Common causes of damp in the winter and how to prevent it
As we enter the cold, winter months, it is tempting to turn the heating on full blast and shut all windows and doors, aiming to lock heat inside the home and block out any winter chill. As a result, the moisture in the air has nowhere to escape to, which may cause it to condense on the cold surfaces of the home, such as the walls, ceilings, and skirting boards.
Heating your home during winter often causes difficulties, such as increased energy bills and heat loss in the home. We often do not account for damp and mould as part of this equation, but they are factors that are worsened by a lack of insulation, limited ventilation, incorrect use of heating, and more. In this article we will explore the causes of damp and mould, and how to help reduce them becoming a problem this winter.
If you have damp in your home, it is important to be aware that one, or many, potential causes could be creating it (i.e. drying clothes on radiators without ventilation in the property or the vents being blocked or covered). To treat the damp, you will need to identify which factor is causing it.
“Did you know?
A damp home will typically take twice as long to heat due to the air being much heavier – meaning, you can expect to see significant rises with your energy bills.’ (Eco home insulation)”
What is damp and how does it lead to mould?
‘Damp’ means that there is excess moisture in a building, causing wet spots on the surfaces which you can often see or feel. These damp areas—like walls, ceilings, and floors—provide moisture that mould spores need to survive and multiply. Over time, as the dampness persists, mould can spread, leading to potential health issues and damage to the building's structure. Common signs to spot are the little black spots which can be found on windows, walls, skirting boards and ceilings. You can often wipe these spots away on the surface, but this does not eliminate the mould spores that are buried in the fabric of your wall. To eliminate mould, you must eliminate the damp conditions in which mould thrives and properly identify the cause of the damp.
There are different types of damp and different ways to treat it…
Condensation damp
Condensation is a typical cause of damp in the home. When moist air lands on cold surfaces in the home, it condenses leaving damp spots. By just going about our day-to-day lives, we increase moisture in the air; for example, showering, cooking, drying washing, bathing, and breathing make the air moister.
It is important to consider how we can reduce the creation of excess moisture, such as taking shorter showers, using lids on pans when cooking, and drying washing outdoors rather than on inside surfaces and radiators. However, above all, it is important to consider ventilation.
Proper ventilation ensures that moisture can leave your home, whilst keeping it warm and properly heated. This means installing and using vents, extractor fans and trickle vents, as well as opening windows where possible.
Top tips to check ventilation:
Check that vents and airbricks are not blocked – check that outside the property, nothing is blocking the moist air from escaping. In rooms that are frequently used or have a source of moisture (shower, cooker etc.), regularly open the windows and make sure that the trickle vents are down. You can leave the windows open on the safety latch.
If damp gathers behind furniture, move it away from the wall to allow air to circulate
Check that extractor fans are clean and working to their full potential
Use a humidity meter (hygrometer) to test which rooms have the highest moisture and determine which need to be ventilated
A dehumidifier can reduce the amount of moisture in a room and help you identify which rooms are creating the most moisture, however, this is not recommended as a long-term solution. While dehumidifiers can improve living conditions, they do not address what is causing the moisture to build up. In addition, they can become an extra cost to run.
Ventilating well but still struggling with damp? Lack of proper insulation could be the problem:
Cold, improperly insulated surfaces can exacerbate dampness, including poor loft insulation, wall insulation, single-glazed windows, and insufficient heating systems.
Single glazed windows are much colder than double glazed windows, therefore they attract a higher rate of condensation. This is because double glazed windows have a gap between the panes of glass which acts as a thermal barrier. Where possible, double glazing should be considered, however, secondary glazing can be a cheaper way of insulating your windows.
Condensation is less likely to build up on warmer surfaces, so insulating the walls and roof is recommended. Insulation gaps, or cold bridges, can encourage condensation as warm damp air will concentrate and condense on this part of the home. If you have a well-insulated home but have certain walls or parts of your home that are not insulated, then there is every chance that you will find condensation gathered in those areas. Looking at areas that are well insulated versus areas that are not, could help you identify which areas to target by adding insulation measures.
If you have questions surrounding home insulation, please contact us through our online form here or call us on 0115 985 9057. We can assist you with advice on grants available and offer advice on insulation.
Penetrating damp
Penetrating damp is caused by water leaking through walls, ceilings, the roof, and floors. It is the result of structural issues in the building, which can stem from cracks, broken roof tiles, gutter problems, leaky pipes, and more. This means the damp can be exacerbated with lots of rain or during the winter if it snows.
You may notice penetrating damp if your paint is flaking off the walls, if you have cracked masonry, rotting wood panels, and/or a leaky pipe or guttering.
If you have rendering on your home, be aware that cracks in the render may allow water to seep in from the outside. It is important to note that the render material used, determines how much moisture is absorbed through the walls (i.e. concrete will not let moisture pass through, whereas a lime based plaster will).
To prevent penetrating damp, you must identify the root of the problem, with the solution most likely being an adjustment to the structure of the building. For example, you may need to clear and/or repair your gutters, replace roof tiles, or seal cracks in your rendering. The solution could be straightforward, or it could involve you consulting with a builder or damp specialist who can help best treat the problem.
‘Rising Damp’ by Kebabknight, 2018, from en.wikipedia.org.Rising damp
Rising damp is when water rises from the ground through the walls of your home. It can be recognised by a ‘tide mark’ on your walls or skirting board.
Modern buildings allow small amounts of water into the walls. However, this does not cause damage due to the presence of a damp-proof course or damp-proof membrane. A damp-proof course is a horizontal barrier, typically made of plastic or bitumen, which is installed in the walls to prevent moisture from rising through the structure. (CSE) Rising damp occurs when the damp-proof course is damaged or when the building does not have one installed.
If you live in an older home, you may have never had a damp-proof course installed. Alternatively, it could have been damaged during building work or the ground outside could have been raised (i.e. through a patio or decking), causing groundwater to seep in at a higher level.
Evidently, rising damp can be a complex problem. You may have a good idea of the cause, but it is best to consult a specialist who can advise you on the problem and how to fix it.
It is important to properly treat damp and mould as it can damage your home and can impact your health. It is much easier to get ahead of damp before it becomes a problem. If you are finding that your home has excess moisture, our tips can help you identify where the issue is coming from, or whether you need to seek help from a professional.
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