The Weather Inside: A Survivor’s Guide to November’s Window Fog

As I write this on 12 November 2026, my kitchen window is doing its annual impression of a car windscreen at a motorway services. The kettle has just boiled, the back door has been shut since breakfast, and the glass is wearing a fine coat of indoor weather. It is officially condensation season.

You can tell it is November not by the calendar but by the small rituals. The sleeve of a jumper dragged across the bathroom mirror. The squeegee that lives behind the washing-up liquid. The sudden, serious conversations about dehumidifiers in the school playground. Every British home becomes a tiny meteorological experiment, and we are all amateur forecasters.

The first fog of the season

My first fog arrives quietly. One morning the bedroom window is clear; the next it is beaded with water, and the sill has that faintly condemned look. By the end of the week, the spare room smells like a swimming pool changing room and the word ‘damp’ has entered the group chat.

Condensation is not mysterious. Warm, moist air meets a cold surface, and the water vapour gives up. In a British November, the cold surface is usually a window, a wall, or the back of a wardrobe. The moisture comes from us: showers, kettles, cooking, breathing, and the endless laundering of gym kits and tea towels. A family of four can add litres of water vapour to the air every day without trying. Add closed windows and a heating schedule that would make a lizard weep, and you have the ingredients for indoor fog.

The window vacuum question

There is a quiet social hierarchy to window condensation. At the bottom are the sleeve-wipers, who smear the glass and call it character. Above them are the microfibre pragmatists, who keep a cloth on the sill and wring it out with a sigh. At the top sits the window-vacuum aristocracy: people who own a handheld suction gadget, keep it charged, and will mention it at least twice before Bonfire Night.

I am not here to mock the window vacuum. If you have the budget and the cupboard space, a decent one hoovers up the water before it runs down onto the paintwork. But a clean microfibre cloth and a squeegee will do most of the job. The key is to wipe daily rather than wait for the window to stage a full re-enactment of the Titanic. Wring the cloth out properly, rinse it, and do not leave it sitting damp on the sill. That is just condensation with a host.

Laundry, the final boss

If windows are the visible symptom, laundry is the engine. Drying clothes indoors in November is a national sport with no winners. Draped over radiators, they release moisture slowly into the room while blocking the heat. Hung in a cold spare room with the door shut, they create a rainforest with a faint smell of fabric softener.

The practical answer is not glamorous. Spin clothes as dry as the fabric can take. Hang them with space between each item so air can move. Put the airer in the smallest room you can spare, close the door, and run a dehumidifier or a heated airer. If you are using a dehumidifier, empty the tank before it overflows, and choose the right type: desiccant models tend to work better in cool rooms, while compressor models prefer warmer spaces. A cheap humidity meter can tell you whether you are winning or just making soup.

And please, give the bath extractor fan a chance. Ten minutes after a shower is not a luxury; it is basic crowd control for water vapour.

The ten-minute airing

Here is the counterintuitive bit. When the windows are fogged, our instinct is to shut everything and turn up the heating. That often makes it worse. A short, sharp airing works better than a lukewarm fug. Open a couple of windows wide for around ten minutes, ideally on opposite sides of the house to create a cross-breeze. Yes, the room will go cold. Yes, you will complain. Then close the windows and let the heating recover. You have exchanged damp indoor air for drier outdoor air, and the windows will thank you.

I do this first thing, before the heating kicks in, and again after cooking. It has become as automatic as putting the bins out. The trick is to make it a habit rather than a project.

Mould patrol

Mould is the part of condensation season that stops being funny. It likes cold corners, poor airflow and damp soft furnishings. Behind the sofa is a classic. So is the back of a wardrobe, the window reveal, and the bit of wall where the bed is pushed too close. Once a week, I do a quick patrol with a torch: move a cushion, look behind the sofa, check the skirting in the spare room. Furniture wants a small gap from the wall so air can move.

If you find mould, clean it properly with a suitable mould cleaner and deal with the moisture source. Painting over it is not a fix; it is a cover-up. If it keeps returning, it is worth asking whether the room needs better ventilation, a dehumidifier, or a professional look. That is less fun than buying a new cushion, but it is cheaper than a new wall.

A small toolkit

My November kit is not fancy: a pack of microfibre cloths, a squeegee, a cheap humidity meter, a dehumidifier that lives in the spare room, and a window vacuum I borrowed once and have been polite about ever since. The best investment is the ten-minute airing, because it costs nothing and works.

At Dnays, we are not engineers or damp specialists. We are just people who have watched a window cry and decided to do something about it. Condensation season is a nuisance, but it is also a very British kind of weather: personal, indoors, and slightly ridiculous. Wipe the glass, air the room, and keep an eye on the corner behind the sofa. The fog will lift eventually. Probably around April.