How to stop draughts: Window seal and installation quality explained
  • NexGen Windows

    How to stop draughts: Window seal and installation quality explained

    If your home feels cold near the windows despite the heating running, a failed seal or poor installation is almost certainly the cause.
The fix depends on how far the problem has gone. In most cases, draughty windows in Swindon homes fall into one of two categories: degraded seals on otherwise sound frames, or older units that have reached the end of their useful life and need full replacement. This guide covers how to tell the difference, what both options cost you, and when it makes sense to call in an expert.
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Why Swindon homes feel the cold more than you'd expect

Swindon sits within Wiltshire's open vale, exposed to south-westerly airflow off the Downs. Winters here bring consistent damp and chill, with January average highs of just 6.3°C and lows dropping to around 1.4°C. February is the windiest month of the year, with average wind speeds reaching 18.4 km/h. That persistent wind matters a great deal when your window seals are compromised, because cold air under pressure finds every gap. The result is a home that feels draughty despite the heating being on, with warm air escaping through the same gaps that cold air enters. Every degree you lose through a gap is money spent on heating air you'll never benefit from. Across a Wiltshire winter that runs from October through to March, that adds up fast.

What causes window seals to fail?

Seals do not last forever. Most window seals last around 10 years under normal conditions, but exposure to harsh weather accelerates degradation. For homes in Swindon, the combination of damp winters and wind means seals often deteriorate faster than average. The main reasons for failure are:
Cause What you notice
Rubber gasket shrinkage Visible gap at the frame edge
UV degradation of seals Brittleness, cracking at corners
Frame movement over time Draughts on one side of the window
Failed perimeter sealant Cold spots, damp patches on sill
Poor original installation Draught present from day one
With age, seals degrade and allow air to leak in, stopping insulation and warping frames, all of which lead to draughts. Poor initial installation creates immediate draught problems that only worsen with age. The key point: a draught is never just a draught. It signals that moisture, noise and heat loss are all working against your home.

How to check if your windows in Swindon are draughty

You do not need specialist tools. Hold a lit candle or a thin strip of paper near the window frame on a windy day. If the flame flickers or the paper moves, you have found your gap. Run this test around the full perimeter, including the corners and the point where the frame meets the wall.

Condensation between the panes is a separate but related problem. Persistent fogging with visible water droplets signals advanced seal failure requiring immediate attention. At this stage, the sealed unit itself has failed and cannot be repaired with sealant alone.

Why installation quality determines how warm your home stays

Draught-free windows are not just about the product. Installation is where most draughts are created or prevented. Poorly fitted frames leave gaps at the reveal, compressed seals fail within months, and misaligned sashes never close flush.
At NexGen Windows, every installation is carried out by trained fitters and backed by a 10-year guarantee. NexGen is also a CERTASS member, meaning all work is compliant with current building regulations and you receive a certificate confirming this. The team covers all areas within 30 miles of Swindon, including Chippenham, Marlborough, Devizes and Cirencester.

Our double glazed windows are specified with compression seals and premium weather-rated frames designed to handle the Wiltshire climate long-term. If you prefer a more traditional look, our flush windows offer a 7-chamber profile with one of the highest weather ratings achievable.

Seal repair vs. full window replacement: which is right for you?

Scenario Best option
Seal is soft, frame is sound Re-seal with silicone, monitor
Condensation between panes Replace glazed unit or full window
Frame is warped or cracked Full replacement
Windows over 15–20 years old Full replacement likely more cost-effective
Draughts on newly installed windows Installation defect, request rectification
Double glazing installed before 2000 will probably need draught proofing or replacement. Sealing drafty windows typically reduces heating costs by 10–20% depending on how severe the draughts were initially. For windows at end of life, the Energy Saving Trust estimates that installing A++ rated double glazing in a single-glazed semi-detached house could save around £95 per year.

Will new windows reduce traffic noise too?

Yes. Draught-free windows and acoustic performance go hand in hand. A sealed unit with no air gaps blocks sound transmission far more effectively than one with failed perimeter sealant. Our casement windows are available in double or triple glazing, both of which support noise reduction alongside energy efficiency improvements.
Get a free quote to stop draughts in your Swindon home

If you are losing heat through your windows, contact NexGen Windows for a free, no-obligation quote. There is no hard selling, and you can speak directly with the owners about your project. Call 01793 977030 or visit the showroom at 9 Clive Parade, Cricklade Road, Swindon SN2 1AJ.

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