How to save energy and stay warm in winter

Most heating energy escapes through gaps, cold walls, uninsulated pipes and poor habits — not through using heating itself. Fix the leaks first, then decide when and where to run the heat.

Heat the person, then the room

The cheapest unit of heat is the one you keep inside your clothing. Before reaching for the thermostat, add a layer — a warm jumper, thick socks, or a fleece blanket on the sofa can let you sit comfortably at a noticeably lower room temperature.

• Wear thermal base layers under ordinary clothes on very cold days — they trap a thin layer of warm air next to your skin.
• Keep feet warm. Cold feet make the whole body feel cold. Slippers or thick wool socks make a real difference.
• Use a throw or blanket if you're sitting still — sedentary bodies generate less heat than moving ones.
• Warm bedding over a warmer bedroom. A good duvet (with appropriate tog rating for the season), a hot-water bottle, or an electric blanket used to pre-warm the bed all let you sleep comfortably with the heating off or turned right down overnight.
• Close doors between rooms. Concentrating warmth in the room you're actually using means you don't need to heat the whole house to the same level.
• Put a rug on bare floors. Hard floors feel cold underfoot and let draughts travel across the room. A rug doesn't insulate the floor significantly, but it stops the cold-feet sensation and makes the space feel warmer instantly.

Thermostat settings and timers

How you control your heating matters almost as much as how well your home is insulated.

• Set a timer. Programme your heating to come on shortly before you get up and to go off shortly before you go to bed or leave the house. Heating an empty or sleeping home wastes money. What counts as "shortly" depends on how well your home holds heat.
• Try lowering the thermostat by 1°C. Dropping your target temperature even modestly — say from 21°C to 20°C (70°F to 68°F) — reduces heating energy meaningfully. Put on a layer first and see if you notice the difference in comfort.
• Use thermostatic radiator valves (TRVs). If you have them, turn down or off radiators in rooms that are rarely used. Keep them on a low setting rather than fully off in very cold spells, to prevent damp.
• Don't turn the heating completely off if you're away for a few days in cold weather. A frost-protection setting (around 7–10°C / 45–50°F) prevents frozen pipes without spending much energy.
• Zoned or smart thermostats let you set different temperatures for different times and sometimes different rooms, which can help if your household has varying schedules.

Draught-proofing, curtains and door snakes

Draughts — cold air sneaking in through gaps — make rooms feel colder than the thermometer shows, so you turn up the heat to compensate. Stopping the draughts is often the single most cost-effective thing you can do.

• Check the obvious gaps first: around external doors (the frame, letterbox and keyhole), window frames, gaps around pipes that enter through walls, and the loft hatch.
• Self-adhesive foam weatherstrip around door and window frames is cheap and takes minutes to fit. It compresses to seal when the door closes.
• A door snake or draught excluder at the bottom of a draughty door is one of the lowest-cost fixes available. You can buy one or stuff an old pair of tights with fabric scraps.
• Heavy curtains (or thermal-lined curtains) over windows hold a surprising amount of heat in. Open them wide on sunny days to let winter sun warm the room; close them at dusk to trap that warmth.
• Floorboard gaps can let cold air rise from below. A flexible sealant, draught-excluding tape or a large rug covers them easily.
• Chimneys that are no longer used are a major source of cold air. A chimney balloon or flue draught excluder blocks the column of cold air that descends without blocking gases from any working flue.

Radiators: bleeding, clearing and reflectors

A poorly maintained radiator can use as much energy as a well-maintained one and still heat the room less effectively. A few simple checks pay back quickly.

• Bleed radiators that have cold patches at the top. Air gets trapped in the system and stops hot water reaching the full surface. Bleeding (with a bleed key, a small tool sold in hardware shops) lets that air escape and water fill the space. Do it at the start of the heating season.
• Don't block radiators. Furniture pushed against a radiator or curtains that hang over it trap heat behind them rather than warming the room. Leave a gap of at least 30 cm in front, and stop curtains at the windowsill rather than falling over the radiator.
• Radiator reflector panels fit behind radiators on external walls — they reflect heat that would otherwise soak into the cold wall back into the room. They're inexpensive and easy to fit. Most useful on poorly insulated external walls.
• Keep radiator surfaces dust-free. Dust reduces efficiency; a quick wipe along the fins at the start of the season is worthwhile.
• A boiler service (where applicable) every year or two keeps the system running efficiently and catches problems before they become expensive. Check what's normal in your country.

Hot water in winter

Hot water demand rises in winter — longer, hotter showers, more washing-up. A few habits keep the costs from creeping up.

• Insulate your hot water cylinder with a jacket if it doesn't already have one — it's a low-cost fix that stops heat bleeding away when the water is sitting waiting to be used.
• Insulate the first metre or so of hot water pipes from the cylinder — they lose heat fast and cool down between uses.
• Set the hot water temperature to a safe but not excessive level. For most storage cylinders this is around 60°C (140°F) to prevent bacterial growth, but check the guidance for your system type.
• Take slightly shorter showers — it's harder to resist a long hot shower in winter, but even a minute or two off makes a noticeable difference over the season.
• Fix dripping hot taps. A dripping hot tap wastes water and energy all day, every day.

Managing condensation and damp

Condensation happens when warm, moist air meets a cold surface — windows, external walls, the inside of cupboards on outside walls. In winter it's more common because surfaces are colder and we ventilate less. Left untreated it leads to mould, which causes health problems and damages the building.

• Ventilate when you produce moisture. Run the extractor fan or open a window when cooking, showering or bathing. A few minutes of ventilation while the steam is being produced prevents a lot of condensation.
• Don't dry clothes on radiators in rooms without ventilation. Wet laundry releases a large amount of water vapour into the air. If you must dry indoors, open a window slightly or use a dehumidifier. A vented or condenser tumble dryer removes the moisture from the house entirely.
• Keep a background heat in very cold rooms. A completely unheated room in winter can become cold enough that even ordinary air moisture condenses on every surface. A low TRV setting helps.
• Wipe down condensation on windows and sills to stop it soaking into paintwork, frames or walls.
• Leave small gaps behind furniture on outside walls, and inside cold cupboards, to let air circulate and prevent mould from developing in hidden spots.

Check on elderly and vulnerable neighbours

Cold homes are a serious health hazard, particularly for older people, very young children, and anyone with a respiratory or cardiovascular condition. During cold spells, a brief check on an elderly or vulnerable neighbour can genuinely save lives. Many countries have cold-weather alert systems, fuel poverty support schemes and emergency heating assistance — if you or a neighbour are struggling to afford adequate heating, look for local government or charity support.

Winter warmth checklist

• Add a layer before reaching for the thermostat.
• Set a heating timer so you heat only when home and awake.
• Lower the thermostat by 1°C and see if you notice the difference.
• Fit draught excluders around one draughty door this week.
• Close curtains at dusk to trap warmth in the room.
• Bleed any radiators with cold spots at the top.
• Move furniture away from radiators and let curtains stop at the sill.
• Consider fitting reflector panels behind radiators on external walls.
• Ventilate when cooking or showering to prevent condensation.
• Insulate the hot water cylinder and the first run of hot pipes.
• Check that your CO detector is working if you have gas or solid-fuel appliances.
• Check in on elderly or vulnerable neighbours during cold spells.