Following my article last month regarding dampness in buildings, I received numerous phone calls regarding condensation and how to prevent it. Therefore this month I have decided to explain in more depth the causes of condensation and the action that can be taken to prevent it.

What is condensation?
Condensation starts as moisture in the air, usually produced by cooking, washing, or drying clothes on radiators. When this moist air hits cool surfaces such as walls, mirrors, wall tiles and windows it condenses and forms water droplets. Moist air rises when it is warm and often ends up on the ceilings.


Why is it a problem?
Left untreated, condensation can result in mould growth on walls, ceilings, furniture, furnishings, and clothing in cupboards and drawers. It can also affect wall plaster and cause windows and other woodwork to rot.

How to reduce condensation in your home

  • Firstly control excess moisture
  • Close kitchen and bathroom doors to prevent steam going into colder rooms.
  • When cooking or washing, let the steam escape by opening a window or using an extractor fan if you have one fitted. Leave the window open or the extractor fan on for at least 15 minutes after you have finished cooking or washing.
  • Open some windows in other rooms for a while each day and open any trickle vents in your window frames, this allows a change of air.
  • Wipe down surfaces when moisture settles to prevent mould forming.
  • Do not block air vents and allow air to circulate around furniture and cupboards.
  • Its wise not to use bottled gas or paraffin heaters – these produce a lot of moisture and they are also a health and safety risk.
  • Produce less moisture
  • Dry clothes outdoors whenever possible or use small ventilated rooms.
  • Cover pans when cooking.
  • If you have a tumble drier or washing machine, ensure that it is vented externally in accordance with the manufacturer’s instructions.
  • Keep your home warm
  • Insulation and draught proofing will keep your home warmer and will also cut fuel bills. When the whole house is warmer condensation is less likely to form.
  • Insulating your loft and walls will help however this is more difficult in older Spanish properties.
  • Maintain low background heating in the winter months even when you are not living there.
  • Consider installing secondary glazing or double glazed windows to reduce heat loss and draughts, if you decide to do this you must make sure that there is some ventilation in the room.

Some words of warning

  • Do not block permanent ventilators.
  • Do not completely block chimneys.
  • Do not draught proof rooms where there is already condensation or mould growth.
  • Do not draught proof a room where there is a gas cooker or a fuel-burning heater, for example a gas fire.
  • Do not draught proof windows in the bathroom or kitchen.
  • Do not put furniture against cold external walls.


Mould treatment

  • Treat any mould you may already have in your home and then do what you can to reduce condensation; this will restrict new mould growth.
  • Do not disturb mould by brushing or vacuum cleaning it; this can increase the risk of respiratory problems.
  • Do not wipe off mould growth with water - do not use washing up liquid.
  • To remove and kill mould growth, spray with a fungicidal foam cleaner, this is available from any hardware store or supermarket. Always follow the instructions carefully - do not use bleach.
  • Dry-clean clothes affected by mildew and shampoo carpets.
  • After treatment, if necessary redecorate any affected walls and ceilings using a good quality fungicidal paint to help prevent mould recurring.

John Phillips (F.I.A.S. F.A.B.E. M.I.B.C.O. F.F.B. M.R.S.H. C.M.W.O.B.O. M.B.I.M)
Construction Buena Vista

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Construction Buena Vista
Urb. Palmeria. Orba 03790


Please call us on


0034 965 577 464 (office)


0034 619 089 281 (mobile)


or use our contact form.



Buena Vista Villas s.l.

Urb. Palmeria. Orba 03790


Please call us on


0034 965 577 464 (office)


0034 629 554 561 (mobile)


Or simply click the image above