Understanding damp and mould
Damp and mould is a common problem area regardless of the age of your holiday home. It’s important to understand the causes and best ways to prevent the problems from worsening. We hope this article will help provide some understanding of the causes and what you can do to overcome/control damp and condensation.
Condensation occurs in your holiday home when the warm moist air from activities such as showering or cooking meets a cold surface such as an external wall or window. The moisture from these activities will remain in the air unless the room/s are ventilated and this moisture will find the nearest cold surface where it condenses. There is a natural amount of moisture in the air and when the air temperature drops this moisture will release this water in the form of droplets. This is known as the dew point.
Condensation generally occurs during cold spells of weather. It will appear on cold surfaces and also in areas where there is little movement such as behind a cupboard and will often lead to mould growth. The most common areas for this to occur are and in corners of rooms, in cupboards or on north facing walls, as these are generally the coldest areas.
Common causes of condensation
Lack of insulation
Insulation causes a warming effect which helps to counteract the conditions under which condensation can develop.
Cold spots/Thermal bridging
Cold spots occur in properties (generally older properties) where there is a direct connection between the inside of the building and outside through various materials. As a result the internal surface temperature of materials will be different which will cause condensation where the warm moist air comes into contact with the colder surface.
Lack of ventilation
Condensation can be controlled in part by increasing ventilation to let the moisture laden air to escape.
How to avoid condensation
With the correct balance of heating and ventilation, condensation should be avoided. The heating helps keep the property warm and the ventilation will enable excess moisture laden air to escape.
Set the heating using your thermostat on for long periods on a low setting or have it switched to operate automatically on shorter periods for at least seven hours a day. Do not adjust the thermostat manually when set but trust the system to regulate itself for you. Make sure there are no cold zones in your holiday home by making sure all the radiators are switched on.
How to prevent moisture
- Cover saucepans when cooking.
- Dry clothing outside rather than on radiators.
- Wipe away condensation as quickly as it’s spotted.
- Keep window trickle vents open constantly and open windows as much as possible (especially after cooking or showering) to allow a flow of air whilst maintaining a heat balance.
How much moisture is typically produced in the home?
- Drying clothes produces ten pints of water in an unvented tumble dryer.
- Having a bath produces two pints of moisture.
- Washing clothes produces one pint of moisture.
How to prevent mould
- Remove mould growth by wiping down walls and windows with a fungicidal wash recognised by a Health and Safety Executive. Dry clean mildewed fabrics and shampoo carpets.
- After treatment, redecorate using a good quality fungicidal paint to help prevent mould recurring.
- Ensure insulation to external walls is in place
Could damp be caused by something else?
Condensation may not be the only factor when mould growth occurs and below are some common causes of damp;
Rising damp – Occurs if the damp proof course or membrane within the walls or floors of your holiday home has failed.
Penetrating damp – Occurs when water seeps through cracks in brick/stonework, pointing or through missing tiles on external roof surfaces.
Blocked guttering – Will cause water to overspill and saturate external walls.
External plumbing – If cracked this could allow water seepage into internal parts.
It can be difficult to be certain of the exact cause of any dampness and so unless you are sure of the cause it may be wise to contact an RICS qualified surveyor or an experienced contractor who has experience working in this particular area for advice.
If you have found this article useful and would like some further advice on your holiday let please call George or Charmian on 01208 827 000 or email firstname.lastname@example.org.