Causes of damp

Damp within a house or property is caused by one of the following 4 conditions.







Generally found in older properties with either a poor D.P.C. { damp proof course } or no D.P.C..  Period properties of over 1 hundred years construction generally are build on soil with little foundations. It was normal for a section of slate or granite to be laid as a form of D.P.C. and although effective at the time , with modern living, central heating , double glazed windows and insulation moisture is sucked up from below floor level.

Houses or properties  build in the 1960 or older have a bitumen{tar] damp proof course and are subject to cracks forming due to settlement of the building or stress cracks which may tear or break the moisture barrier allowing ingress of  moisture on external or internal walls.

Modern properties seldom suffer from this type of dampness, however care should be taken when altering openings i.e DOORS OR WINDOWS.

This form of  dampness is identified by checking below windows and in corners of ground floor rooms.  It will be visible and will appear as  a mark or stain which rises to the widow  cill or climbing up high into a corner.. It can be found on internal and external walls.

Any Stain on mark which is higher than 2 metres or 6 feet high is not from this form of dampness as moisture can not rise beyond this point on any surface.


TREATMENTS  consist mainly of chemically injected damp proof course and remedial plaster works and carry a 25 year guarantee.  For specifications look up Services section on main menu.

Basements or areas below ground level require specific treatments. For specifications look up services section of main menu.


This form of dampness is caused by poor or inadequate ventilation. Modern living and use of the space in a poor or ill informed manner.

The symptoms of this type of dampness are windows  and window frames condense with water gathering at the end of the window. In older properties with single glazing it is the warm moisture laden air meeting a cold surface and the windows will steam up.

More modern double glazed windows with metal / aluminum or dated u.p.v.c plastic window frames are fitted with a condensation or drip tray as part of their design. These trays or moisture channels are   10mm wide and designed with  1 mm holes in the frame to allow water formed from moisture condensation  drain away.  Over time these holes become blocked with dirt or dust and a simple clearing of these holes using a needle or pin frees the drain and allows water drain away.

Clothing or shoes in enclosed spaces like presses or wardrobes will start to get musty smelling and spores of mould will form.

Corners of rooms  either at floor lever /behind furniture or up high will begin to form Black mould or fungus. Fungus left untreated will spread to other areas of the room or property.

Black mould is identifiable as a black fungus which forms colonies. For more information please look up Black mould treatments in Services. This mould should be removed as soon as it becomes noticeable y means of a mould/ fungus remover or simply wiped with bleach. Gloves should be worn and the cleaning cloth placed in a sealed waste bag and disposed of in all instances.. For technical data and information please see services section under Toxic Black mould ..

Mildew or mould fungus is grey/ green in colour and has a distinctive smell. Leaving storage doors open a small amount and wiping with bleach will reduce the spread of mould.

Treatments.  A simple and effective way to alleviate condensation is to open windows when ever possible.

Air Vents should remain open and checked for blockages as in rented properties these can be blocked up for heat retention.

Adding extra air vents Into internal walls above doors and  external walls allows for air circulation.

Air vents can be adjustable or can be closed as required.

New double/triple glazed windows can be installed with trickle vents in the frames which will meet all  building / planning regulations in relation to air circulation/ ventilation.

DRYING wet / damp clothing within the property should be avoided at all times as the moisture released simply returns to water as soon as the air makes contact with any cold surface.

For Treatments see services section in main menu.



This form of dampness is restricted to the internal elevations of the outside walls.

It will be found in the centre of walls and unlike other forms of dampness does not hide in corners

Causes are generally poor or defective cement rendering, untreated structural cracks and poor or faulty pointing.

Poor / old or leaking gutters or down pipes are also contributing factors. Leaks or faults should be repaired as soon as noticed to reduce water damage on internal walls.

Untreated cracks allow rain water penetrate the walls and in freezing conditions the moisture forms ice within the crack. Freezing water exerts a pressure of 7.5 tonnes  per cubic centimeter causing the crack or fault to constantly get bigger allowing even more moisture through the wall.

Poor or faulty pointing of brick work on walls or chimneys allows wind to force moisture through the wall. The life of sand and cement is 100 years after which time the individual parts separate and allow the bricks become porous.


TREATMENTS. Re pointing of old brick properties is recommended. Cracks in walls filled and repaired.

Owners of older brick properties should be especially careful of chimney stacks as they are extremely exposed to the elements.

Walls can be treated with water repellant systems such as silicone water repellants or liquid aluminum in extreme cases.

For a range of treatments /  specifications please see services section in main menu.



Water leaks within a property or premises are the most damaging and costly of all forms of dampness.

Clearly identifiable in most cases as a circular stain on ceiling or walls.

Once identified the leak should be repaired as soon as possible to minimize damage.

It is the responsibility of the householder or landlord to repair or rectify a leak in order to minimize costs to the property insurer.

Once the problem is solved re decoration is a simple matter. Painting over the now dried brown stain with an oil based undercoat acts as a stain blocker allowing the finish coat be applied.

Untreated or unidentified leaks will result in the growth of black mould on both sides of any plaster board finish.  Please see Black mould treatments in main menu for treatment/ specifications.

A simple way to prevent or minimize leaks is to turn off water at the mains when going on holidays or leaving a property unattended for long periods.

Proper insulation of pipe works/ storage tanks and attic spaces is also important.  For specifications please see attic insulation in services section on main menu