Damp and mould in a rented flat: how to report it, what to record and what to ask for

The heating is back on, the windows stay shut and the laundry dries indoors. For many tenants, this is when the first grey-black spots show up in a bedroom corner or behind the wardrobe. Mould is unpleasant, it can affect your health, and it often turns into an argument about whose fault it is. That argument can still be going on when you move out and ask for your deposit back.

This guide is for tenants anywhere in Europe. It covers how to work out what is causing the problem, what you can sensibly do yourself, and how to report it so you are protected. It starts with a piece of UK news from this week that shows where the rules are heading.

The news: Scotland now sets deadlines for damp and mould

On 6 October 2026, Scotland's version of Awaab's Law came into force. It is named after Awaab Ishak, a two-year-old who died in 2020 after long exposure to mould in his family's flat in England. The Scottish rules cover private landlords as well as social landlords. According to the Scottish Government's guidance and legal summaries, once a landlord knows about damp or mould:

• a competent person must investigate within 10 working days;
• the tenant must get a written summary of the findings within 3 working days after that;
• if work is needed to keep the home substantially free from damp and mould, the repair must start within 5 working days of the investigation;
• if a deadline can't be met, the landlord must explain why in writing and give a new timescale.

The landlord is not responsible for everything. Where mould comes from the home not being adequately aired and heated, the guidance accepts that responsibility may not lie with the landlord. If a Scottish tenant and landlord can't agree, the tenant can take the matter to the First-tier Tribunal (Housing and Property Chamber).

England is not there yet. On 8 October 2026 the UK government announced a consultation on extending Awaab's Law to private rented homes. It is open until 18 December 2026. For now these are proposals only, with no start date and no final deadlines. In England, Awaab's Law currently applies to social housing.

If you rent anywhere else, none of these deadlines apply to you. The underlying idea still does, though: report in writing, get a response within a reasonable time, and have a record of both.

Condensation or a building defect?

This is the question everything else depends on. As a rough guide:

Signs of condensation (everyday moisture with nowhere to go):

• water droplets on windows and cold walls, especially in the morning;
• mould in corners, on outside walls, behind furniture, around window frames and in bathrooms;
• it gets worse in cold weather and when laundry dries indoors;
• it often improves quickly with better airing and steadier heating.

Signs of a defect (water coming from somewhere it shouldn't):

• a damp patch that keeps growing, has a tide-mark edge or appears after rain;
• damp low on the wall, rising from the floor (possible rising damp);
• stains below a bathroom or flat upstairs, or near pipes (a leak);
• damp in a warm, well-ventilated room;
• crumbling plaster, peeling wallpaper or a musty smell that airing doesn't fix;
• extractor fans or window vents that are missing or don't work.

The line isn't always clear. Poor insulation or a thermal bridge (a cold spot in the structure, such as a concrete beam or a corner) can cause condensation mould even when you air the flat properly. That is a building problem as much as a lifestyle one. If you aren't sure, say so in your report and ask the landlord to have it checked.

Reasonable airing and heating habits

These habits help in most flats and also show that you have done your part:

1. Air briefly and fully. Open windows wide for 5–10 minutes a few times a day, ideally with a cross draught. This works better than leaving a window on the latch all day in winter.
2. Heat steadily. Don't let rooms get very cold. Cold walls collect moisture. A rarely used bedroom with the heating off is a classic mould spot.
3. Deal with moisture at the source. Put lids on pans, use the extractor fan, shut the bathroom door after a shower and air the room afterwards.
4. Dry laundry carefully. If you have to dry it indoors, use a room with the door shut and the window slightly open, or a dehumidifier.
5. Leave a gap. Keep wardrobes and sofas a few centimetres away from outside walls.
6. Measure. A cheap hygrometer helps a lot. Indoor humidity that stays above about 60% is a warning sign. Make a note of the readings, because they make useful evidence.

If heating costs worry you, mention it to the landlord. Some homes are simply expensive to keep warm, and that is part of the discussion.

Report it in writing, early

A quick word on the stairs is easily forgotten. A written report is not. Send it as soon as you notice mould, while it is still small.

A good report includes:

• where the problem is (room, wall, approximate size);
• when you first noticed it, and whether it is spreading;
• what you have already done (airing, heating, cleaning, humidity readings);
• dated photos, with something in the frame for scale;
• a clear request, for example: "Please arrange for someone to inspect the cause and let me know what you plan to do and when."

Use email, a messaging channel you both agreed on, or a letter, so there is a timestamp. If your landlord uses LeasingTrack, you can report the issue and message them on your lease, and it stays with the property's records for both of you.

Keep a simple log

Start a note or spreadsheet and add to it every week or two:

Take photos from the same angle each time so the change is easy to see. Keep copies of all messages. Also keep damaged belongings, or at least photograph them, before you throw them away.

What you can reasonably ask for

The details depend on your country and your contract, but these requests are reasonable almost anywhere:

• an inspection of the cause by the landlord or a competent tradesperson;
• a repair if there is a leak, faulty ventilation, broken guttering or a similar defect;
• working ventilation, such as extractor fans and window vents;
• advice or equipment if the problem is borderline, for example a dehumidifier while the cause is sorted out;
• a written answer about what will be done and when.

In many countries, serious, long-lasting defects that affect how usable the home is can justify a rent reduction or other remedies. The rules vary a lot, though, and doing it wrong (for example, simply stopping payments) can put you in breach of the lease. Don't withhold rent on your own initiative. Get advice first.

Mould and your deposit

Many mould disputes only come to a head at move-out. The landlord sees stained walls and deducts the cost of repainting. The tenant says the flat was always damp. The person with the better records usually wins.

To protect yourself:

• check the move-in inventory and photos for any existing damp or mould;
• show with your reports and log that you flagged the problem in time and kept up reasonable airing and heating;
• clean surface mould as it appears (if it is safe to do so), so small spots don't become a big stain;
• at move-out, photograph every room and go through the handover together if you can.

This works for landlords too. A tenant who reports early saves you from bigger repairs, and a clear record makes a fair deposit decision much easier.

If nothing happens

This is where countries differ most. In Scotland it may mean the First-tier Tribunal. In England, it currently means the existing repair and local council routes. Elsewhere it could be a municipal housing office, a public health authority, a tenants' association, a consumer advice service, mediation or the courts.

Send one clear written reminder with a reasonable deadline first. If there is still no response, get local advice from a tenants' organisation, a legal aid service or a lawyer, and bring your log and photos. If you or a family member have health problems that you think are linked to the mould, see a doctor and keep a record of that too.

Most landlords want to fix damp. It damages their property as well. A calm, early, well-documented report is usually all it takes to get things moving.