Start With the Draughts You Can Feel

Before you think about new windows or a heat pump, spend an afternoon walking around your home with the back of your hand. On a windy day, hold it near window frames, skirting boards, loft hatches, letterboxes and the gap under the front door. That cool tickle of air is money leaving the building. Draught-proofing is the cheapest energy upgrade there is, and in a typical Victorian terrace it can shave a noticeable slice off winter bills.

For sash windows, brush or foam draught strips fitted into the frame channels make a real difference, and they let the window still open. A silicone sealant bead around the inside of a fixed frame is quick and invisible. For doors, a good quality brush strip on the bottom edge plus a flexible seal around the frame works well. Chimneys are often overlooked: if you never light the fire, a chimney balloon or a capped vent stops a surprising amount of warm air vanishing upwards. Just remember ventilation matters, especially in kitchens and bathrooms, so never block deliberate trickle vents or air bricks.

Insulate the Loft Properly, Not Just Thickly

Heat rises, and an uninsulated loft can be responsible for around a quarter of a home's heat loss. If your loft insulation is thinner than 270mm, topping it up is one of the best-value jobs you can do. Rolls of mineral wool are inexpensive and a competent DIYer can lay them between and across the joists on a cold, dry day. Wear gloves, a mask and long sleeves — it itches.

The detail matters more than the depth, though. Push insulation right into the eaves without blocking the airflow from soffit vents, or you will create condensation and damp. Use plastic eaves guards or loft legs to keep a gap. Insulate the loft hatch itself with a rigid board glued to the back, and fit a draught seal around its edge. If you have a cold water tank or pipework up there, lag them before you bury them in insulation.

• Top up to at least 270mm, laid in two crossed layers to cover the joists.
• Keep a clear ventilation path at the eaves.
• Lag pipes and the cold water tank with foam or a jacket.
• Seal the loft hatch and insulate its back with rigid foam board.

Don't Forget the Hot Water Cylinder

A bare copper cylinder in an airing cupboard is a radiator you never asked for. Fitting a cylinder jacket of at least 80mm — and ideally a British Standard one — can cut the heat lost from your hot water by a large margin, keeping water hotter for longer and reducing how often the boiler fires. Fit it neatly with no gaps at the top, and leave the thermostat and immersion heater controls accessible. If your cylinder has a built-in foam layer already, you can still add a jacket on top for extra benefit.

While you are in the airing cupboard, check the first metre of hot water pipework leaving the cylinder. Foam pipe lagging there is cheap, easy to fit and pays back quickly, because that is where the heat loss is greatest. Do the same for any exposed pipes running through cold spaces such as garages or under suspended floors.

Take Control of Your Heating

Heating and hot water account for the majority of most household energy use, so even small improvements in how you run the system add up. A room thermostat set to around 18–20°C is comfortable for most people, and turning it down by just one degree can trim roughly 10% off heating bills over a year. Set your hot water cylinder thermostat to 60°C — hot enough to prevent legionella, and no hotter.

Heating controls have improved enormously. Smart thermostats and thermostatic radiator valves let you heat only the rooms you use, when you use them. Programme the heating to come on half an hour before you wake and to switch off half an hour before bed; a well-insulated home holds its warmth long enough for that to work. Zone the bedrooms separately from the living space if you can. And resist the temptation to leave the heating running low all day "to take the chill off" — timed, targeted heating is usually cheaper than a constant background hum.

Small Habits That Compound

Some of the simplest savings come from routine. Close curtains at dusk to trap warmth, but keep them clear of radiators so heat circulates. Bleed radiators each autumn so they heat evenly, and don't hang wet washing directly over them. Use the dishwasher and washing machine on full loads, wash at 30°C where fabrics allow, and dry clothes outside or on an airer in a ventilated room rather than in a tumble dryer. A shower instead of a bath uses far less hot water.

Where you do use lighting, swap remaining halogen bulbs for LEDs — they use around 90% less energy and last for years. Put appliances that stay on standby onto a switched extension lead. None of these steps is dramatic, but together they quietly reduce the base load running all year.

Knowing When to Call in a Professional

Much of what is described here is genuinely within reach of a careful DIYer, but some jobs benefit from expert hands. Cavity wall insulation, solid wall insulation, underfloor insulation and any work around a boiler or flue should be done by someone qualified, and older homes with solid walls or unusual construction need a breathable, considered approach rather than a one-size-fits-all fix. If your home is listed or in a conservation area, check before altering windows or external fabric.

A whole-house assessment can also reveal the order in which improvements make sense, so you do not spend money on the wrong thing first. Pair these measures with natural, breathable materials where you can — sheep's wool or wood fibre insulation, lime-based plasters and draught seals in timber frames — and you will improve efficiency while keeping the character and comfort that make an old house worth living in.