Condensation accounts for about 75% of reported domestic damp and is undoubtedly a contributing cause of some infestation by wood boring beetle and dry rot outbreaks.
Condensation can commonly be attributed to a lack of balance between heating and ventilation, resulting in a rise in relative humidity. Air can hold more water vapour when warm than cold.As Warm air is cooled, such as when the heating is switched off at night, it will deposit the water that it can no longer retain as condensation on a cold surface. A similar effect can be demonstrated by breathing onto a mirror or other cool surfaces.
An average family of 4 people can produce up to 16 litres of water a day. This can be from drying wet clothes on radiators,using an unvented tumble dryer, hot baths or showers, boiling kettles, cooking and of course breathing. That’s a lot ofwater vapour being stored by the warm air in a typical centrally heated, doubled glazed home. When the evenings are chilly and the heating goes off at night the air temperature inside the home drops. Cool air cannot retain the same amount of water vapour as warm air and so when the warm air comes into contact with a colder surface such as an outside wall or window, it will deposit the moisture it cannot hold onto that surface which causes misted or streaming windows, and in extreme cases walls that are wet to the touch and black mould growth.
How to Reduce Condensation
- Ensure that your property is well heated to 21 C
- Ensure that you have adequate ventilation via extraction fans in bathrooms and kitchens and keeping window trickle vents open.
- Use a dehumidifier which will reduce humidity and condensation
- Install 'positive input ventilation', a low energy system which ventilates the whole home from its location in the loft-space or hallway, and creates an environment in which condensation and mould growth can’t exist. This type of ventilation is the most effective method of preventing condensation, reducing dust mite allergens and generally improving the indoor air quality.
Our surveyors at Ambient Preservation can advise on the best method of reducing or eliminating condensation in your home.
An alternative to heating and ventilation for the control of moisture in the air is a dehumidifier. This is a device which draws in air, cools it to remove moisture which is collected in a reservoir and reheats it to an acceptable temperature before re-circulating it. The disadvantages of using dehumidifiers are that you need one in each room if doors are closed and the running costs are about 20p/day for a 12 litre/day dehumidifier.
Other devices that may be considered are positive pressure condensation control units. These often take dryer air from roof spaces or lofts and mix this with air in the dwelling. This is done at a very low rate (below half an air change per hour) and has the effect of lowering total moisture content and removing moist air by natural leakage.
We recommend installing Drimaster Positive Air Ventilation units.The Drimaster offers cost-effective ventilation for the whole property using the tried and tested Positive Input Ventilation (PIV) principle, where fresh, filtered air is introduced into the home at a continuous rate, encouraging movement of air from inside to outside. This process removes condensation, allergens such as dust mites, and the pollutants caused by cooking and cleaning from the air. The results are a fresh and healthy indoor environment in which condensation and mould cannot exist, and where indoor pollutants including harmful Radon gas are kept to a minimum - all great news for allergy sufferers.
The Drimaster is a low-energy whole home ventilation and cheap to run. Fitted in the loft, out of site and with no holes to knock through walls, the non-disruptive installation makes it an ideal solution for retro-fit projects. We would be pleased to give you a free quotation to install this system.
Features & Benefits:
Cures condensation dampness - PIV removes humidity from the air, preventing mould growth and controlling dust-mite allergens.
Improves indoor air quality - indoor pollutants from cooking and cleaning are removed while outdoor pollutants including traffic fumes, pollen and Radon gas are kept out.
Meets Regulations - meets Part F & L of Building Regulations as a low-energy ventilation strategy.
Extremely low power consumption - costs around 1p per day.
Easy installation and very low maintenance - filter clean or replacement every five years
Fixed heat recovery - minimises loss of heat in the loft by recirculating the air, saving energy.
System standby in summer months - when the loft temperature exceeds 23°C.
Health benefits - clinically proven to help allergy and asthma sufferers.
5 year warranty - for peace of mind.