-of-the-art machinery, to keep production ahead of curve.

“Using Rapierstar austenitic stainless steel fasteners is absolutely vital to ensure these finished products deliver on their promise long term.”

With austenitic stainless steel fasteners to suit all aluminium window and door systems and product types, Rapierstar can provide expert technical support to ensure fabricators can avoid the risk of galvanic corrosion. To arrange a technical consultation and a free comprehensive health check on which fasteners are currently being used and where improvements could be made, call 01260 223311 or visit www.rapierstar.com.