Window condensation

[diamond4u]

How can I prevent this? I seriously don't remember growing up with condensation on the windows.

With cold days now, every morning I am waking up to condensation on the windows, I've read it's the hot air touching the cold windows which is the result of condensation. I hate having to clean off the water every morning form all the windows, they are big bay windows.

Any helpful suggestions welcome!

Get a decent dehumidifier that will help.

Condensation is always worse the first week or so when the weather turns.

Don't dry washing inside if you can help it.

Get a dehumidifier and leave it running overnight, you will probably need one for each room that has a condensation problem.

If you have single-glazed windows, getting them replaced with triple-glazed ones will help.

If these ideas are too expensive the only other option is to reduce the temperature in your home so that there is no warm air to form condensation on the cold glass. Leaving the windows open in the bedroom and turning off the central heating will do the trick though will make it very unpleasant to live in. You have to decide whether keeping the temperature healthy is worth the effort of wiping down the windows.

Sleep with the windows open a crack. It won’t make much different to the temperature but will help either the inside moisture.

We have a dehumidifier, can't sleep in the room if it is on and it is an expensive quiet one. So we also have a small Karcher window vacuum thingy.

The windows get cleaned down every morning and the dehumidifier is turned on.

We tend to leave it running on the landing to keep humidity down and air the house every day! Our house is old, very old. Single glazed windows are all we can have... though we are working on that!

Yes so I've been researching dehumidifiers this morning! Then very quickly got confused when I saw option for humidifier.
So is it a dehumidifier that I need?

I never dry washing indoors, so there's definitely no moisture coming from clothes being dried.

We don't have the heating on all day, cold days, once in the early morning and then again either in the evening or in the night, it turns off itself after house is heated to what is needed.

I do also open all the windows in the morning after kids are in school and I've cleaned off the condensation, it's just the upstairs one that are open as am downstairs with baby so can't have window open in the room am in.

We have double glazed windows

Open windows 10 mins each day. Buy a karcher window vac, use it to remove moisture rather than towels. I do have a dehumidifier but they are not v energy efficient to leave running.

I have triple glazed windows and still get condensation in my bedroom. It's north-facing. It's the warm moisture breathed out overnight condensing on the cold windows that causes it AFAIK?

They aren't that expensive. 10p an hour on average, so 20p per usage at most, as they don't run on max all the time. Once a day, if that! Ours was a bit expensive Meaco 20l low energy one, but we have used it a lot in the last 2, almost 3 years, with no problems.

@diamond4u maybe start with a Karcher window vac. They come in at about £45 and are easy to use!

A dehumidifier is the easy option.

You can pretty much eliminate any damp problems with a piv unit.

Not too expensive or hard to install.

It will slowly pump in filtered air from the loft space and push out the stale damp air causing the condensation.

Do you drape wet washing inside your home?

How long does the bathroom extractor fan run?

Heat and ventilation the ultimate duo in the fight against condensation.

Oh this is timely!

I'm in a rental and it is humid/damp although there are no damp patches on the walls & it doesn't smell. After reading recommendations on MN I bought a Meaco dehumidifier (£170!) and was amazed & horrified in equal measure at the amount of water its extracting - the full 12 litres whist I'm out at work and still the reading doesn't drop below 53 (45 - 50 being the optimal % for house humidity).

Since then I bought 3 humidity monitors. The reading upstairs in both bedrooms doesn't drop below 65% "wet with a sad face" without the dehumidifier going constantly.

The kitchen reading shoots up to over 80% when simply cooking pasta even with the window open; the condensation literally runs down the glass splash backs. The lounge room monitor reads low 60's constantly.

Anyway, the "damp man" has just been round, after me complaining to the landlord. He's said its a combination of a lack of extraction & no clean air circulating down from the loft as the eaves have been too well boarded up and there is a non breathable membrane that lines the underside of the roof. He's recommending that a unit is placed in the loft to circulate a trickle of clean air down through the house, (the vent being in the ceiling on the landing & he's said its v quiet), the extractor in the bathroom is upgraded & one is also fitted in the kitchen.

Now whether the landlord agrees to this is another matter!
.

the only other option is to reduce the temperature in your home so that there is no warm air to form condensation on the cold glass. Leaving the windows open in the bedroom and turning off the central heating will do the trick

I found the exact opposite - illogical as it sounds.

