How to Reduce Heating Bills in Winter – Practical Steps That Actually Work

Heating and hot water together account for over half of the average UK household energy bill – a proportion that makes them the single biggest lever available when trying to reduce what you spend each year. The figure is higher for older, poorly insulated properties. That concentration means small changes to how you heat your home have an outsized effect on your total bill. The most effective measures are not particularly expensive or technical. Some cost nothing at all. The challenge is knowing which changes actually make a difference and which are too marginal to bother with.

This guide works through every practical measure in order of impact, starting with the adjustments that can be made this week at no cost and working through to the investments that pay back within a year or two. Everything covered here produces a genuine, measurable reduction in heating costs in a real UK home. The fringe measures – the ones that take effort and produce savings too small to notice – are left out.

Thermostat settings and temperature zoning

The room thermostat setting has more influence over your heating bill than almost any other single factor. For every 1 degree Celsius you reduce your thermostat setting, you reduce heating energy consumption by approximately 8 to 10 percent. Most UK homes are heated to 20 or 21 degrees. Reducing to 19 degrees is barely perceptible in comfort terms when you are dressed appropriately, but the saving compounds over a full heating season.

The recommended temperature ranges from energy advisers are 18 to 21 degrees for living rooms and 16 to 18 degrees for bedrooms. Bedrooms do not need to be heated to the same level as living spaces – most people sleep better in a cooler room, and heating a bedroom to 20 degrees when it will be occupied by someone under a duvet is simply waste. Frost protection temperature when the house is unoccupied should be around 12 degrees, not full heating left running on a lower setting.

Temperature zoning is the practice of heating different parts of the house to different temperatures rather than heating everything to the same level. A hallway, a rarely used spare room, or a bathroom used only in the mornings does not need continuous heating to the same level as the living room. Thermostatic radiator valves fitted to individual radiators allow this fine-grained control. A house with a well-set main thermostat, properly adjusted TRVs and a good heating schedule will typically use significantly less gas than a house with the same insulation where everything runs at the same temperature.

Heating schedules and smart controls

A well-programmed heating schedule is worth more than most people realise. Many households heat their homes for far longer than necessary because the schedule was set once – often when they first moved in – and never reviewed. A badly set schedule keeps heating running through hours when nobody is home, heats bedrooms when everyone is watching television downstairs, and maintains full temperature through the early hours of the morning when everyone is asleep.

The correct principle is simple: heat the space when it is being used, to the temperature needed for what it is being used for, and no more. Full heating should come on in time for the house to reach temperature before people need it – not hours before. A modern condensing boiler and a well-insulated house will typically reach temperature within 20 to 30 minutes, so there is no need to run heating from 5am when the house is not occupied until 7am. Setting the heating to start at a slightly lower temperature 30 minutes earlier uses less gas than heating rapidly from cold in a short window. A two-zone system – upstairs and downstairs – allows living areas to be heated during the day while bedrooms stay cooler, then bedrooms to warm up in the evening before bed while downstairs drops back.

Smart thermostats take the programming one step further. Systems from the major manufacturers learn how long your home takes to heat up and adjust start times automatically to hit target temperature exactly when needed, rather than relying on a fixed schedule that may start too early. They detect when nobody is home and drop to frost protection automatically. They can be controlled remotely, which is useful when plans change and the house would otherwise heat to full temperature with nobody in it. For a household that does not already have a well-programmed schedule, the savings from a smart thermostat can be significant.

Boiler efficiency and hot water

Most UK homes are heated by a gas condensing boiler. Condensing boilers are significantly more efficient than older non-condensing models, but only when they are operating in condensing mode – and most are not. A condensing boiler enters condensing mode when the water returning to the boiler from the radiators is cool enough for water vapour in the flue gases to condense rather than escape. This condensation releases additional heat that would otherwise be wasted. For this to happen, the return water temperature needs to be below around 55 degrees Celsius.

The problem is that most boilers are set from the factory with a flow temperature of 70 to 80 degrees. At that temperature, the return water is too warm for condensing to occur, and the boiler runs as a non-condensing boiler despite being designed as one. Reducing the flow temperature to around 55 to 60 degrees allows the boiler to condense, improving its efficiency meaningfully. This single adjustment can reduce heating costs by around 8 percent according to Nesta’s analysis of the measure across UK homes. The correct setting is found on the boiler itself – usually labelled as central heating temperature or flow temperature – and the adjustment takes under a minute. A Gas Safe registered engineer can confirm the right setting for your specific boiler if you are not sure.

Domestic hot water is the second largest component of a gas bill after space heating, and reducing waste here adds meaningfully to what is saved on the heating side. If your home has a hot water cylinder, check whether it has an insulating jacket – an uninsulated cylinder loses heat continuously, effectively paying to heat water that cools before it is used. The cylinder thermostat should be set to 60 degrees, which is the temperature required to prevent legionella bacteria from surviving during the heating cycle. Setting it higher than 60 degrees means heating water to a temperature that must then be mixed with cold water before it is usable, which is straightforward waste. Foam pipe lagging on the hot water pipes running from the cylinder to taps and showers reduces heat loss between heating cycles and is inexpensive to fit.

Draught proofing

Draughts account for up to 20 percent of heat loss in older UK homes. The older the property and the worse its maintenance, the higher that figure is likely to be. The most significant sources of uncontrolled draughts in a typical UK home are gaps around doors and windows, letterboxes, keyholes, loft hatches, floorboards on ground floors, and unused chimney flues. Addressing all of them systematically is one of the highest-return investments available per pound spent on home energy.

