Before Your HMO Licence: A Plumbing Checklist for Landlords

Why Plumbing Is Inspected in HMO Licensing

Peterborough City Council's HMO licensing inspection assesses properties against the Housing Health and Safety Rating System (HHSRS). Plumbing provision sits directly within several HHSRS hazard categories — personal hygiene, food safety, excess cold, and water supply — meaning deficiencies in bathroom provision, hot water, or heating can generate a Category 1 hazard rating, which blocks licence approval and can trigger an improvement notice.

The most effective approach is a pre-application plumbing audit — working through the checklist below before you submit and before the inspector visits. Our landlord services team carries out pre-application assessments across Peterborough.

The Pre-Licence Plumbing Checklist

Bathroom and Toilet Provision

• Count of bathrooms/shower rooms and separate WCs vs number of permitted occupants. Minimum ratios: 1 bathroom per 1–4 occupants, 2 per 5–9 occupants (check current Peterborough local conditions — they may exceed the national minimum)
• Every bathroom has a working shower or bath in good functional condition
• Every WC flushes correctly and has a properly seated pan seal
• All waste connections drain freely — no slow drainage or blockages
• Extractor fans fitted in bathrooms without openable windows (Building Regs requirement)

Hot Water Supply

• Hot water reaches every bathroom, shower, and kitchen sink in the property
• Hot water cylinder or combi boiler is sized for the number of occupants — not just a family-sized unit repurposed for 6+ tenants
• Hot water temperature at cylinder: minimum 60°C (Legionella control)
• Thermostatic mixing valves (TMVs) fitted to all bath and shower outlets delivering water at a safe 43–46°C at point of use — particularly important for HMOs with vulnerable occupants
• No dead legs (long sections of pipework that rarely have water flowing through them — Legionella risk)

Heating

• Every habitable room has adequate fixed heating capable of achieving 18°C at -1°C external temperature
• Heating controls accessible to all occupants — no single-point control that one tenant can use to deny heat to others
• No reliance on portable plug-in heaters as primary heating

Gas Safety

• Current Gas Safety Certificate (CP12) in date — issued within the past 12 months by a Gas Safe registered engineer
• Copies of the certificate available to provide to all tenants
• Annual boiler service up to date and documented
• No unsafe gas appliances or pipework — all visible pipework in good condition

Water Safety and Legionella

• Written Legionella risk assessment completed and on file
• Control measures documented and implemented (cylinder temperature, flushing protocol for little-used outlets, tank and pipe condition checks)
• Cold water storage tanks (if present) covered, clean, and free of debris

Cold Water Supply

• Adequate water pressure at all outlets — not just one floor or one area of the property
• Mains stopcock accessible and operational
• Individual isolation valves accessible for maintenance without disrupting all tenants

Common Failures That Block Licence Approval

Based on local inspection patterns, the issues that most frequently delay or block HMO licence approval on plumbing grounds include:

• Insufficient bathroom provision for the number of occupants
• No current Gas Safety Certificate — this is an automatic block
• Hot water system undersized for occupancy level
• No written Legionella risk assessment
• No TMVs on bath/shower outlets
• Extractor fans absent or non-functional in bathrooms

All of these are fixable — but fixing them takes time. A gas safety check can be arranged quickly; a new hot water system may take several weeks. Start the audit as early as possible before your intended application date.

Booking a Pre-Application Assessment

Our landlord services team carries out pre-HMO-licence plumbing assessments across Peterborough — visiting the property, working through the relevant compliance requirements, and providing a written report of any gaps alongside a remediation plan. This gives you time to complete any required work before the council inspector visits. Book an assessment online or call 02039514510.

For a full overview of what HMOs require, read our guide to HMO plumbing requirements. For gas safety certificate requirements, see our landlord gas safety guide.

Frequently Asked Questions

How far in advance should I carry out the plumbing audit?

