Condensation: you can’t always see it, but it’s always there. The average family produces up to 14 litres of water vapour per day, which poses the question – how much condensation is too much condensation? Read on to find out what causes condensation problems in your home and roof space and what you can do to prevent them.
What Causes Condensation?
Condensation is the process of water vapour in the air changing into liquid. It happens in humid environments or when warm air hits cold surfaces; in the home, too much moisture in the air or warm air rising toward a cool loft can cause condensation problems in the roof space.
If left alone, condensation can cause more severe issues like dampness and mould. Damp and mould have health implications for those with asthma and other respiratory conditions, so it’s essential to know how to prevent and treat condensation. There are several causes of condensation in the roof space. Let’s delve into some of the most common ones:
Hot Water Tanks
Many families store hot water tanks and boilers in their loft space, which can prove problematic because of the heat they give off. Usually, loft spaces are uninhabited and often the coldest area of a house, creating the perfect environment for condensation.
The benefits of loft insulation are well known: it reduces heat loss from the roof, meaning your home feels warmer in the winter and your energy efficiency improves. However, ceiling insulation can cause condensation in your loft as it prevents air circulation, meaning excess moisture in the air condenses against the cold loft surfaces because it cannot escape.
It’s common for families to use their loft space as storage, which can mean over-filling it. Over-crowding with possessions decreases ventilation, therefore condensation occurs on cold surfaces like dormer windows.
Ventilation is affected by loft insulation, overcrowding, and inadequate roof ventilation. Older houses may not have sufficient vents; thankfully, modern homes tend to have ventilation installed along ridges or eaves, improving airflow and allowing excess moisture to escape.
Poorly Fitted Hatches
Ill-fitted or uninsulated loft hatches allow moist air from the rest of the house to rise into the colder loft environment and form condensation on any cold surface in the roof cavity.
Unfortunately, day-to-day activities in modern life create a great deal of water vapour! Everyday activities like taking hot showers and baths, drying clothes, and boiling kettles contribute to roof condensation issues by producing warm, humid air that rises to the loft.
Problems Caused by Condensation
Signs of condensation issues in roof spaces often go unrecognised for some time because lofts often aren’t used daily. Be sure to look out for the following tell-tale signs of roof condensation problems:
- Damp patches in your loft space
- Water on the underside of the roof membrane
- Black spots/mould on ceilings
- Mould spores on clothes or soft furnishings
These are some of the visible signs of condensation problems in your home. Condensation can also cause structural damage, including dry rot. Left unchecked, issues like these can cause major headaches for homeowners, so it’s vital to get them checked out before further problems arise.
What To Do About Condensation Problems
Condensation can occur year-round, though it is more common in the colder months of Autumn and Winter when your house is likely to be warmer, and windows stay closed. Efficient ventilation is the key to minimising roof condensation problems. Opening windows is the first step to increasing airflow and ensuring there is enough air in your house. Follow on for some more solutions to condensation issues.
Installing extractor fans in bathrooms and kitchens ventilates homes and contributes to the eradication of condensation by circulating air and getting rid of moisture. Extractor fans spin to create a vacuum, drawing water from the air and expelling it outside the house.
Ventilation vs Insulation
Often, condensation occurs because of an imbalance between ventilation and insulation in the roof cavity. It’s crucial to add roof ventilation as and when you improve your loft insulation, so that warm air has a place to escape.
If your attic space is overcrowded, the chances are your possessions could be blocking existing vents. Ensure nothing is covering roof vents, and move storage boxes at least 5-10cm away from walls so that nothing is damaged if there is condensation in your loft.
Damp clothes on radiators create moisture-laden air that rises to the top of a house and causes condensation in your loft space. When possible, dry clothes outside to avoid dampness and mould in your home.
Simple but effective! Even in winter, when it’s tempting to batten down the hatches, try to keep windows ajar to improve ventilation in your home.
Replace Old Roof Felt
Older homes often have felt roofs that don’t allow moisture to pass through and escape the roof cavity. Replace old materials with roof membrane to improve ventilation.
Preventing condensation in your home
Adequate ventilation is the key to conquering a condensation problem in your roof space, and there are many ways to achieve improved airflow. If your loft is poorly insulated and has inadequate ventilation, excessive moisture will linger in the air to form condensation, so the first step is to improve roof ventilation.
Other than lifestyle changes like taking cooler showers and switching on extractor fans when cooking, one of the leading solutions to a condensation problem is installing an improved roof membrane. Remember to check your loft for signs of condensation issues regularly, and it also may be worthwhile shopping around for more effective insulation.