Damp Survey Guide: When It's Crucial for Your Home

Damp is the presence of unwanted water or moisture in a building which, if it goes untreated, can cause structural damage. Damp is a major problem in the UK – creating cold and unhealthy living conditions in tens of thousands of homes.

Prevalent damp can have health implications, so if you think you may have a damp problem in your house it is important you get a surveyor to investigate and suggest the next steps to take.

The Types of Damp

Rising Damp

Causes	Identification
Water from the ground moving upwards through the brickwork in the wall of a property	A ‘tide mark’ on the affected wall, damaged skirting boards and floorboards, crumbling plaster and peeling wallpaper

Rising damp can often be misdiagnosed, so ensure that you are getting independent advice from an expert damp surveyor.

Penetrating Damp (Rain Penetration)

Causes	Identification
Water leaking through the walls, usually through cracks in the masonry	Damp patches on walls, floors and ceilings

Penetrating damp most commonly occurs in older buildings with solid walls.

Condensation

Causes	Identification
Moist water vapour condensing on walls	Water droplets on walls, damaged plaster and paint and decaying window frames

Damp caused by condensation is the most common type of damp occurring in homes and in the UK. It is particularly a problem between October and March – ‘The Condensation Season’.

Health Risks

The most common health complaints triggered by damp are asthma and other respiratory problems, which is due to the poor indoor air quality and the emission and subsequent inhalation of the mould spores damp causes.
The mould can also cause infections and immunological illnesses with prolonged exposure.

The dampness provides a thriving environment for bacteria to multiply, and with bacteria being a source for the transmission of disease this can cause health risks.

Damage to Property

The damage caused by damp is more than just aesthetic. It can lead to the structural deterioration of plaster and brickwork, rotting of timber frames, and the rusting of steel and iron fasteners.

If it’s left untreated the damage can be costly to repair and due to the nature of the damage caused by damp, it is likely that replastering and redecoration will be needed – a further expense.

Treatment

Each type of damp has a different treatment to control the problem.
To diagnose which kind of damp is affecting your home a damp survey will need to be completed.
Inappropriate damp treatment can be both expensive and potentially cause further damage to buildings, so it’s important to ensure you’re getting expert advice from a professional damp surveyor.

Type of damp	Treatment
Rising damp	Remove contamination, install a damp proof course
Penetrating damp	Identity and eliminate source of moisture using masonry protection paint or cream.
Condensation	Treat the mould and improve ventilation, insulation, and air circulation to prevent reoccurrence.

How much does it cost to treat damp?

It can cost anywhere from £500-£6000 to treat damp depending on the type and severity of the damp and the treatment needed.

How to know if you need a Damp survey

If you’re buying a property be sure to get a Surveyor to carry out a building survey to make you aware if there is a damp problem that would need further investigation from an industry specialist. This will give you an opportunity to reopen price negotiations with the seller or possibly reconsider your purchase.

The kind of survey you get will depend on the age and type of the property, so make sure to look up what type of survey you need.

How does a damp survey work?

While a general property survey will identify a damp problem, your surveyor will then suggest you get a damp survey, to determine the full extent of the damp and the appropriate method of treatment .
 
An approved damp surveyor should be CSTDB (Certificated Surveyor of Timber & Dampness in Buildings) qualified, and have a CRDS (Certificate in Remedial Damp Surveying) or a CSRT (Certificate in Remedial Treatment), so make sure you don’t use an under-qualified or under insured trader.

How do surveyors identify the damp?

The damp surveyor will use specialised tools such as a damp meter to inspect the property and determine the kind of damp present as well as what is causing it.

After their survey they will send you a report detailing all their findings and what needs to be done to the property to fix the issue.

How much does a damp survey cost?

Much like any building survey, a damp survey does not have a fixed price and will vary depending on the size and location of the property.
 
Typically, a damp survey from a qualified surveyor will cost between £200-£600.

Your building surveyor may recommend someone to carry out the survey, but as always, we recommend comparing other surveyors to find the best option for you.
 
Damp can cause serious damage, to both your property and your health, so if you have any concerns about damp in your home, get an independent surveyor to advise you on whether you need a damp survey.

Damp-proofing infographic

View this helpful damp-proofing infographic, courtesy of Wise Property Care to help you understand and identify the types of damp.

Damp survey guide FAQs

Is damp covered by insurance?

Home insurance does not usually cover damage due to damp. However, some insurers may offer special cover for damp.

Do you have to disclose damp when selling a house?

Yes, as with any known issue you must legally disclose damp when selling a property. If you do not disclose this and it is later proven that this was a known issue, then the buyer may take legal action against you.

Can damp decrease the value of a house? 

Damp can definitely have an impact on the value of a property. The amount that damp will devalue a property can range from 10%-53% and will depend on the severity and extent of the problem and its impact on the structure of the building