Allow at least 6–8 weeks before your intended licence application date. A gas safety certificate can typically be arranged within a week. Hot water system upgrades or significant plumbing work may take 2–4 weeks to complete after a survey and quote. Booking an assessment 8 weeks out gives you adequate time to address any findings without rushing or delaying the application.

What if the inspector finds a problem I didn't know about?

If the council inspector identifies a plumbing issue during the licensing inspection, they will typically issue an Improvement Notice specifying the required work and a timeframe for completion. The licence application is held pending evidence of completion. It's far better to identify and resolve issues before the inspection than to receive an Improvement Notice — the council is less flexible on timelines once formal enforcement action has been initiated.

Do all HMOs need a licence in Peterborough?

Mandatory HMO licensing applies to properties occupied by 5 or more people from 2 or more separate households. Peterborough City Council also operates additional and selective licensing schemes covering smaller HMOs in certain areas. Check the council's current licensing register to confirm whether your specific property requires a licence under any scheme.

Can I use the same Gas Safety Certificate for multiple rooms/units within the HMO?

Yes — a single CP12 certificate covering all gas appliances in the property is issued per property, not per room or unit. However, every tenant in the HMO must receive a copy within 28 days of the check being completed. Keep a distribution record showing when each tenant received their copy.

Hot and Cold Water to All Occupied Rooms

HMO licensing requirements in Peterborough — administered by Peterborough City Council — require that all occupied rooms have reasonable access to hot and cold water. In a bedsit or studio HMO, this typically means a wash basin within or adjacent to the letting room. Shared bathrooms and kitchens must be sufficient in number for the occupancy level and must be maintained in good working order.

Minimum Bathroom and Kitchen Ratios

The national standards for HMOs specify that no more than four persons should share a bathroom and no more than five persons should share a kitchen. Peterborough City Council may apply local standards that are equal to or more stringent than the national minimums. Before applying for or renewing an HMO licence, confirm the current local standards with the council's private rented sector team.

Water Hygiene and Legionella

HMOs carry a higher risk of Legionella in water systems than single-occupancy dwellings due to more complex pipework, potential for infrequent use of some outlets, and higher turnover of occupants. A Legionella risk assessment by a competent person is strongly recommended before an HMO licence application. The assessment should identify any dead legs in the pipework, confirm hot water storage temperatures, and recommend a flushing regime for infrequently used outlets.

Hot Water Supply Requirements for HMOs

HMO licence conditions under the Housing Act 2004 and the Management of Houses in Multiple Occupation (England) Regulations 2006 require that hot water must be available at wash hand basins, baths, and showers at all times. In practice, this means the hot water system must be capable of supplying adequate quantities of hot water simultaneously to all bathrooms in the property, particularly during peak morning usage. For HMOs with more than three bathrooms, a single combi boiler may be insufficient to meet simultaneous demand — a system boiler with a correctly sized unvented hot water cylinder is often the appropriate specification for larger HMO properties. Discuss the heating and hot water system specification with a heating engineer before applying for an HMO licence to ensure the installation will meet the required standard.

Legionella Risk Assessment: Mandatory for HMOs

Legionella risk assessment is a more pressing obligation for HMO landlords than for single-let properties because the risk factors that promote Legionella growth — intermittent use of individual outlets, warm water at the margins of the legionella growth range (20–45°C), and scale and debris within pipework — are more common in multi-occupancy settings where bathroom usage patterns are unpredictable. The risk assessment must be documented and reviewed annually or when the property configuration changes (new bathrooms added, boiler replaced, tenants changing). In HMOs with hot water cylinders, water temperature at the cylinder must be maintained at 60°C or above, and delivery temperature at outlets should reach 50°C within one minute of running the tap.

HMO Plumbing Compliance in Peterborough

We carry out HMO plumbing inspections, Legionella risk assessments, and compliance upgrades for landlords across all PE postcodes. Call 01733 797074 for an assessment before your licence application or renewal.