Damp & Mould Compensation Calculator — How Much Could You Claim?
Updated 2026 · Based on Wallace v Manchester City Council [1998]
How damp claims are valued. Courts don't use a fixed tariff for housing disrepair. They award a proportion of the rent you paid while the property was in disrepair — the worse the effect on your use of the home, the higher the proportion. This calculator applies that method.
In this guide
- Damp & Mould Compensation Calculator
- How Much Compensation for Damp and Mould?
- How Courts Calculate Your Compensation
- What You Can Claim For
- How to Start a Housing Disrepair Claim
- Frequently Asked Questions
Damp & Mould Compensation Calculator
Estimate your claim in under a minute
Based on the percentage-of-rent method courts apply.
| Rent paid over period | £0 |
| General damages (0% of rent) | £0 |
| Simmons v Castle uplift (10%) | £0 |
| Special damages (belongings, heating, accommodation) | £0 |
| Estimated total | £0 |
Court tariff cross-check: £0 – £0 for 0 of disrepair (Wallace tariff of £1,264–£3,477 a year, uprated for inflation). Courts sanity-check percentage awards against this range.
Because you haven’t reported the problem yet, the claim period normally only starts once your landlord knows. Report it in writing now — that starts the clock even if the damp has been there for years.
This is an estimate, not a valuation. Your actual award depends on evidence — what you reported, when, and what your landlord did about it. Some claims do not succeed.
Read the housing disrepair guideHow Much Compensation for Damp and Mould?
There is no fixed tariff. In Wallace v Manchester City Council [1998] the Court of Appeal set out how damages for housing disrepair should be assessed, and the approach courts have used since is to award a proportion of the rent paid during the period of disrepair. The proportion reflects how much your use and enjoyment of the home was actually reduced.
| Severity | What it typically means | Share of rent |
|---|---|---|
| Minor | Damp or mould in one room, home still fully usable | 5–15% |
| Moderate | Several rooms affected, some rooms difficult to use | 15–30% |
| Serious | Rooms unusable, belongings damaged, health affected | 30–50% |
| Severe | Home substantially uninhabitable | 50–100% |
Be wary of sites quoting a flat "25% to 50%". That is the range for serious disrepair, not a typical case. Wallace itself indicates minor defects sit nearer 5–10% of rent. A calculator that starts at 25% will overstate most claims.
How Courts Calculate Your Compensation
Step 1 — The rent you paid
The starting point is the rent paid over the period the property was in disrepair. That period usually runs from the date your landlord knew about the problem, not the date it first appeared — which is why reporting it in writing matters so much.
Step 2 — The percentage reduction
The court decides what proportion of the value of your home you actually lost. A single damp patch in a spare room is a small fraction. A property you cannot heat, with mould through the bedrooms and children's belongings ruined, is a large one.
Step 3 — The 10% uplift
General damages in these claims attract a 10% uplift following Simmons v Castle. It applies to the damages for discomfort and inconvenience, not to your out-of-pocket costs.
Step 4 — Special damages
Anything you can evidence as an actual financial loss is claimed on top: damaged furniture, clothing and carpets, higher heating bills from trying to dry the property, the cost of staying elsewhere. Keep receipts and photographs.
The cross-check. Courts sanity-check the result against an annual figure. The tariff established in Wallace was £1,000 to £2,750 a year; uprated for inflation that is roughly £1,264 to £3,477 per year of disrepair. If a percentage calculation produces something wildly outside that, it usually gets adjusted.
What You Can Claim For
- Discomfort and inconvenience — living with damp, mould, cold or smell
- Damaged belongings — furniture, carpets, clothing, bedding, electricals
- Increased bills — heating and drying costs above the normal
- Alternative accommodation — if the property became unfit to live in
- Ill health — respiratory problems and similar, where medically evidenced. Note that a claim including personal injury has a three-year limit rather than six
How to Start a Housing Disrepair Claim
- Report it in writing. Email or letter, so there is a dated record. If you only ever reported it verbally, do it again in writing now.
- Photograph everything. Date-stamped images of the damp, the mould, and any damaged belongings. Keep taking them as it progresses.
- Keep the paper trail. Every reply, missed appointment and failed repair. This is what establishes how long your landlord has known.
- See a GP if your health is affected. Medical records are the difference between claiming for inconvenience and claiming for illness.
- Give your landlord a chance to fix it. A formal complaint first. If they don't resolve it, social housing tenants can escalate to the Housing Ombudsman free of charge.
You do not need to pay anyone to complain. Raising a formal complaint with your landlord is free, and escalating to the Housing Ombudsman is free. A solicitor becomes worthwhile when the landlord won't act, or when the claim is substantial.
Frequently Asked Questions
How far back can I claim for damp and mould?
Generally six years for a disrepair claim, because it is a breach of your tenancy agreement. If your claim includes personal injury — respiratory illness caused by mould, for example — that element has a three-year limit from when you knew about it. Act sooner rather than later either way, because evidence degrades.
What if I never reported the damp to my landlord?
It is much harder. Your landlord's repairing obligation under section 11 of the Landlord and Tenant Act 1985 generally bites once they know, or ought reasonably to know, about the problem. Without a report there is usually no clock running. Report it in writing now — that starts the period even if the damp has been there for years.
Can I claim if the damp is caused by condensation?
Possibly. Landlords often blame condensation on the tenant's lifestyle, but if it stems from a structural problem — failed damp proofing, inadequate ventilation, single glazing, poor insulation, a defect that makes the property impossible to heat — that is a disrepair issue. The Homes (Fitness for Human Habitation) Act 2018 also requires rented homes to be fit to live in, which covers damp and mould independently of who caused the moisture.
Will claiming get me evicted?
Retaliatory eviction protections exist, and a landlord who serves notice shortly after a legitimate disrepair complaint may find that notice invalid. If you are worried, take advice before you start — but the fear of eviction should not stop you reporting a home that is making you ill.
Can I claim if I'm in council or housing association property?
Yes. Social landlords have the same repairing obligations as private ones. You also have access to the Housing Ombudsman, which is free and can order a landlord to pay compensation without any court claim at all.
Do I have to move out to claim?
No. Most disrepair claims are brought by tenants still living in the property. Wallace confirmed that where you remain in occupation, what is being compensated is the discomfort and inconvenience you have endured — not a drop in the property's market value.
This calculator gives an indicative estimate only. It is not a valuation, an offer, or legal advice, and no outcome is guaranteed. Estimates are based on the approach to general damages set out in Wallace v Manchester City Council [1998], the 10% uplift in Simmons v Castle, and the Wallace annual tariff uprated for inflation. Actual awards vary considerably according to the evidence in each case, and some claims are unsuccessful. You are free to complain to your landlord and to the Housing Ombudsman without paying anyone. Claims Bible is a trading style of Forces Compare Ltd, registered in England and Wales (company no. 10345563), authorised and regulated by the Financial Conduct Authority in respect of regulated claims management activities, firm reference number 785329.
