--- title: "10 Drainage and Plumbing Checks Before an HMO Inspection" description: "HMO licensing inspections include drainage and plumbing. These 10 checks let landlords identify and fix problems before the council inspector does it for them." author: "Drains Cleared Engineering Team" published_at: 2026-05-26 canonical: "https://drainscleared.co.uk/help-and-advice/hmo-drainage-checks-before-inspection" tags: ["HMO","landlord drainage","HMO inspection","plumbing compliance"] ---Houses in Multiple Occupation (HMOs) are subject to mandatory licensing across the UK, and the inspection process covers drainage and plumbing standards in specific detail. A failed inspection triggers improvement notices, delays licensing renewal, and in serious cases, civil penalties. Most drainage failures flagged at inspection are problems the landlord either did not know about or chose to defer — both outcomes that the right pre-inspection checks prevent. Here are the ten drainage and plumbing items most frequently flagged in HMO inspections, and how to address each one before the council visits. ## 1. Blocked or slow bathroom drains However, with multiple occupants sharing bathroom facilities, hair and soap accumulation in waste pipes is significantly faster than in a single-occupancy property. An inspector will run water in every basin, bath, and shower. Any that drain slowly or not at all will be noted. Clear every bathroom waste trap and run a test before inspection day. ## 2. Toilet flush performance Additionally, every toilet must flush effectively and refill within 30 seconds. Weak flushes, running cisterns, and toilets that require multiple flushes are all noted as deficiencies. Check each cistern: the fill valve, flap valve, and flush mechanism. Replace any that are not functioning correctly. ## 3. Hot water supply adequacy Specifically, HMO standards require adequate hot water provision for all occupants. An unvented cylinder sized for a single family will be inadequate for five occupants. The inspector will check water temperature (must reach 50°C at the outlet within one minute) and whether hot water is available simultaneously across the property. ## 4. Cold water hygiene and Legionella risk For example, HMO landlords have a legal duty to conduct a Legionella risk assessment. This includes checking cold water temperatures below 20°C at outlets after running, checking hot water storage above 60°C, ensuring no stagnant pipework (dead legs), and flushing infrequently used outlets. A written risk assessment with a date must be available. ## 5. Visible pipe condition As a result of high occupancy and frequent use, pipework in HMOs deteriorates faster than in owner-occupied properties. Check under all sinks for dripping traps, stained pipework, or soft push-fit fittings that have been incorrectly installed. Any visible drip or stain will be photographed by the inspector. ## 6. Shared kitchen waste pipe capacity Furthermore, shared kitchens typically discharge to a single kitchen waste pipe. Check that the waste pipe accepts full flow without backing up and that the trap seal is intact (preventing smells). Grease accumulation in kitchen waste pipes is common in HMOs — [high-pressure jetting](/drains/drain-jetting) every 12 months keeps them clear. ## 7. Drainage outside the property In particular, inspect all external gullies and the inspection chamber. A flooded chamber, overflowing gully, or standing water in the chamber when no water is being used indicates a downstream blockage. Inspectors who observe overflowing drains during their visit treat these as serious deficiencies. ## 8. Bathroom ventilation adequacy Consequently, all bathrooms and shower rooms require mechanical extraction ventilation (or openable windows where regulation allows). Inadequate ventilation leads to condensation mould, which inspectors treat as a Category 1 Hazard under the Housing Health and Safety Rating System (HHSRS). Check that extractor fans are installed, operational, and appropriately sized for the room. ## 9. Documentation for drainage work Similarly, inspectors increasingly ask for evidence of drainage maintenance — particularly for larger or older HMOs. A [CCTV drain survey](/drains/cctv-drain-survey) report, a recent [drain jetting](/drains/drain-jetting) record, or a maintenance contract provides evidence of responsible management. Properties without any records create an adverse impression regardless of their actual condition. ## 10. Drainage for recent conversions or extensions Moreover, planning permission for HMO conversion requires drainage provision to be adequate for the new number of occupants. If the property has been extended or converted and the drainage system was not assessed at the time, there may be capacity issues. A pre-inspection [drainage survey](/drains/cctv-drain-survey) identifies any such problems before they are discovered under the worst circumstances. --- ## Pre-inspection drainage service However, arranging a professional drainage inspection before your HMO licence renewal is a straightforward process. Our engineers provide a [CCTV survey](/drains/cctv-drain-survey), written report, and clearance service — the documentation package that satisfies inspector scrutiny. Call **0333 772 0123** or [book online](/book-online).