Selling a house with damp and black mould issues

Black mould is usually the result of too much moisture in your house. This can be caused by a variety of reasons, including poor ventilation, leaks, rising damp and penetrating damp.

Once mould spores find a damp, poorly ventilated spot, they spread quickly and leave black patches on walls, ceilings and even furniture.

If you are interested on things that will devalue your house you can also read our dedicated guide.

In some cases, yes, black mould can be dangerous. Mould spores can trigger health problems, particularly for children, the elderly or anyone with asthma, allergies or weakened immune systems. Look out for eye, nose and throat irritation, skin rashes and worsened asthma attacks.

Even for healthy adults, long-term exposure can be unpleasant. Once you combine this with how unsightly mould is, you end up with unwanted extra challenges in selling your home.

In minor cases, you can manage the mould through cleaning, ventilating and dehumidifiers. But, if the mould has taken over large areas , it can impact both your health and quality of life. Not only is it recommended to vacate the house, but it also makes it a hassle to sell.

Yes, you can, but it will affect what buyers think of your property and they’ll likely lower the offers you receive.

Yes. Sellers are legally required to disclose any issues that could influence a buyer’s decision, and mould counts as one of these issues. If you fail to declare it and the buyer discovers the problem later, you could face legal action.

No, it’s not illegal. However, selling without disclosure could land you in serious trouble, as buyers have a right to know about anything that might affect the property’s value or their decision to purchase.

There’s no exact figure, but damp and mould can reduce a home’s value by 10– 20%. Buyers often factor in:

• The cost of professional damp treatment
• Replastering or redecorating
• Temporary accommodation during repairs
• The hassle of mould coming back

If your property has a severe or well-known mould issue, the hit to your sale price could be even higher.

Yes, it can be. Some buyers will walk away immediately when they hear “damp” or “mould”. Others may use it as leverage to negotiate a lower price. Lenders can also be cautious, as damp problems often show up on surveys, potentially delaying or collapsing the sale.

If you want to sell on the open market, you may need to:

• Pay for costly treatments – expect to pay around £5,000 for damp proofing
• Wait for remedial work to be completed
• Accept a lower offer
• Disclose the issue to every potential buyer

For many homeowners, that’s frustrating if they’re looking for a clean break.