EDITION: December - February 2013

What can be done about dampness in the home?

Texto: Christine Lendt
With the arrival of the winter season in Ibiza, the worries of many house-owners also return over the dampness that causes structural damages to buildings, leaves ugly marks and can also affect your health with ailments as rheumatic pains or allergies and respiratory illnesses due to mouldy walls. Old houses tend to be particularly affected… But dampness can appear also in new constructions, since it has several causes.

Ascending dampness

In older buildings, ascending dampness is a frequent problem. It appears when the dampness in the ground infiltrates the walls, since most building materials are porous. These pores literally absorb water from below, saturating walls with water, just like petrol ascends in the wick of a lamp. The degree of infiltration will depend on the size of the pores of the masonry, of the quality of the paint and also of the degree of humidity in the ground. The maximum height is normally of 1.5 metres. This dampness is also the cause of cold walls, of rendering and plastering peeling off, and of the appearance of those pesky moulds.

When there are leaks in the house

Another cause for dampness is quite simply the rain. If the coating is faulty, water will penetrate directly to the masonry. Often eaves are not sufficient. Water can also filter through faulty drains and broken pipes. Exterior coatings that are in direct contact with the ground also absorb and are impregnated with salts and damp. In Ibiza, flat roofs always give problems, since rainwater accumulates and stagnates. If the roof has not been water-proofed, things get even worse... Experts recommend water-proofing roofs with rubber, as a preventive measure. You can also help to avoid leaks by regularly checking and cleaning the drains on roofs – they often get covered up by pine leaves.

In the case of roofs, like walls, windows or other installations: the most insignificant damages can have serious consequences, as water drops wear down stone, and over time the amount of water that filters even through tiny cracks, permeable joints or faulty exterior paint coverings, increases. An outdoor paint with a specialised product will also prevent the filtration of dampness. In a new construction, waterproofing materials should be used from the start.

Condensated water in the living room

Condensated water forms when warm, damp air comes into contact with a colder surface. The humidity in the air condensates and falls, like morning dew in the countryside. Only in a house this image is a lot less romantic. In the last decades, the damages thus caused have increased considerably.

The reason is that condensation water tends to appear after reforms have been made. Old, permeable windows, for example, provide sufficient exit for water vapour. However after installing new windows, dampness can no longer exit the room. In this case, you should air the room more, especially after showering or cooking. Another trick is to dry your clothes outside or in a dryer, since damp clothes within the house are also an important source of dampness by condensation.

Expert advice

In order to reach an exact diagnosis regarding dampness in a house, it is advisable to call in a competent technician who, based on different analyses, can advise you on what actions to take. However, you can contribute yourself to preventing problems, for example installing electric de-humidifiers. It is very important to air and heat a house correctly.

“ Sudden ventilation” is proven to be very effective: throw all windows wide open, a few times a day, for five or ten minutes. The air current allows for a quick exchange of the warm damp air inside without cooling down furniture and inner walls too much.

As for heating, the exact opposite is true:

it is better to heat continually at low temperatures than to turn the heating on at maximum for a short time, because if you turn off the heating during the day while you are out, you will find a cold house when you get home at night. If you then turn on the heating at full blast you will heat only the air, whereas the walls will continue to be cold, provoking a condensation of the dampness in the room, which is precisely what we should aim to avoid.