Older homes are full of character, but that character often comes with solid walls, sash windows, open chimneys and a distinct lack of insulation. The good news is that you do not have to choose between a warm, efficient house and a period property that still looks and feels like itself. With a sensible, phased approach, most older homes can cut their energy use significantly while keeping their original features intact.

Understand how your building behaves first

Before you order insulation or book an installer, spend some time learning what you are actually dealing with. The age, construction and materials of your home dictate which measures will work and which could cause damp, condensation or worse.

Older properties generally fall into two camps. Houses built before around 1919 usually have solid walls, which are designed to manage moisture differently from modern cavity walls. They rely on breathability: moisture moves through lime plaster, brick and stone rather than being trapped behind impermeable layers. Homes from the 1920s onwards often have cavity walls and are more forgiving of standard modern materials.

A professional retrofit assessment or a detailed Energy Performance Certificate can give you a starting point, but do not treat either as gospel. A surveyor who understands old buildings is worth far more than a generic checklist. Ask them where heat is actually escaping, and where moisture is going.

Insulate the easy wins: lofts and floors

Loft insulation remains the cheapest, quickest saving in most houses. If you have joists with nothing between them, top up to around 270mm of mineral wool. Keep the insulation out of the eaves airflow, and never block ventilation at the roof edge — trapped moisture in a cold roof space causes rot.

If your loft has been converted, insulation needs to sit between and above the rafters, which usually means rigid boards and a professional job. Do not simply stuff insulation against the underside of a roof deck without a ventilation gap.

Ground floors are often overlooked. Suspended timber floors over a ventilated void can be insulated by lifting boards and fitting mineral wool between the joists, supported on netting, while keeping the underfloor ventilation clear. Solid floors are harder and disruptive, so leave them unless you are already renovating.

Walls and windows: the bigger decisions

Solid wall insulation is where most of the heat is lost in a period home, but it is also where mistakes are expensive. External insulation changes the appearance of your house and may need planning consent in conservation areas or on listed buildings. Internal insulation loses floor space, disrupts rooms and can create cold bridges at junctions if not detailed carefully.

If you do insulate internally, use breathable materials such as wood fibre, cork or sheep's wool with a lime-based finish. Avoid cement renders and vapour-tight foams on solid walls, as these can trap moisture and lead to damp patches and decaying timbers.

For windows, the biggest gains usually come from secondary glazing rather than replacement. A well-fitted secondary pane keeps the original sash, reduces noise and draughts, and often performs comparably to double glazing. Where you are replacing windows, slim double-glazed units in timber frames suit period openings far better than bulky uPVC.

Draught proofing: cheap, quick and character-friendly

Draught proofing is the measure most people skip, and it is the one that makes a house feel instantly warmer. It is inexpensive, reversible, and does no harm to original fabric.

• Fit brush or silicone seals to sash windows, and consider spring seals in the gaps between frames.
• Use draught excluders or brush strips on external doors, including letterboxes and keyholes.
• Close off unused chimneys with a chimney balloon or sheep's wool draught excluder — but never block a flue that serves an open fire or stove.
• Seal gaps around pipework, cables and skirting boards with flexible sealant or lime mortar, depending on the surface.
• Fill gaps between floorboards with slivers of timber or flexible filler if the floor is not being lifted.

The aim is controlled ventilation, not a sealed box. Leave trickle vents and background ventilation in place, and open windows regularly to purge moisture.

Heating and controls: get more from what you have

Many older homes are heated far harder than they need to be because the system is poorly set up. Start with the basics. Have your boiler serviced, and ask the engineer to check that the flow temperature is set appropriately — condensing boilers only reach their stated efficiency when the return water is cool enough, often meaning a flow temperature of around 55 to 60°C.

Balance your radiators so that rooms heat evenly, and fit thermostatic radiator valves where you can. Zone your heating so bedrooms and unused rooms are not heated to the same level as living spaces. Smart controls help, but simple timers and thermostats set correctly will do most of the work.

Radiator reflector panels behind external walls, thermal curtains, and closing curtains at dusk all make a noticeable difference in draughty rooms. If you are considering a heat pump, insulation and draught proofing should come first — the smaller the heat demand, the smaller and cheaper the system you need.

Ventilation, moisture and phasing the work

As you make a house tighter, you must also manage moisture. Cooking, bathing and drying clothes release litres of water vapour daily, and in a well-sealed older home it will condense on the coldest surfaces. Use extractor fans in kitchens and bathrooms, keep trickle vents open, and consider a humidity-controlled whole-house system if damp becomes an issue.

Finally, phase the work sensibly. Start with the cheap, low-risk measures — draught proofing, loft insulation, heating controls — and monitor how the house responds over a winter. Then plan bigger interventions such as wall insulation or window upgrades alongside other renovation work, so scaffolding and disruption are shared.

Government grants and local authority schemes often cover part of the cost, and eligibility changes regularly, so it is worth checking before you commit. Done thoughtfully, an older home can be comfortable, affordable to run and every bit as full of character as the day it was built.