Draughty Windows & Sticky Gaskets: Stop the Ghost Drafts Without DIY Disasters

You've sealed the obvious gaps. The draught still comes through.

That's a ghost draught: the cold air slipping past the back edge of the window frame where the gasket meets the sash. Not the visible perimeter seal most people check. The one hidden at the back, often painted over or compressed from years of use.

We see this constantly. Windows that look properly sealed but pull cold air through channels most people never think to inspect.

The Real Cost of Ghost Draughts

Failed gaskets don't just feel annoying. They cost money.

A window can look “closed” and still leak. The heating runs longer to hold temperature—and you feel colder than the thermostat says because moving air strips heat off you fast.

As a rough rule, persistent draughting from failed seals can push heating bills up by 10–15%—especially on exposed elevations and older aluminium systems with tired EPDM profiles.

Not just comfort. Efficiency.

Where Ghost Drafts Actually Come From

The perimeter gasket everyone checks isn't usually the problem. It's the internal rebate seal: the gasket sitting in the channel where the sash closes against the frame. This seal compresses differently depending on how the window was adjusted during installation.

On tilt and turn windows, these seals sit at multiple points around the frame. When one section fails or compresses unevenly, air moves through the gap between the glass unit and the frame structure itself. You won't see it. You'll feel it as a persistent cold spot that doesn't match any visible gap.

Aluminium windows have thermal breaks built into the frame sections. When gaskets fail at these junctions, cold air bypasses the thermal barrier entirely. The frame conducts cold, and the failed seal lets air through: double exposure.

Common ghost draught locations:

• Where the sash rebate meets the frame on the hinge side
• At the top corner joints on tilt mechanisms
• Behind fixed glazing beads that were sealed during installation
• Where frame extensions meet the structural opening

These aren't accessible with standard weatherstripping. The seal sits inside the window assembly.

Why Windows Feel Glued Shut

Sticky gaskets happen when EPDM or silicone seals break down and become tacky rather than flexible. The rubber degrades from UV exposure, temperature cycling, and contamination from cleaning products. Instead of compressing and releasing smoothly, the gasket surface becomes adhesive.

You pull the handle. The window resists. It feels stuck.

This isn't a locking problem. It's material degradation creating friction between the gasket and the frame surface. Forcing it risks tearing the gasket or damaging the sash alignment: then you've got both problems.

What causes gasket degradation:

• Silicone-based cleaning sprays that leave residue on rubber seals
• Direct UV exposure on south and west-facing windows
• Thermal expansion cycles that crack the seal surface
• Painted-over gaskets from previous redecoration work
• Moisture trapped between gasket and frame causing surface breakdown

Windows installed before 2010 often used different gasket compounds than current specifications. These older materials don't have the same UV resistance. They fail faster in exposed positions.

The Bank Card Trick

Before you consider replacing gaskets, try freeing them mechanically.

Take an old bank card: expired credit card, store loyalty card, anything rigid but not sharp. Slide it gently along the seal between the gasket and the frame surface where they're sticking. Work around the entire perimeter slowly.

You're breaking the adhesive bond without tearing the rubber. The card is thin enough to slip into the gap but rigid enough to separate the surfaces. This works when the gasket material is still structurally sound but has developed surface tackiness.

Don't use a screwdriver or metal tool. You'll score the gasket or chip the frame finish. Don't use a knife: too easy to cut through the seal entirely.

If the gasket releases and the window operates smoothly afterward, clean both surfaces with isopropyl alcohol to remove residue. Let it dry completely. The tackiness shouldn't return immediately.

If the card won't slide in or the gasket tears when you try, the material has failed structurally. Replacement needed.

Why DIY Sealing Tape Makes Things Worse

Hardware stores sell adhesive foam tape marketed for sealing window gaps. Applying this over existing gaskets or around window frames creates a bigger problem than it solves.

The tape blocks ventilation paths designed into the window system. Modern windows include controlled drainage channels that allow condensation to exit the frame cavity. Sealing over these traps moisture inside the frame structure.

Trapped moisture condenses on cold surfaces inside the frame. It pools in the bottom channel. It saturates insulation materials. It promotes corrosion on metal components and creates conditions for mould growth inside the sealed cavity.

You've fixed the draught. You've created a moisture problem that will damage the window frame from inside.

