Condensation on Windows
Condensation on Windows is one of the most common places we see condensation in properties and so we have written this guide on how to stop condensation on windows, with 20 different solutions. Clearly the more of the things on this list you can do, the better chances you have of lowering condensation in your home. You’ll likely always have some condensation but you can reduce it, and importantly, help to remove / reduce it once you have it.
Although this is a guide to condensation on windows, it can also be relevant to condensation problems on other surfaces in your home:
- Condensation on pipes (especially cold ones)
- Condensation in bathrooms
- Condensation and damp on walls and ceilings
- Condensation in your loft – which we have a specific guide for
- Condensation on tiles etc
We’ve written an article about anti condensation paint and, as we say in that, you can’t really use something like that on glass windows (it has limitations too) so other things need to be considered and, luckily we have a lot of suggestions below!
What Causes Condensation on Windows?
Condensation occurs usually when relatively warm, moist (humid) air comes into contact into a surface which is at or below dew point for that air. So what does that mean?
We discuss this in our guide to relative humidity but, put more simply – there is moisture in the air, when that air reaches a cold surface (such as a window) it condenses, changing from vapour to moisture / water. Think of vapour a bit like steam coming from your kettle, it dissipates into the air. The amount of water vapour / humidity in houses will depend on a number of factors (more on that later).
When looking to stop condensation on windows you are usually trying to do one of 3 things:
- Reduce the humidity in your house
- Prevent cold surfaces on which condensation will collect
- Help the dissipation of moisture from condensation (evaporation!)
- Or, ideally, all of the above
People trying to stop condensation on windows is a more common problem in the colder months of the year as you might expect, for a number of reasons related to our tips below.
There are other examples of where condensation occurs which, with the information from above, will give good examples of how the condensation process occurs. Such as:
- Condensation on the outside of a cold glass with ice on it
- Condensation on spectacles when you go from outside to indoors
- Dew collecting on grass overnights
- A bathroom mirror fogging over when you have a bath or shower
- Condensation on a toilet cistern, matching up with where the cold water is
- When you breath out on a cold winters day, causing steam
Should I worry about condensation on my windows?
It is not unusual to see condensation on windows, especially in colder months and especially in bathrooms and kitchens. However, excessive or prolonged condensation can cause:
- Problems with mould on walls or ceiling, which can cause health problems. In fact our guide on how to stop mould on walls has similarities with the list we are going to go through below on tips to stop condensation on windows. Moisture from condensation provides the moisture that mould requires. Think of it like watering plant seeds to get them to grow. There is more on this in our guide to what causes mould.
- Problems with damp or rot, especially if left for a long time. This is especially the case with wooden surfaces or porous materials. Managing to stop condensation on windows could help this too.
- Related to the previous points, you can get odour problems with mould and damp
- Particularly bad condensation can cause surfaces to become slippery with is a health and safety risk in your home, especially for the vulnerable.
How to Stop Condensation on Windows – 20 ways
Here is our list of 20 tips to stop condensation on windows:
- Check you do not have a water leak – of course you would expect that from a website about water leaks! However, if you are getting unexpected or unusually high levels of condensation on your windows, walls etc, especially at unusual times of the year – it is possible you have a water leak. We mentioned at number 5 on our list of signs of a water leak. When we go to properties who have had a water leak, it is not unusual to see high humidity and condensation. This is especially the case with central heating or boiler leaks as the water will often be warmer.
- Have good extractor fans in your bathroom – extractor fans are common in bathrooms. They are there to remove the moist air out of your property to help tackle excess moisture in your house coming from the steam from baths and showers. Notice also that we say good extractor fans. That is because a poor extractor fan or an old one may not be up to capability. We have ways of measuring airflow through extractor fans, most commonly we rate them for cubic feet or cubic metres per minute. They really help to reduce condensation in bathrooms.
- Have good extractor fans in your kitchen – this is especially the case above where you do your cooking because the steam from pans is then extracted at source meaning it does not go into your home. On this, two other things to remember – fans that extract externally are better than ones which recirculate air through a filter.
- Keep lids on pans on your hob – wherever possible you should do this because otherwise, the steam from the pan boiling or simmering will go into the air, especially if you are cooking for a long time. You will notice that the water level in a pan will drop the longer it is cooking, all that water goes into the air. Keeping a lid on pans etc will contain the moisture / steam and stop condensation on windows in your kitchen.
- Keep your extractor fans clear of dust / blockages – we mentioned earlier about the value of extractor fans in controlling moisture in the air. In order to keep them running optimally, try to keep airflow to them clear avoiding blockages, including dust. Also, wherever possible, and if they have them, replace filters on extractor fans for cooker hoods etc. This will help with their efficiency and effectiveness in helping to stop condensation on windows and other surfaces.
- Keep bathroom and kitchen doors closed – a bit like the previous point, if you can keep doors closed on rooms which have a lot of steam from hot water it will help to contain the moisture and allow the extractor fan to do its job taking the moisture out of your house. Related to that…
- Think about window ventilation (including trickle vents) – if you can keep your windows open for a time, or even open on ‘crack’ (where it is locked but with a gap to the open air), including the use of trickle vents, it will help control moisture in the air which will form condensation. It can also help with the evaporation of condensation if and when it occurs. Clearly this is more difficult in colder months, especially winter, but can make a difference to stop condensation on windows. In some properties, high level air bricks can help with ventilation and are sometimes found in bathrooms.
