Student accommodation can shift from intensive daily water use to prolonged low occupancy during the summer. That change is important because HSE specifically identifies vacant accommodation as a situation where stagnation needs to be managed. London halls of residence, private student blocks and shared student houses should therefore include summer closure and reoccupation within their normal water-safety planning.
Why summer vacancy changes the risk profile
During term time, high occupancy can provide frequent water turnover. During summer, entire rooms, flats or floors may remain unused. If the control scheme assumes regular use, those assumptions should be revisited before and during the low-occupancy period.
Areas that need particular attention
- Ensuite showers in vacant bedrooms.
- Shared bathrooms and communal kitchens.
- Accessible rooms that may be used less frequently.
- Cold-water storage tanks and boosted systems.
- Central hot-water plant and recirculating distribution.
- Little-used staff or maintenance facilities.
- Areas isolated during refurbishment or deep cleaning.
Flushing during low occupancy
HSE advises that outlets on hot and cold water systems should be used regularly to maintain water flow and minimise stagnation, and that properties left vacant may need a suitable flushing regime or other measures. The exact regime should follow the risk assessment and be carried out safely.
What should happen before students return?
Before full reoccupation, operators should confirm that the water system has remained under control, address any outlets or areas that have been out of use, verify relevant temperature controls and make sure planned maintenance has been completed. Where there has been prolonged shutdown, significant system work or evidence of control failure, competent review may be needed before relying on routine occupation to restore normal water turnover.
Does every residence need Legionella sampling?
No. Sampling is not automatically required for every accommodation block. Its use should be based on the risk assessment, system complexity, previous monitoring results and specific concerns. Sampling should support—not replace—the wider control programme.
Review after refurbishment or changes in use
Student blocks often undergo summer refurbishment. New ensuite facilities, reconfigured floors, pipework alterations and new hot-water plant can all change the water system. Where this occurs, the risk assessment and system records should be updated before the building returns to normal occupancy.
Our related article on Legionella after school holiday closures covers similar low-occupancy principles in education buildings.
Official guidance: Health and Safety Executive (HSE) L8 Approved Code of Practice, HSG274 Part 2, and Legionnaires’ disease: what you must do.
Student accommodation in London: Contact info@londonwatercompliance.com.uk for a site-specific assessment of halls, shared housing or private student developments.