What should you do about mould in a rented property?

In England, mould in a rented home is a housing-condition issue, not a cosmetic nuisance or a tenant “lifestyle” argument. The practical answer is to report it, investigate the source, fix the cause, and keep dated evidence of what was done.

What should you do about mould in a rented property?

In England, you should report mould in writing, treat black mould issues in rental properties as a potential fitness and HHSRS hazard, investigate the damp source, remove the mould safely, and fix the defect or ventilation failure that lets it return. Private landlords owe a continuing duty that the dwelling “will remain fit for human habitation during the term of the lease,” and the updated HHSRS guidance lists “11. Damp and mould growth” under the 21 prescribed hazards, not the 29-hazard figure many older pages still repeat. Government guidance also rejects the standard defence that damp and mould are just tenant behaviour: “We are absolutely clear that it is totally unreasonable to blame damp and mould in the home on ‘lifestyle choices’.” For Scotland, including Glasgow, the route is different: private rented homes are judged under the Repairing Standard rather than the English s.9A/HHSRS framework.

What causes condensation in a rental property, and how do you stop it?

Condensation in a rental property is caused when ordinary moisture from people, cooking, washing and drying clothes meets cold surfaces or inadequate ventilation, and you stop it by keeping humidity in the 40–60% band, improving extraction, heating cold surfaces, and removing persistent moisture sources. Government HHSRS guidance says occupiers produce “up to a kilo of water vapour a day” through breathing, bathing, cleaning, cooking and laundry, and it gives the key mould threshold: “Moulds can grow where the indoor relative humidity persistently exceeds 70%.” Approved Document F gives the practical ventilation numbers landlords should check against: a kitchen needs 30 l/s with a cooker hood extracting outside, 60 l/s without one, a utility room 30 l/s, a bathroom 15 l/s, and a WC 6 l/s. The lazy answer is to tell tenants to open windows; the better answer is to prove whether the building can actually extract wet air fast enough.

Is there a tool you can use to check for damp or mould, and what does it cost?

Yes: a landlord can use a moisture meter for damp checks, but English law does not require a private landlord to own a damp meter, mould meter or hygrometer, and prices run from about £19.97 for a DIY meter to £559.80 for a surveyor-grade instrument. The confirmed retail examples are blunt: Screwfix listed a “Magnusson Moisture Meter” at “£19.97 Inc Vat,” while a Protimeter Surveymaster BLE was listed at “£559.80 inc VAT.” A basic damp survey is commonly quoted at £150–£250, with one price guide describing “a general visual inspection with tools like moisture metres” in that range. A cheap meter is useful for repeat readings, not a diagnosis: the real value is logging dates, rooms, photos, readings, weather, leaks and remedial works so that everyone can see whether the same wall is getting wetter again.

Is there a tool to measure air quality, and what does it cost?

Yes: humidity and indoor-air-quality monitors can measure the conditions that let mould grow, but the only air-measuring device English rented homes must have by law is a carbon monoxide alarm in a living-accommodation room containing a fixed combustion appliance other than a gas cooker. The legal CO duty is specific, and the penalty is capped at £5,000, not £7,000: the regulations say the penalty charge “must not exceed £5,000.” For damp and mould, government guidance is permissive rather than mandatory: “Smart sensors may be a useful aid to monitor temperature, humidity and indoor air quality.” The figures to watch are 70% relative humidity for persistent mould risk and 40–60% as the normal target band. Confirmed Aico HomeLINK pricing lists hardware/software at £281.91 for a gateway, £149.36 for a temperature/humidity sensor, and £195.30 for a version adding CO₂, so one humidity sensor plus gateway is about £431.

Why does water keep coming into a rental property even after fixing the guttering and roof?

Water can keep coming into a rental property after fixing the guttering and roof because damp often has more than one source, so repairing penetrating rainwater may still leave condensation, defective detailing, poor ventilation, cold bridging or another leak active. Section 11 expressly includes the duty “to keep in repair the structure and exterior of the dwelling-house (including drains, gutters and external pipes),” but government HHSRS guidance warns that “The cause(s) of damp can sometimes be difficult to determine and may have more than one source.” The numbers explain why a new roof is not proof that the problem is solved: the English Housing Survey found severe condensation at 3%, penetrating damp at 2%, and rising damp at 1%. The old “839,000 homes” damp figure still repeated by some trade pages is superseded; the 2024–25 survey says 1.4 million dwellings, or 5%, had damp.