- Double or triple glazing – most modern houses have double or triple glazing which not only helps to keep houses warmer through improved insulation values, but the side effect of that is that the interior pane of glass is not as cold as you would get on a single paned window. So remembering our point earlier about water condensing on cold surfaces, this will help reduce that.
- Curtains and blinds – on the subject of windows, wherever possible, keeping curtains and blinds open helps to keep airflow improved around windows which will help to prevent condensation and improve evaporation. Also, keeping blinds and curtains closed can stop warm air from radiators etc helping to keep the windows warm and dry. Very much on that point…
- Placement of radiators and heaters – it is common for radiators to be placed under windows. Traditionally, this would be the coldest place within a room (especially with single paned windows) so having radiators placed under or near windows can help to counteract that and warm the air which may be coming in from drafty air. The other benefit when looking at how to stop condensation on windows is that the radiators can (a) help keep the window warmer making water less likely to condense and (b) help any condensation to evaporate off the windows
- Be wary of moisture from plants – clearly plants in a property need to be watered to help them grow and stay alive. Plants can add to humidity in homes. Watering provides moisture to the plant will either evaporate from the soil or from the plant leaves over time. Basically, most of the water you add will ultimately go into the air in your house. So be aware that having plants can add to the problem when looking to stop condensation on windows.
- Avoid drying clothes from laundry indoors – people often put clothes on clothes horses, often near radiators or fires etc, to help dry their clothes after washing. Again, as they dry they lose moisture which will go into the air and potentially condense on cold surfaces such as windows. So if you are looking to stop condensation on windows, dry your washing outdoors whenever weather permits or, when you cannot, use a vented of condenser tumble dryer to contain the moisture in the air. Very much on that point…
- Laundry room vents and ventilation – for the reasons just stated, drying clothes involves removing the moisture from them. When clothes are dried using a vented dryer, the vent removes the humid / steamy air out of the dryer so always vent tumble dryers outside where possible, do not let them vent into the house as this will not help when trying to stop condensation on windows. Clearly condenser dryers collect the water to be drained into a sink or wherever and are much less of an issue.
- Insulating your home – the better you can keep your home insulated, the warmer it will stay. This can include loft insulation, cavity wall insulation etc (and double glazing as we said earlier). The warmer your house the more likely you are to have cold surfaces, including windows, to help reduce condensation collecting on. A warm and insulated house will help to stop condensation on windows.
- Mop up when condensation occurs – if you do have a problem with condensation on the inside of your windows, try to mop or wipe it up whilst you are looing at ways to stop condensation on windows in the longer. You can also get window vacs (such as the karcher window vac) which are designed to remove moisture from windows, either condensation or after cleaning them. Look to other things on this list for longer term solutions of how to stop condensation on windows.
- Keep good airflow around windows – this is related to other points on this list around window ventilation, extractor fan ventilation and curtains and blinds but, in general, condensation is more likely to occur in poorly ventilated rooms. So try to keep good airflow. This might sound like it contradicts number 6 on this list (about keeping doors closed) but that refers more to when you are actually having a shower or cooking. A PIV unit can help with ventilation in a home too.
- Fans and air movers – very much related to the previous point, fans can help stop condensation from occurring in the first place or help condensation to evaporate if it does occur. Clearly, do not use fans directly in bathrooms or kitchens (unless they are designed to and professionally fitted – like extractor fans) but they can help general air movement around a house. That can also help spread heat to keep a house warm too, helping to reduce heat and cold variances from room to room.
- Dehumidifiers – if you do have a problem and are looking to stop condensation on windows, walls or ceilings etc, dehumidifiers can help remove moisture from the air and reduce relative humidity. Clearly, with less moisture in the air, there will likely be less or no condensation. Again, like some other things on this list, they can help with condensation but look to other areas to prevent it in the first place. You can find out more about dehumidifiers on our page about water damage restoration.
- HVAC systems – HVAC (which stands for Heating Ventilation and Air Conditioning) systems can help to control moisture in a property which can help to stop condensation on windows. They can also clearly help with heating surfaces and providing air circulation an ventilation too which are all factors on this list aimed at looking to stop condensation on windows. They are not cheap but they can be effective.
- Control other moisture sources – we have already talked on this list about moisture from cooking, washing, baths and showers etc, but you also need to look at other potential moisture sources. This will vary from house to house but you might have a problem with rising damp (one of the main types of damp) which can bring unwanted moisture or even something like a fish tank. These are sometimes heated too which can add to the problem. Be aware of things bringing moisture into your home.
So that is our list of things to stop condensation on windows, we hope you found it useful. Remember, as we usually say with lists such as this, the more things you can do on the list, the more liklely you are to stop condensation on windows.
Bonus tip to stop condensation on windows – clearly something that you might not be able to control but the sheer number of people in a home might contribute to higher moisture / humidity. Not only is this from extra people cooking, showering etc but also breathing moisture out with their breath. Bedrooms that have a lot of people sleeping in them will likely have higher levels of condensation. These things together are another reason for good ventilation as it helps with air quality and can help reduce spread of viruses from one person to another.
Bonus tip 2 – you can help to stop condensation whilst having a bath by 45% which we tested with amazing results. Remember that baths can contribute a lot to condensation.
We hope you found our guide on how to stop condensation on windows useful. If you have a problem with condensation in your property, or think you might have a water leak, get in touch with us today.
We did a test to look at bath vs shower condensation, the results were interesting indeed and can give some other tips to stop condensation on windows in your bathroom.