In autumn when it's still mild enough to switch off the heating at night, I have condensation on the windows in the morning. As soon as the heating is left on permanently, no more.

The main reason I do have the heating is to dry the house to be honest. Laundry never dries inside the house, but we still have showers, breath.. and this country is horribly damp. All windows are opened fully for an hour in the morning, and most are left cranked opened most of the day.

reducing the temperature in your house will not reduce RH.

But ventilating it will.

@HCHQ

Oh this is timely!

I'm in a rental and it is humid/damp although there are no damp patches on the walls & it doesn't smell. After reading recommendations on MN I bought a Meaco dehumidifier (£170!) and was amazed & horrified in equal measure at the amount of water its extracting - the full 12 litres whist I'm out at work and still the reading doesn't drop below 53 (45 - 50 being the optimal % for house humidity).

Since then I bought 3 humidity monitors. The reading upstairs in both bedrooms doesn't drop below 65% "wet with a sad face" without the dehumidifier going constantly.

The kitchen reading shoots up to over 80% when simply cooking pasta even with the window open; the condensation literally runs down the glass splash backs. The lounge room monitor reads low 60's constantly.

Anyway, the "damp man" has just been round, after me complaining to the landlord. He's said its a combination of a lack of extraction & no clean air circulating down from the loft as the eaves have been too well boarded up and there is a non breathable membrane that lines the underside of the roof. He's recommending that a unit is placed in the loft to circulate a trickle of clean air down through the house, (the vent being in the ceiling on the landing & he's said its v quiet), the extractor in the bathroom is upgraded & one is also fitted in the kitchen.

Now whether the landlord agrees to this is another matter!
.

You say the loft has insufficient ventilation due to being felted and having the eaves blocked.

The more usual remedies, with £0 running costs, is to ventilate the loft better, typically by drawing back insulation stuffed into the eaves, sometimes drilling through the soffits or gables, sometimes by slipping tubes into the overlaps in the roofing felt to open un a ventilation gap.

Perhaps you "damp man" is in the business of selling PIV.

@missisboote I've noticed condensation is always worst in the autumn when it first starts getting cold too. Much worst than midwinter, despite not being as cold. Any idea why?!

p.s.

Air does not naturally "filter down" into the house from the loft. Convection means that it flows upwards. If you open the front door and the loft hatch, you are pretty sure to feel it rushing up (this is also a good way to cool the house on hot sunny days, or to clear the smell of frying garlic)

I don't get condensation on the windows at the back of the house, the bathroom window doesn't get it which is at the back, I don't know if it's because the back of my house is south facing. It's just all the windows at the front.

When we had central heating installed, we were told heaters get placed under windows to stop condensation, clearly not in my case.

Will have a look at karcher window vac and dehumidifier

I have to crack the windows open at night, it seems to help a little. I’m severely allergic to mould so I have to be very careful. The condensation is actually worse now I have brand new windows!

@Goldyyy - something about the damp coming out of the brickwork/house after a warm summer/autumn? Maybe?

That makes sense!

[quote MissisBoote]@Goldyyy - something about the damp coming out of the brickwork/house after a warm summer/autumn? Maybe?[/quote]
yes, strangely, UK houses (in good condition) have lower humidity in winter than in summer, due to the central heating drying out the fabric. So you will get a few days of higher humidity when the heat of the radiators evaporates out the walls and plaster. This is also why modern houses don't usually get woodworm, because the wood is too dry for them.

And because the outside air contains less moisture, being colder, its RH drops when you ventilate it into the house and warm it to room temperature.

@PigletJohn

reducing the temperature in your house will not reduce RH.

But ventilating it will.

Warm air holds more water than cold air. So when warm air is cooled by cold window, it drops water - condensation.

The air outside is cold so has less water in it, so ventilation is replacing damp air by dryer air.

Dehumidifier removes water and makes your warm air dryer.

Reducing temperature indoors means indoor air can't hold as much water as it could when it was warmer, so should also reduce condensation.

We have the same problem - North facing, upstairs double glazed bedroom windows. We never have damp washing hanging around so that’s not the cause. I too think it’s due to breathing during the night. Every morning I have to wipe the windows down with a towel. The blinds are ruined but what’s the point of replacing them?
We have a dehumidifier which removes plenty of water during the day, but it’s too noisy for overnight.
I’m searching for an answer too.