The most impactful single measure is often the chimney. An open chimney flue acts as a permanent ventilation shaft, drawing warm air out of the room and cold air in through every other gap in the building fabric. A chimney that is not in regular use should be blocked when not in use with a chimney balloon or a purpose-made wool plug. These devices must be removed before lighting a fire – fitting a visible reminder inside the fireplace prevents this from being overlooked. Door draught excluding is straightforward: brush strips or compression seals around the door frame, and a draught excluder or threshold strip at the base of external doors, address the most common entry points. Windows with gaps between the frame and the casement benefit from self-adhesive foam or compression strip seals, with sash windows requiring specialist draught seals to deal with the sliding joint between the upper and lower sash.

Ground floor floorboards in older properties often have gaps between them that allow cold air to rise from the void beneath. Flexible sealant applied between the boards fills the gaps without restricting natural movement of the timber. Loft hatches are frequently uninsulated and draught-prone: adding insulation board to the top of the hatch and a compression seal around the frame is a small job with a reasonable payback given how much warm air escapes through an uninsulated hatch into an unheated loft space.

Radiator optimisation

Radiators that are not functioning correctly waste energy that has already been paid for. The two most common problems are airlocks and sludge, and both are straightforward to address.

Trapped air in a radiator prevents hot water from filling it fully, producing cold spots at the top while the lower section is warm. Bleeding the radiator releases the trapped air using a bleed key – the process takes two minutes per radiator and should be done at the start of each heating season. A radiator that is cold at the top and warm at the bottom needs bleeding. A radiator that is cold at the bottom and warm at the top has a different problem: sludge has accumulated at the base, blocking the flow of hot water through that part of the panel.

Sludge is the black, magnetite-rich deposit that accumulates at the base of radiators over years of use. It is the product of internal corrosion within the system and progressively reduces the heat output of affected radiators while making the boiler pump work harder to push water through the system. A magnetic filter fitted on the return pipe to the boiler catches magnetite particles before they can accumulate in radiators and is the most effective long-term prevention. On an older system without a magnetic filter where sludge has already built up, the options are a power flush by a heating engineer, which clears the system mechanically, or a chemical flush for less severe cases. Magnetic inhibitor added to the system water after either treatment slows the rate of future corrosion.

Radiator reflector panels fitted behind radiators on external walls redirect heat that would otherwise conduct through the wall back into the room. They are particularly effective in solid-wall properties where wall insulation is not practical. The installation is straightforward – the panel slides behind the radiator against the wall – and the cost is negligible relative to the ongoing improvement in heat output.

Windows, curtains and insulation

Single glazing loses heat far faster than a well-insulated wall. Secondary glazing fitted inside an existing single-glazed window is significantly cheaper than replacing the windows and provides most of the thermal benefit of double glazing. For properties in conservation areas where external alterations are restricted, secondary glazing is often the only permitted option and performs well when properly fitted. For homes that already have double glazing, the marginal gain from upgrading to triple glazing is small relative to the cost, and the money is almost always better spent on insulation or draught proofing first.

Curtains and thermal blinds are consistently underestimated as an energy-saving measure. A well-fitted heavy curtain closed at dusk traps a layer of still air between the curtain and the window, reducing heat loss through the glass significantly compared to an uncovered window overnight. The curtain must be long enough to reach the floor and must overlap the window frame on all sides to be effective – a curtain that stops at the sill allows warm room air to circulate freely behind it, defeating the purpose. Thermal-lined curtains outperform unlined curtains. Fitted roller blinds with a reflective backing add a further layer of insulation when closed.

Roughly 25 percent of a home’s heat is lost through an uninsulated roof. The recommended depth for loft insulation in a UK property is 270mm of mineral wool, as set out in Part L of the Building Regulations. Many older properties have insulation laid years ago that has settled, become compressed, or was installed to a lower depth than current recommendations. Topping up existing insulation to the recommended depth is typically a half-day DIY job – mineral wool rolls are available at any builders merchant and require no specialist equipment beyond safety glasses, gloves and a dust mask. The payback on loft insulation is among the fastest of any home improvement measure.

Around 33 percent of a home’s heat is lost through uninsulated walls. Cavity wall insulation, where appropriate, fills the air gap between the inner and outer leaf of a cavity wall with mineral wool or polystyrene beads. Cavity walls can be checked by an insulation installer – a property built after around 1920 with a brick external wall is likely to have a cavity. The installation is done from outside through small drilled holes and typically takes a morning. Solid wall properties require internal or external insulation, which is considerably more expensive and disruptive, but the heat-loss reduction is proportionally larger because solid walls conduct heat faster than cavity walls.

Government schemes and grants

Significant financial support is available for insulation and heating improvements in England, Wales and Scotland. The two main schemes currently operating are the Energy Company Obligation (ECO4) and the Great British Insulation Scheme (GBIS). Both are funded by energy suppliers and administered through approved installers, and both can cover measures that would otherwise cost several hundred to several thousand pounds.

ECO4 is targeted at lower-income households and those in properties with low energy efficiency ratings. It can fund loft insulation, cavity wall insulation, solid wall insulation, heat pumps and other measures at no cost or heavily subsidised cost to eligible households. Eligibility criteria are broader than many people expect – households in receipt of certain benefits, in properties with an EPC rating of D or below, or in certain council tax bands may qualify even if they do not consider themselves low income. The scheme has funded over 700,000 measures since its launch and remains active.

The Great British Insulation Scheme targets homes in EPC bands D to G and can contribute funding toward insulation improvements regardless of income, with the level of support dependent on EPC band and household circumstances. Checking eligibility for both schemes takes a few minutes and is worth doing before spending money on any insulation measure that might otherwise be funded. The Energy Saving Trust website provides a clear summary of available schemes and a tool for checking whether your property qualifies.