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Finding a local damp surveyor

By Ruth MacEachern

Product Manager

Dec 04, 2023

Millions of homes in the UK suffer from damp, and more cases are discovered each year.  Aside from causing damage to the fabric of the building such as causing plaster to crumble, paint to peel, and wood to rot, damp can also lead to the growth of mould on walls and ceilings.  In some cases, mould can be very dangerous.  It can affect the health of residents, particularly the very young and those with immune system problems.

Surprisingly, in reality, the most common form of damp isn't from water leaking into the property through holes in walls or around windows (penetrating damp) or being drawn up from the ground (rising damp), most damp is due to a build-up of condensation from activities such as bathing or cooking.

In order to treat damp, the first step is to identify the cause of the problem.  Below you can find information about the different types of damp and how you can spot them in your home.

Three Main Types of Damp:

Penetrating Damp

Water leaking through walls or gaps in your home’s envelope is known as penetrating damp.  It is usually caused by structural problems in a building such defective roofing, guttering or brickwork, but it could also be due to a leaking pipe behind a wall or inside the ceiling cavity.

You can usually spot the source of penetrating damp problems due to watermarks that appear on the walls where the moisture is leaking in.  You might notice damaged plaster, powdery surfaces and blistering or bubbles appearing in your paint.  There will normally be a stain around the area where the damp is leaking through – this may be discoloured by the pigment in your plaster or from contaminants picked up by the water above ceilings.

Rising Damp

Rising damp is caused by ground water being drawn up into the walls of your home by capillary action.  Essentially, the wall behaves like a sponge and soaks up the water from the ground.

Damp patches more than about a metre above the ground level are unlikely to be due to rising damp as there is a limit to the height above the ground that water can be drawn into your walls. 

Rising damp normally presents as large patches up to about 1 metre above floor level on the ground floor of your property.  The damage will usually start around skirting boards.  Paint may become discoloured as a result of the underlying plaster, and wallpaper may peel away from the wall.  Mould can start to colonise damp walls quickly particularly in areas with poor airflow such as cupboards.

A damp proof course is a protective barrier that is installed when walls are built.  If this is missing or has become damaged, then the walls may start to suffer from rising damp, and you should seek assistance from a damp proofing surveyor.

Condensation Damp

Condensation damp is by far the most common form of dampness found in UK homes.  Rather than water entering the property from outside, condensation damp is caused by high levels of moisture in the air indoors – this usually comes from cooking, cleaning, washing and even breathing.

When warm, humid air comes into contact with cold surfaces, the water vapour is released and forms condensation on the walls, windows or ceilings.  If the moisture condenses on a porous surface such as a wall, it can soak in to create a damp patch that will grow over time.

What usually starts off as water droplets on windows and walls can soon turn to streaming windows and mould growth. The problem can quickly spread throughout a property and can cause serious damage to the structure.

As with other types of damp, if condensation damp is not dealt with, it will create the perfect environment for mould to grow which can damage your health.

>> Find out how to stop condensation in your home

Stopping damp

Both rising and penetrating damp will usually need to be dealt through repairs to your home – fixing holes, resetting the damp proof course, and then redecorating the affected areas.  With condensation damp, the solution is usually to improve the ventilation in “wet” rooms such as bathrooms and kitchens to reduce the humidity levels.  This can be achieved with either extractor fans that run automatically, or through a whole house ventilation system that will displace the humid air.

If you need further help to identify the source of the problem or you would like to speak to a local surveyor to discuss your problems and get advice, then call 0345 27 27 807.

Find out more

If you are concerned about a patch of damp in your home, or are having issues with condensation, we can help.  Contact us today to book a free home survey from a local ventilation specialist.  We can visit your home to identify the causes of condensation and provide advice about the best solution for your needs.  Simply enter your postcode below to find an expert near you.

Need help with condensation, mould or damp problems?

One of our local experts will contact you to learn more about your problems, offer free expert advice and make recommendations for a permanent solution.

During the free survey we will

  • check Assess any condensation, damp or mould problems in your property
  • check Take readings of the relative humidity levels
  • check Identify any underlying problems and make recommendations for a permanent solution

Arrange a FREE Home Survey now