Eight ways to reduce condensation in your home | Home improvements

Tackle the sources

Condensation on windows happens when the glass is cold enough for water to condense. Upgrading to the most efficient triple-glazing can help but can cost thousands. Keeping the room temperature higher can also help by stopping the inside glass panes from getting so cold. Neither solution treats the underlying cause, however.

The bathroom and the kitchen are the two biggest sources of the moisture that creates condensation in most homes. By keeping the bathroom door closed and venting humid air using an extractor fan or by opening the window for at least 15 minutes after showering you can stop it spreading to the rest of your house. In the kitchen, using a cooker hood that extracts to the outside and opening a window while cooking helps keep moisture at bay and vents any air pollution it might create.

Dry laundry outside

Drying clothes you have washed outside helps prevent moisture buildup in your home even if it’s cold outdoors. If you must hang clothes indoors, do so next to an open window to help dispel some of the moist air and speed up drying.

Alternatively, you can use a dehumidifier to dry the clothes and trap the moisture they contain. Some have dedicated laundry modes but all of them work best in confined spaces, so close the door to the drying room, and cost on average about 7p an hour to run. Tumble dryers are faster and trap or vent moisture outside but cost quite a lot to use. Modern, energy-efficient heat pump dryers cost an average £51 a year to run, according to data from Which?, but the older technology condensing or vented dryers cost more at an average of £130 or £141 respectively.

Dry it off

If you can’t avoid condensation, thoroughly drying it off every morning can help reduce the overall moisture in your home in combination with ventilation or other means.

Once you have wiped away the moisture, ensure you remove any wet tissue from your home, don’t just put it in the bin for it to dry back into your home. Hang any wet towel or cloth outside or use toilet paper and flush it down the toilet.

Alternatively, use a window vacuum to suck the water off the surface into a container so you can tip it down the drain. They can be used on most glass and hard surfaces, including bathroom mirrors, shower screens and tiles, and cost from about £30.

Try Stosslüften

It seems counterintuitive to open the windows in the depths of winter but cold air can’t hold as much moisture as the warmer indoor air. There are limits, so use your common sense if it’s foggy or bucketing it down.

Cracking a small window open such as a fanlight will help, but if you want to be more proactive you can follow the German custom of Stosslüften or “impact” ventilation. Throw open all your windows for five or so minutes in the morning and evening to create a through draught, which will quickly vent out all the stale and damp indoor air and replace it with fresh outside air. The theory is only the air is cooled, not the walls or other surfaces, so it quickly heats up again once you shut the windows.

Open trickle vents

The little slots in the top of modern window frames called trickle vents are a way of allowing a small amount of fresh air in and stale, damp air out without having to leave the window open all the time.

They work best when left open all the time but can be shut when it’s particularly cold or blowing a gale to stop draughts from making a home too cold.

Use moisture absorbers

These are a relatively cheap way of passively removing moisture from the air, costing from about £8 at DIY shops. They work by using desiccants to attract and trap water so you can remove it from a space

One type uses a block or crystals of calcium chloride that absorb water and drip into a tank that you empty. You can buy refills of the crystals to reuse the tank.

Another type comes as a fabric bag of silicon dioxide beads that absorb water and release it when heated, usually via a microwave oven as part of the recharging process.

Neither can handle lots of moisture but are useful for smaller spaces such as smaller rooms, cupboards, vehicles or caravans.

Buy a dehumidifier

One of the most effective solutions to excess moisture in the home is an electric dehumidifier. They come in two types – both use a fan to draw in damp air and trap its moisture before blowing drier air into your home. Prices start at about £100 and they simply plug into a wall socket – no DIY or construction is required. Most have sensors that automatically maintain a set humidity but it’s important to get the right size of machine for your home.

Condensing dehumidifiers are the most common in the UK and work like a fridge, using a compressor to create a cold radiator or surface that condenses the water that then drips down into a bucket. The air is then reheated and sent back into the room. They are typically the most energy efficient but work better at higher temperatures, so are less effective in very cold homes.

Desiccant dehumidifiers draw air through a rotating wheel covered in moisture-absorbing material. The water is trapped on one side of the machine then released for disposal into a tank when heated on the other side. Their action is not temperature dependent, so they work effectively in cold homes, but they consume more electricity.

Ventilate

Positive ventilation systems are the opposite of extractor fans and bring in fresh air from the outside to push stale and damp indoor air out, usually through small leaks or vents. There are a number of types but most require professional installation including wiring and the fitting of ducting and vents.

Positive input ventilation (PIV) is the simplest form, consisting of a fan fitted in a loft space or on an external wall that runs all the time and slowly pushes air through a single vent in the ceiling or wall. PIV units cost from about £300 and require the least work to your home. Most have built-in air filters. Some have electric heaters for the incoming air, though using them increases energy usage.

Mechanical ventilation heat recovery (MVHR) is a more sophisticated and energy-efficient version. It combines extractor fans with PIV, typically drawing out the hot and moist air from bathrooms, kitchens or similar, using it to heat fresh air from the outside that is then pumped into living areas. MVHR uses multiple vents and ducting, so can be difficult to retrofit and costs thousands to install, but it keeps energy consumption to a minimum and ensures the air coming into your home is not cold.