What should you do if mould keeps coming back despite professional remediation?

If mould keeps coming back despite professional remediation, do not rely on Awaab’s Law timescales for a private tenancy: no Awaab’s Law deadline currently binds a private landlord, the quoted “12 weeks” is only a deadline to begin supplementary preventative work in social housing, and damp enforcement is not the £7,000 list but can run through a £40,000 improvement notice. The right next step is a fresh investigation focused on recurrence, because government guidance says: “If damp and mould have reappeared, further investigation and intervention should be pursued.” In social housing, the statutory idea is not merely cleaning; works must “make the home safe” and “ensure, so far as is possible, that the hazard in question does not recur.” The Housing Ombudsman’s benchmark is to schedule follow-up visits “for at least a year after works are completed.” Abodient is useful here as a property-document record: upload reports, photos, invoices and correspondence against the property so the chronology is searchable if the dispute escalates.

Last reviewed August 2026.

Sources

• “Private landlords owe a continuing duty that the home stays fit for habitation.”
• “URL:” Source
• “QUOTED LINE: "there is implied a covenant by the lessor that the dwelling—(a)is fit for human habitation at the time the lease is granted... and (b)will remain fit for human habitation during the term of the lease.”
• “SOURCE: Government (primary statute)”
• “Damp and mould growth is hazard 11 of the 21 prescribed hazards from 23 June 2026.”
• “URL:” Source
• “QUOTED LINE: "Physiological requirements 9. Excess cold 10. Radiation 11. Damp and mould growth”
• “SOURCE: Government guidance”
• “Government rejects the market's standard "tenant lifestyle" defence.”
• “URL:” Source
• “QUOTED LINE: "We are absolutely clear that it is totally unreasonable to blame damp and mould in the home on 'lifestyle choices'.”
• “SOURCE: Government”
• “Each occupier releases up to 1kg of water vapour daily.”
• “URL:” Source
• “QUOTED LINE: "Occupiers produce up to a kilo of water vapour a day, mainly through perspiration and breathing, bathing, cleaning, cooking and drying of laundry.”
• “SOURCE: Government”
• “The mould threshold is 70% relative humidity.”
• “URL:” Source
• “QUOTED LINE: "Moulds can grow where the indoor relative humidity persistently exceeds 70%.”
• “SOURCE: Government”
• “The target relative-humidity band is 40–60%.”
• “URL:” Source
• “QUOTED LINE: "Indoor relative humidity should be between 40% and 60% except for short periods where it will fluctuate due to factors such as bathing and cooking.”
• “SOURCE: Government”
• “Statutory extract rates are kitchen 30 or 60 l/s, utility room 30 l/s, bathroom 15 l/s and sanitary accommodation 6 l/s.”
• “URL:” Source
• “QUOTED LINE: "Kitchen (cooker hood extracting to the outside) 30 / Kitchen (no cooker hood or cooker hood does not extract to the outside) 60 / Utility room 30 / Bathroom 15 / Sanitary accommodation 6”
• “SOURCE: Government (Approved Document F)”
• “No law requires a private landlord to own a moisture meter, damp meter or hygrometer.”
• “URL:” Source
• “QUOTED LINE: ""competent investigator" means a person that, in the reasonable opinion of the lessor, has the skills and experience necessary to determine whether a social home is affected by a significant hazard or emergency hazard”
• “SOURCE: Government; established by searches reporting no mandatory meter requirement”
• “A DIY damp meter costs £19.97.”
• “URL:” Source
• “QUOTED LINE: "Magnusson Moisture Meter (594YC) £19.97 Inc Vat”
• “SOURCE: Secondary retailer”
• “A surveyor-grade damp meter costs £559.80.”
• “URL:” Source
• “QUOTED LINE: "Price: £559.80 inc VAT (£466.50 ex VAT)”
• “SOURCE: Secondary retailer”
• “A basic damp survey is £150–£250.”
• “URL:” Source
• “QUOTED LINE: "A Basic Damp Survey involves a general visual inspection with tools like moisture metres, which typically costs between £150 and £250.”
• “SOURCE: Secondary”
