Why are my bedroom windows soaking wet every morning? Experts explain the reason and why ignoring it could cause damage

Over the past week, there's been a real shift in temperature, and if, like me, you are waking up to windows that are soaking wet, it's a sign that condensation season is upon us.

I test some of the best dehumidifiers, and I've started blasting mine already to help clear my steamy single-glazed windows. According to experts, that sudden increase in condensation at this time of year doesn't necessarily mean there is anything wrong with your windows. In most cases, it's the result of autumn's colder nights colliding with the moisture we naturally produce inside our homes.

'Bedroom windows are often one of the first places you'll notice condensation in autumn because they're exposed to the colder overnight temperatures while the room is still picking up moisture as you sleep,' explains Allan Reid, uPVC specialist and founder of Art Windows and Doors.

So I asked three experts to delve into what you can do to stop condensation forming on windows.

Why your windows become wet in the morning

Condensation forms when warm, moisture-laden air comes into contact with the cold surface. As temperatures fall overnight, your window glass becomes one of the coldest surfaces in your bedroom, making it an obvious place for excess moisture to gather.

'As nights become colder, the temperature of the window glass falls,' explains Chris Michael, Meaco's co-founder and air treatment expert. 'Moisture in the room condenses on this colder surface, so windows can suddenly become wet even without an increase in indoor moisture.'

In autumn, the problem gets even worse when windows stay closed for longer, the heating goes back on, we're drying our laundry indoors again and sleeping in your bedroom adds to the moisture in the air.

'We release moisture in our breath and skin throughout the night, while the window glass cools,' Chris explains. 'Over several hours, this can leave water running down the glass and collecting on the sill by morning.'

Chris estimates that one person can produce around half a pint of moisture overnight! So in a bedroom shared by two people, with the windows and door firmly closed, you can see why humidity can quickly increase.

Pamela Petty, Director at Ebac, agrees that shutting the door to a bedroom overnight can make the problem so much worse. She recommends keeping the door open or even slightly ajar, which can improve air circulation and stop moisture from becoming concentrated in one room.

What you can do about condensation forming on your windows

The first thing I'd do is remove the visible water first thing because leaving it sitting on the glass, seals and sill creates damp conditions that mould thrives in.

'If you're waking up with soaking windows, don't just wipe the glass and forget about it,' warns Allan. 'Give the room a proper airing in the morning and make sure the windowsill and frame are completely dry, particularly around the corners where water can sit unnoticed.'

Opening your curtains and blinds fully in the morning is really important too. Thick curtains and blinds can create a pocket of cold, stagnant air against the window, so Allan recommends keeping them slightly away from the glass overnight.

Pamela similarly suggests leaving particularly heavy or full-length curtains open by a few centimetres overnight to encourage airflow around the glass.

Your window's trickle vents are also worth checking, as 'they can be easy to forget about, but they're there to provide a steady flow of air, without having to leave the window wide open,' explains Allan.

He also suggests checking that they're open and haven't been blocked with dust or paint.

The products I use to tackle wet windows

These are just a few of the products I always use in autumn that can make a huge difference. Some tackle the water you're seeing, and others help to prevent it from appearing in the first place.

When you should worry about condensation

According to the experts, occasional condensation on a particularly cold morning is common, but windows that are soaking wet every single day deserve more attention.

'Condensation on windows is a visible sign of moisture that may also be affecting walls, furnishings and areas you cannot see, such as behind furniture and inside wardrobes,' warns Chris.

So relying on wiping the windows each morning probably isn't going to cut it. Check behind furniture, around window seals and in the corners of the room for mould, damp patches or musty smells.

If you're running a dehumidifier, Chris recommends aiming for around 50-55% relative humidity. A model with a built-in humidistat can monitor this for you, switching on when humidity rises and stopping once its target is reached.

However, a dehumidifier shouldn't be used to disguise an underlying building problem. If condensation is persistent alongside damp patches, recurring mould or a musty smell, Chris recommends investigating other potential causes, including leaking pipes, blocked gutters or gaps around windows.

So there you have it! Don't panic if your windows have suddenly started dripping every morning, but don't ignore them either. A window vac can deal with the immediate puddles, and choosing a good dehumidifier can help you tackle the excess moisture at the source.

And if you combine these with a few small changes to your daily routine, that should all help to minimise all that moisture!