Flexible drainage for modern hospitals
Healthcare buildings are among the most complex environments to design and operate. Clinical needs evolve, departments expand or shift, and layouts often need to adapt long after the original design has been completed.
For four decades, our people have developed trusted and eco-efficient sanitation solutions used around the world. We believe technology can make a positive difference – and that dedication and competence are key to making it happen.
Yet traditional gravity drainage systems can make these changes difficult, as sanitary facilities are often constrained by fixed vertical stack locations and prescriptive drainage design requirements. As healthcare projects increasingly focus on flexibility, resilience and future adaptability, more designers and planners are beginning to recognise the advantages of vacuum drainage systems.
Vacuum drainage offers a fundamentally different approach to sanitary pipework design - one that allows greater freedom in planning, supports late-stage design changes and reduces many of the constraints traditionally imposed by gravity systems.
The limitations of gravity drainage design
Traditional gravity drainage systems are governed by BS EN 12056, which requires vertical stacks to remain as continuous as possible to maintain reliable flow conditions and minimise the risk of blockages and pressure fluctuations.
Where offsets are introduced, access points for maintenance are required. In healthcare buildings, these access provisions can create additional hygiene challenges and place constraints on how sanitary spaces are designed and adapted over time.
- These design constraints also limit flexibility, as the design for sanitary rooms and appliances often need to align vertically from floor to floor - something that can make late-stage design changes or future refurbishments more difficult and disruptive, says Kris Wojcik, Business Development Manager at JETS.
Why verticality matters in gravity systems
Gravity drainage systems rely on continuous vertical flow to maintain stable air pressure within the pipework. If pressure fluctuations occur, water trap seals can fail, creating a potential route for the transfer of bacteria or contaminated aerosols between rooms or floors.
- This transfer mechanism became widely recognised following the 2003 SARS outbreak at the Amoy Gardens residential complex in Hong Kong, where the drainage system was identified as a contributing factor in the spread of infection, explains Wojcik.
Because of these flow and pressure requirements, gravity drainage systems place significant restrictions on building layout. Toilets and sanitary appliances often need to follow vertically aligned stack locations, limiting planning flexibility and creating coordination challenges for architects and engineers.
Greater freedom for hospital design teams
Vacuum drainage systems operate differently from traditional gravity systems. Wastewater is transported through differential air pressure within a sealed pipe network, removing many of the constraints associated with continuous vertical stacks and gravity falls.
Sanitary appliances no longer need to align vertically from floor to floor, and pipework can be routed horizontally above ceilings or through service zones. This gives architects and engineers greater flexibility when planning hospital layouts.
Departments, patient rooms and treatment spaces can be positioned according to operational and clinical needs rather than drainage stack locations. The flexibility also supports late-stage design changes and future refurbishments, which can often be completed with significantly less disruption to the building structure and surrounding services.
Supporting adaptable healthcare buildings
Hospital buildings are expected to serve communities for decades, often through changing healthcare models, technologies and patient demands. Designing for adaptability is therefore becoming increasingly important.
For architects and engineers, vacuum drainage increases design flexibility by reducing dependency on fixed vertical drainage infrastructure. This makes it easier to adapt layouts, reposition sanitary facilities and carry out future refurbishments with less disruption to surrounding services and building structures.
Because vacuum pipework does not require continuous gravity fall throughout the network, installation and future modifications can often be completed with less demolition work and reduced disruption to operational hospital environments.
As healthcare design continues to prioritise resilience, infection prevention and adaptability, drainage design is becoming an increasingly important part of creating flexible and future-ready healthcare buildings.
Rather than constraining future change, vacuum drainage allows hospitals to adapt more easily over time while supporting evolving operational and healthcare needs.