• “A CO alarm is required where a fixed combustion appliance is present.”
• “URL:” Source
• “QUOTED LINE: "a carbon monoxide alarm is equipped in any room of the premises which is used wholly or partly as living accommodation and contains a fixed combustion appliance other than a gas cooker”
• “SOURCE: Government”
• “The maximum penalty for breaching the CO alarm duty is £5,000.”
• “URL:” Source
• “QUOTED LINE: "The amount of the penalty charge must not exceed £5,000.”
• “SOURCE: Government”
• “No law requires a private landlord to install a humidity or air-quality monitor.”
• “URL:” Source
• “QUOTED LINE: "Smart sensors may be a useful aid to monitor temperature, humidity and indoor air quality”
• “SOURCE: Government; permissive not mandatory”
• “Market price for Aico HomeLINK equipment is £281.91 gateway, £149.36 temperature/humidity sensor and £195.30 sensor adding CO₂.”
• “URL:” Source
• “QUOTED LINE: "Hardware with software included £281.91 £149.36 £195.30”
• “SOURCE: Secondary manufacturer price list”
• “Guttering repair is the landlord’s structural/exterior obligation.”
• “URL:” Source
• “QUOTED LINE: "to keep in repair the structure and exterior of the dwelling-house (including drains, gutters and external pipes)”
• “SOURCE: Government”
• “Damp may have more than one source.”
• “URL:” Source
• “QUOTED LINE: "The cause(s) of damp can sometimes be difficult to determine and may have more than one source.”
• “SOURCE: Government”
• “Severe condensation is more common than rising or penetrating damp.”
• “URL:” Source
• “QUOTED LINE: "The most common form of damp was severe condensation (3%), which was more prevalent than rising damp (1%) or penetrating damp (2%).”
• “SOURCE: Government”
• “Inadequate ventilation is strongly associated with damp.”
• “URL:” Source
• “QUOTED LINE: "1% of dwellings had inadequate ventilation, of which 60% had a problem with damp.”
• “SOURCE: Government”
• “The 2024–25 damp figure is 1.4 million dwellings, 5%.”
• “URL:” Source
• “QUOTED LINE: "There were 1.4 million dwellings (5%) that had a problem with damp in 2024”
• “SOURCE: Government”
• “Awaab’s Law applies to social housing, not private landlords.”
• “URL:” Source
• “QUOTED LINE: "Awaab's Law applies to almost all social housing occupied under a tenancy and let by a registered provider.”
• “SOURCE: Government”
• “The “12 weeks” Awaab’s Law period is a deadline to begin supplementary preventative work.”
• “URL:” Source
• “QUOTED LINE: "the lessor must secure that the relevant supplementary preventative work begins—(a)as soon as reasonably practicable, but (b)before the end of the period of 12 weeks”
• “SOURCE: Government”
• “No law yet imposes Awaab’s Law timescales on private landlords.”
• “URL:” Source
• “QUOTED LINE: "We will carefully consider how best to apply Awaab's Law to the private rented sector in a way that is fair, proportionate and effective for both tenants and landlords, and will consult on this.”
• “SOURCE: Government”
• “Mould enforcement can run through an improvement notice capped at £40,000.”
• “URL:” Source
• “QUOTED LINE: "The amount of a financial penalty imposed under this section is to be determined by the local housing authority, but must not be more than £40,000.”
• “SOURCE: Government”
• “Recurrence requires further investigation.”
• “URL:” Source
• “QUOTED LINE: "If damp and mould have reappeared, further investigation and intervention should be pursued”
• “SOURCE: Government”
• “Social-housing works under Awaab’s Law are aimed at making the home safe and preventing recurrence.”
• “URL:” Source
• “QUOTED LINE: "that is necessary in order to—(i) make the home safe, and (ii) ensure, so far as is possible, that the hazard in question does not recur”
• “SOURCE: Government”
• “The Housing Ombudsman benchmark is follow-up visits for at least a year.”
• “URL:” Source
• “QUOTED LINE: "It would also be good practice for landlords to schedule follow up visits at set periods, for at least a year after works are completed, to satisfy themselves that the problem has not returned.”
• “SOURCE: Government/regulator”