Draught-Proofing in Ireland: Where to Start, What It Saves

Why draughts cost you a fill

If your oil-heated home feels chilly even when the boiler's been running, draughts are usually the culprit. Cold air sneaks in around doors, windows and unused chimneys, your boiler works harder to keep up, and you burn more oil for the same warmth. Draught-proofing is the cheapest, highest-return job most Irish homeowners can do, and a lot of it is genuine DIY.

The Energy Saving Trust puts the saving from draught-proofing a typical home at a meaningful slice off your heating bill each year, and SEAI lists it among the lowest-cost first steps before bigger upgrades. In oil terms, that can be the difference of part of a fill over a heating season. It won't transform a leaky old cottage on its own, but euro for euro it's hard to beat.

Start with the biggest, cheapest wins

Unused chimney

An open, unused chimney is like leaving a window open all winter. Warm air you've paid to heat goes straight up and out. A chimney draught excluder (an inflatable "balloon" or a fitted wool/foam cap) seals the flue and is one of the best-value buys going, often a small spend for a noticeable drop in that cold downdraught.

Two rules: only seal a chimney that's genuinely out of use, and leave the balloon's tag hanging down as a reminder so nobody lights a fire under it. If the fireplace is ever used, take it out first.

Doors

• Front and back doors: brush strips or a draught excluder along the bottom, plus self-adhesive foam or rubber seal around the frame.
• Keyholes and letterboxes: a covered keyhole escutcheon and a letterbox brush flap close two surprisingly chilly gaps.
• Internal doors to unheated rooms: a simple fabric "sausage" excluder keeps heat where you want it.

Windows

Self-adhesive foam or wiper-blade style strips around opening sashes cut the whistle around old timber and uPVC frames. For draughty older windows, removable silicone gap filler or heavy lined curtains add another layer for very little money.

DIY vs fitted: what to do yourself

Most of the list above is comfortable DIY with a tape measure, a knife and an afternoon. Foam strips, brush seals, letterbox flaps and chimney balloons all come with instructions and cost very little.

Get a professional for trickier jobs: draught-proofing sash windows properly, sealing around suspended timber floors, or anything involving the boiler flue or vents. And one important caution: never block permanent air vents that serve an oil boiler, stove or any combustion appliance. Those vents are there for safe combustion. Seal the draughts you can see, leave the purpose-built ventilation alone, and if you're unsure which is which, ask an OFTEC-registered technician.

Rough savings, set realistic expectations

Think of draught-proofing as trimming waste rather than slashing your bill in half. Combined with a couple of other cheap moves, the effect adds up:

• Cylinder jacket (lagging): an insulating jacket on your hot-water cylinder is one of the fastest payback jobs in the house.
• Pipe lagging: foam sleeves on exposed hot pipes keep heat in the water, not the press.
• Radiator reflector panels behind rads on external walls bounce heat back into the room.
• Smart heating controls and smart radiator valves (TRVs): these don't stop draughts, but they stop you heating empty rooms, so the oil you do burn goes further.

None of these are a substitute for the draught-proofing itself, but together they mean less oil for the same comfort. For a closer look at the gadget side, browse our gadget guides.

A sensible order of attack

1. Cap the unused chimney.
2. Seal door bottoms, frames, keyholes and the letterbox.
3. Strip the worst draughty windows.
4. Jacket the cylinder and lag exposed pipes.
5. Add reflectors and tune your controls.

Do the first three on a free weekend and you'll feel the difference before the next cold snap.

Don't undo the good work by running dry

The other half of using less oil is never paying for a panicked emergency fill or a boiler lockout after a run-out. Keep an eye on your tank so you can see when you'll run out, set a price-drop alert so you're ready when prices ease, and compare local prices by county before you order. Seal the leaks, then buy on your own terms.