Find out in minutes: Is your building’s drainage system a hidden risk?
When it rains, most of us don’t give a second thought to what happens to the water on the roof above us. But for large commercial buildings, poorly maintained drainage systems can lead to serious consequences – from flooding and structural damage to costly emergency repairs and compliance failures.
That’s why NSS, part of PTSG, has launched a free online Siphonic Health Check tool to help building owners, facilities managers and property professionals understand whether their drainage systems are up to scratch.
Unlike traditional gravity drainage, siphonic roof drainage systems use negative pressure to draw water rapidly off a roof through smaller pipework. They are commonly found on large commercial buildings such as shopping centres, warehouses, airports and sports stadiums. When working correctly, they are highly efficient. When they’re not, the results can be damaging and expensive.
The free online tool takes just a couple of minutes to complete. Users work through five straightforward prompts covering inspection history, drainage performance, overflow provision, survey methods, and access arrangements. The tool then generates a risk score based on the latest industry standard, BS 8490:2025 – giving a clear and immediate indication of whether the system needs professional attention.
This is particularly timely. BS 8490:2025 has recently been updated, raising the bar for how siphonic systems must be designed, maintained, and inspected. Many buildings across the UK may not yet be meeting these new requirements, leaving owners and managers unknowingly exposed.
Billy Gordon, Technical Manager at NSS, said: “A lot of building owners and facilities managers don’t realise their drainage systems may no longer meet current standards. The Health Check tool gives people a quick, straightforward way to understand their position and to take action before a problem develops.”
For those who receive a concerning result, NSS offers a full professional audit and repair service delivered entirely by its own directly employed engineers and specialist teams. The company also uses drone survey technology to detect potential problem areas before they develop into visible leaks and operates a 24/7 emergency response service for urgent situations.
NSS is a nationwide specialist services provider and part of the PTSG Group. From building maintenance and window and technical cleaning to platform hire and equipment testing, NSS delivers a consistent, self-delivered service across the UK, with safety at the centre of everything it does.
The free Siphonic Health Check tool is available now at nssgroup.com/siphonic-health-check. To speak to a specialist directly, call the NSS team on 03459 677477.
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