Window Sealing

Window sealing should not begin with arbitrary sealant, automatic gasket replacement or maximum hardware compression. The first task is to establish where unwanted air is actually passing. Leakage may occur between sash and frame, result from gasket condition, or be located at the frame-to-wall junction.

The technician call-out and diagnostics are free. After inspection we explain the scope and price before paid work begins. If the cause is clear, the correct materials or original parts are available and the repair can be carried out on site, the agreed work may be completed during the same visit.

There is a draught – what actually needs sealing?

A draught is a symptom, not a diagnosis. Two windows with apparently similar air movement may require completely different repairs. We therefore separate three main areas during diagnostics:

• sash-to-frame contact – sash position, gasket contact and locking-point operation;
• the gasket – damage, permanent deformation, position and whether that gasket is designed for service replacement;
• frame-to-wall junction – accessible areas of the window-to-reveal connection when symptoms indicate leakage there.

This distinction avoids a common mistake: replacing a serviceable gasket when compression is the issue, or increasing compression when air is actually entering beside the frame.

How should windows be sealed for winter?

Online advice often reduces “winter sealing” to turning cams or rollers to a so-called winter setting. Technically, that is too simplistic. Many hardware systems provide adjustable compression, but the correct setting depends on the hardware design, sash geometry and gasket condition.

The goal is therefore not maximum pressure but correct, even sash-to-gasket contact. If the handle becomes unusually hard to operate, the sash rubs or compression is uneven, window adjustment may be the correct solution rather than further tightening.

When is gasket replacement required?

Cracking, tearing, permanent flattening, hardening or displacement can indicate that a gasket needs replacement. Window age or a draught alone is not enough to make that decision.

If diagnostics confirms a gasket fault, the appropriate service is window gasket replacement. We identify the system and specific sealing position. Where that gasket is designed for service replacement, we use a new, original manufacturer product intended for the identified system – not an arbitrary profile chosen merely because its shape looks similar.

When is the problem around the frame rather than in the window itself?

The window-to-reveal connection is a separate part of the airtightness system. If a clear draught occurs at the frame-to-wall junction, below the sill or at another accessible installation-zone location, sash adjustment or gasket replacement alone may not solve the problem.

We assess the accessible leakage point and select a repair within our service scope. We do not simply cover the symptom with an arbitrary material without establishing where the air is actually passing.

What can professional window sealing include?

• air-leak diagnostics – locating unwanted air movement;
• geometry and compression checks – when the problem occurs at sash-to-frame contact;
• hardware adjustment – within the adjustment range intended for the identified system;
• gasket replacement – when gasket condition is the actual cause and the component is designed to be replaced;
• sealing an accessible frame junction – where the source is in the installation zone and the repair falls within our scope.

Not every leak requires every operation. A good repair means carrying out what the diagnosed cause requires rather than adding work “just in case”.

Can window sealing reduce heat loss?

It can when part of the heat loss results from uncontrolled air leakage. Air permeability is a distinct performance characteristic of a window. Repairing an air leak does not, however, change the thermal transmittance of the glazing unit or frame profile, so we do not promise an effect the repair cannot technically provide.

Cold glass, condensation and mould are not the same as a draught

A cold sensation near the glazing does not by itself prove air movement. Likewise, condensation, moisture or mould do not automatically prove that a window is leaking air. They are influenced by factors including surface temperature, indoor humidity and ventilation.

For that reason we do not recommend “sealing everything” as a response to misted glass. Reducing air supply without adequate ventilation can worsen moisture conditions. Where controlled air supply is required by the ventilation arrangement, window ventilators may form part of the solution.

What can you check yourself?

• Inspect the gaskets for cracks, tears, permanent flattening and displaced sections.
• Check sash operation for rubbing, obviously uneven operation and unusually high handle resistance.
• Locate the draught – determine whether it is felt at sash-to-frame contact or beside the frame.
• Do not remove the gasket merely as a test – systems use different gasket constructions and installation methods.

These observations help describe the symptom but do not replace diagnostics. We also do not recommend testing for air leakage with an open flame.

Original parts instead of arbitrary substitutes

We service constructions and systems from many brands, including VEKA, Salamander, Aluplast, REHAU, Drutex, Oknoplast, MS Więcbork, Schüco and Aluprof, as well as hardware from Roto, SIEGENIA, Winkhaus, MACO and GU.

If a repair requires a gasket, hardware component or other part to be replaced, we first identify the manufacturer and system. We use new, original products from the correct manufacturer intended for the identified solution. We do not substitute an arbitrary component merely because it looks similar or can physically be fitted.

Sealing PVC, timber and aluminium windows

We diagnose air leaks in supported PVC windows, timber windows and aluminium windows. Frame material alone does not determine the cause; the specific construction, hardware system, sealing design and leakage location matter.

For timber windows we provide functional repair and servicing. We do not renovate, restore, sand or repaint timber frames.

How does our service work?

The service process is simple and transparent — six steps from first contact to warranty:

• Contact – fill in a short form or call us. We call back within approximately 15 minutes.
• Free on-site diagnostics – a technician arrives at the agreed time and assesses the condition on site.
• We explain the cause – we show you exactly what needs to be repaired.
• We present the cost – after diagnostics we provide an exact quote. No hidden fees.
• We carry out the repair – after your approval we complete the work, most often during the same visit.
• You verify the result – we test the outcome together. You receive a service report, a warranty on the work performed, and the manufacturer's warranty on original parts.

Where do we provide window sealing?

We provide the service across our active regions and cover 120+ cities, including Warsaw, Kraków, Katowice and Silesia, Poznań and Łódź. We also serve other locations within our current service area. Check our service area →

How much does window sealing cost?

Window sealing starts from 38 PLN. The exact price depends on the source of the leak, number of windows, required original parts or materials and scope of work. The technician call-out and diagnostics are free, and the price is provided before paid work begins.

Indicative prices for other work are available on our pricing page. After registration we contact you within about 15 minutes. Completed work is covered by a written guarantee of up to 5 years; the applicable period depends on the service performed.