What happens when you seal drainage paths:

• Water collects in the bottom frame channel with no exit route
• Frame insulation materials become saturated and lose thermal performance
• Condensation forms on interior metal components, causing corrosion
• Mould grows on wooden frame elements in damp conditions
• Ice forms in the cavity during freezing conditions, expanding and cracking seals

Drainage slots aren't defects. They're engineered features. Blocking them compromises the window system's ability to manage the moisture it's designed to handle.

Adhesive foam also prevents proper window operation on opening sections. It compresses when you close the window, then prevents smooth opening because it's stuck in the compressed position. You're back to forcing stuck windows: now with a seal you've created yourself.

Condensation Between Glass Panes

If you see moisture, fog, or water droplets between the glass layers of a double or triple-glazed unit, the seal has failed. Not the gasket around the frame: the edge seal of the insulated glass unit itself.

This isn't something you fix. The entire glazing unit needs replacement.

Insulated glass units are factory-sealed with structural silicone or polyurethane at the perimeter. They're filled with argon or krypton gas for thermal performance, then sealed permanently. When that seal breaks, outside air enters the cavity. Moisture comes with it.

You can't reseal it from the outside. You can't drill a hole to "let it dry out." The desiccant material inside the spacer bar is saturated. The inert gas has escaped. The thermal performance is gone.

Units typically fail at the corner joints where the spacer bar sections meet. Thermal stress causes microscopic cracks. Water vapour migrates through. Once it starts, it accelerates.

Signs of failed unit seals:

• Visible condensation between panes that appears and clears with temperature changes
• White mineral deposits on the inside glass surface
• Permanent fogging that doesn't clear
• Water droplets that run down between the panes
• Distortion visible through the glass from delaminating coatings

This happens to aluminium window systems particularly often because the frame conducts more temperature change to the glass edge. The seal experiences greater thermal cycling stress.

For emergency window repair in London, we stock common glazing unit sizes and can measure for non-standard replacements. Most units are available within 3-5 days for standard configurations.

Tilt and Turn Window Specific Issues

Tilt and turn mechanisms create additional seal points that casement windows don't have. The sash needs to seal in both tilt and turn positions: different compression patterns on the same gasket system.

When these windows develop ghost drafts, it's usually at the hinge-side vertical seal or the bottom horizontal seal in tilt mode. The multi-point locking system compresses the gasket unevenly if the sash alignment has shifted.

Forcing a sticky tilt and turn window risks damaging the tilt mechanism itself. These use pivot points and locking cams that can bend if the sash is forced while partially engaged. Then you need mechanism replacement, not just gasket service.

Tilt and turn complications:

• Gaskets must seal in two different sash positions
• Hinge-side seals wear faster from repeated tilt operation
• Multi-point locks can mask alignment problems until gaskets fail
• Mechanism binding often presents as sticky gasket symptoms
• Adjustment screws affect both operation and seal compression

We diagnose tilt and turn window issues by checking sash alignment before addressing seals. If the sash sits out of square, new gaskets won't solve the draught problem: the compression will still be uneven.

For tilt and turn window repair in London, alignment typically requires adjustment at three points: hinge-side vertical, lock-side vertical, and bottom horizontal. All three affect seal performance.

When Professional Assessment Makes Sense

Ghost drafts from internal seals require frame disassembly to access properly. Sticky gaskets need assessment to determine if the issue is surface degradation or structural failure. Failed glazing units need measurement and replacement.

These aren't necessarily complex repairs. They're specific to window type and require accessing components that weren't designed for repeated maintenance.

Attempting DIY solutions on these particular problems risks creating additional damage that increases repair costs. Forcing stuck windows bends mechanisms. Applying inappropriate sealants traps moisture. Attempting to reseal failed units wastes time and materials.

We handle aluminium window repair in London for commercial and residential installations: including obscure systems where parts availability determines the repair approach. Sometimes replacement is actually simpler than sourcing discontinued gasket profiles.

The assessment tells you whether you need new gaskets, frame adjustment, glazing unit replacement, or complete window replacement. That's worth knowing before attempting fixes that might not address the actual problem.

Get in touch if you're dealing with persistent drafts that don't match visible gaps, windows that won't open smoothly despite functioning locks, or condensation appearing inside sealed glass units. We'll diagnose what's actually failed and what it takes to fix it properly.