Retrofitting hospitals is a major challenge. Drainage and water supply systems are often decades old and under pressure from heavy, constant use, yet the building must remain fully operational throughout any upgrade. With little room for downtime and even less space for plant access, deliveries and materials, estate managers are left juggling efficiency with the realities of complex pipework replacement.
But with the right planning, approach and materials, pipes stuck in a cycle of failure, blockage and repair can be upgraded with minimal disruption. Done well, retrofit work can extend the lifespan and performance of hospital estates well into the future.
In many hospitals, systems are under increasing pressure, not just from age, but from the kind of waste they’re handling. Hospital drainage doesn’t just deal with water. Sterilisation processes, chemicals, disinfectants and medical waste all pass through these systems at higher temperatures and concentrations than domestic equivalents.
But because full replacements are expensive and disruptive, most systems have been patched over the years. The result is a mix of old and new materials that don’t always work well together. Different sections expand, corrode and degrade at different rates, and the cycle of failure, blockage and repair continues.
WORKING AROUND PEOPLE
Hospitals aren’t just hard to access; they’re also in constant use and can’t be closed for days while services are replaced. That means upgrades often have to be done overnight, or in small, isolated areas of the building. This is where lightweight, prefabricated plastic systems offer a real benefit. Sections can be fabricated offsite from accurate 3D scans and then delivered in sequence to site. Installation is faster, quieter and safer, especially in confined spaces.
At Cardiff Heath Hospital, a particularly challenging retrofit involved a severely degraded cast iron system that was leaking chemical and medical waste near critical care units. Urgent repairs were needed to keep it fully operational and ensure the safety of patients and staff, while reflecting the fact that the building is nearly ‘end of life’ and is due to be replaced in five years. A smart, staged solution was implemented using HDPE drainage components. Deliveries were scheduled to match installation progress, and the system was replaced without disrupting day-to-day operations.
And it’s not just drainage. At Middlesex University Hospital, an upgrade to the water supply system used 3D scanning to map the existing pipework and prefabricate new sections. These were installed over several nights, with the system recharged and handed back every morning.
SAFE, SEALED, AND BUILT TO LAST
Safety is a central concern in any hospital. Drainage systems made from HDPE, when installed as a fully sealed system (with no expansion joints or ring seals), reduce the risk of leaks over time, which is particularly important in high-risk areas like theatres and wards.
For water supply systems, anti-microbial pipework such as Polypipe’s MecFlow Fusion can add another layer of protection. Tests indicate that built-in anti-microbial additives can significantly reduce bacterial growth, including Legionella, offering additional protection in settings where water hygiene is critical.
From an installation perspective, avoiding hot works is a major win, especially in older buildings where fire safety is a concern. MecFlow Fusion uses an electrofusion process which requires a specialist tool but eliminates the need for blowtorches or open flames. This reduces the risk of heat damage to surrounding structures and faster, cleaner installation overall.
While sustainability isn’t always the first priority in a retrofit job with a tight budget, modern plastic systems, such as HDPE, generally have lower embodied carbon than metal pipework, making them a lower-impact choice in many retrofit scenarios. They’re also more efficient to transport, store and install, all of which helps reduce the project’s overall impact.
Ultimately, the goal is to deliver better systems for patients and staff. Upgrading outdated facilities improves efficiency, reliability and long-term costs. Retrofitting plumbing systems will never be easy, but the right method can stop it from becoming disruptive. By carefully considering safety, sustainability and minimal impact, specifiers can give peace of mind during the upgrade, and instil confidence that the systems will continue to perform for the next 50 years. www.polypipe.com/commercial-building-services