Window Sealing in Warsaw — Seal Replacement and Draught-Proofing

Cold air creeping through a closed window, condensation on the glass every morning, street noise louder than it should be? The seal has most likely reached the end of its life. Over time the rubber hardens, cracks and flattens — and the window stops holding heat. Replacing a seal takes 15–30 minutes per sash and costs a fraction of a full window replacement. We work across Warsaw — from Ursynow to Bemowo. We match the seal profile to the specific window system: EPDM, silicone or TPE. The result is a tight-fitting sash, a quieter room and lower heating bills.

How much does seal replacement cost and what affects the price

The price depends on the length of seal required (measured in linear metres), the profile type and the number of sashes. A standard window needs roughly 3–4 linear metres. A balcony door takes more. If the seal is non-standard — for example for older German or timber windows — the price is slightly higher because of the material cost.

The work price includes: removing the old seal, cleaning the groove and fitting the new one. The seal itself is charged separately, but it is an inexpensive consumable. Fasteners are included. Waste removal and material delivery are extra. Current prices below.

Take a close-up photo of the window and the seal — the technician will identify the profile and quote a price before arriving.

How seal replacement works: step by step

Sealing is not just pushing rubber into a groove. The right profile, a clean channel and careful fitting without stretching or joins are what make the difference:

1. Inspection and diagnostics. The technician checks the seal condition around the full perimeter of the sash and frame. He identifies the profile type — every manufacturer (Rehau, KBE, Veka, Salamander) has its own groove shape and seal cross-section.
2. Removing the old seal. The worn rubber is carefully pulled from the groove. If it is glued in, we use a scraper without damaging the plastic.
3. Cleaning the groove. The channel is wiped clean of dirt, dust and adhesive residue. This is critical — a dirty groove means the new seal will not seat properly and will come loose.
4. Measuring and selecting the profile. We measure the exact perimeter length. We select the seal by profile: EPDM (synthetic rubber — the most durable, 10–15 years), silicone (best for timber windows), TPE (thermoplastic — budget option, 5–8 years).
5. Cutting and fitting. The seal is inserted in one continuous piece with no joins — this is the key point. The only joint is at the top corner of the sash. The rubber must not be stretched or allowed to sag.
6. Checking the pressure. We close the sash and test the fit with a sheet of paper around the full perimeter. The paper should require noticeable force to pull out. If it slips anywhere, we adjust.
7. Lubrication and advice. We apply silicone lubricant to the new seal to extend its service life. We explain how to maintain it: wipe and lubricate every six months.

Common mistakes when sealing windows

Seal replacement looks straightforward, but mistakes happen frequently — and then the job has to be redone:

• Wrong seal profile. A “universal” seal from the market that does not match the groove. It barely holds, falls out within a month. Every system (Rehau, Veka, KBE) requires its own profile.
• Cheap foam seal tape. Self-adhesive foam from a DIY store is a temporary fix for a couple of months. It compresses, peels off and does not provide proper clamping pressure.
• Silicone sealant instead of a proper seal. Squirting silicone into the groove or along the sash-to-frame joint does not work: the sash stops opening properly and the silicone peels off in strips.
• Dirty groove. The new seal fitted on top of dust and old residue. Within weeks it starts popping out and does not sit flush.
• Multiple joins around the perimeter. Seal fitted in pieces with several joints. Every joint is a potential draught point. The correct method is one continuous piece for the entire perimeter.
• Stretching during fitting. The seal is pulled tight to make it reach. A week later it shrinks back and gaps appear in the corners.

What to prepare before the technician arrives

The work is clean and quick, but a few things will speed up the process:

• Clear the windowsill of anything that prevents the sash from opening fully — plants, lamps, decorations.
• Pull back curtains and blinds so the technician can work freely.
• If there is a fly screen on the window, remove it beforehand.
• Work out which windows are draughty. A simple test: close the window, hold your palm along the sash perimeter — wherever you feel air movement the seal has failed.
• Check every window in the flat — seals often wear out on all of them at the same time. It is cheaper to replace them in one visit.
• If you know the window brand (Rehau, Veka, KBE, Salamander) tell the technician in advance so he brings the right profile.
• Have access details ready: entry code and parking information.
• Pets are best kept in another room — the technician will be opening windows.
• If the balcony door seal also needs replacing, mention it in advance — the process is the same.
• Consider whether the hardware should be adjusted at the same time — after a new seal is fitted it often makes sense to fine-tune the clamping pressure.

A real case: window sealing in a Mokotow flat

The owner of a flat in Mokotow called with a complaint: the bedroom was cold in winter despite the heating working fine. Every morning there was condensation on the glass and the windowsill was wet. The windows had been installed seven years earlier and had never been serviced.

On inspection we found that the seals on three sashes had flattened and lost their elasticity — you could press a finger into the gap between the sash and the frame. On one window the seal had come out of the groove entirely and was hanging in a loop. The profile was Rehau Blitz, requiring a seal with a specific cross-section. We replaced the seals on all three windows: removed the old ones, thoroughly cleaned the grooves and fitted new EPDM seals in one continuous piece per sash. While we were at it we tightened the hinges — two sashes had sagged slightly. After replacement we tested the pressure with paper — the sheet held firmly around the entire perimeter. The job took about 40 minutes. The client messaged three days later: the condensation had gone, the bedroom was noticeably warmer and street noise had dropped significantly.

Frequently asked questions

How do I know the seal needs replacing?

Key signs: draughts with the window closed, condensation on the glass, street noise louder than before. Visually — the rubber is cracked, flattened, misshapen or has popped out of the groove.

Which seal is best — EPDM, silicone or TPE?

EPDM (synthetic rubber) is the best choice for uPVC windows: it lasts 10–15 years and handles temperature swings well. Silicone is good for timber frames. TPE is the budget option but less durable (5–8 years).

How long does the replacement take?

One sash — 15–20 minutes. A typical flat with 4–5 windows — an hour and a half to two hours, including groove cleaning and testing.

Can I replace the seal myself?

Technically yes, if you select the right profile and buy a quality seal. In practice the main difficulty is identifying the correct cross-section. There is no such thing as a universal seal, and the wrong profile simply will not hold.

How often should seals be replaced?

EPDM — every 10–15 years. TPE — every 5–8 years. Wiping and lubricating with silicone every six months extends the lifespan. Keeping windows permanently in winter mode wears the seal out faster.

Will a new seal reduce noise?

Yes, noticeably. A worn seal lets through not just air but also sound. After replacement street noise drops — especially noticeable in flats on busy roads.

Does the window need adjusting after a new seal?

Recommended. A new seal is thicker than the old flattened one, so clamping pressure may be too high. The technician will adjust the eccentric cams so the sash closes smoothly and pressure is even.

Who does the work and what guarantees we offer

Window sealing is carried out by technicians who work with window systems every day — Rehau, Veka, KBE, Salamander, Schuco. We know which seal profile fits each system and always carry several sizes. We arrive with spare material, groove-cleaning tools and silicone lubricant. We cover all of Warsaw — from Praga Poludnie to Wlochy. We guarantee a tight-fitting seal and no draughts. If within a month the seal settles or starts letting air through, we come back and fix it free of charge. Call or message us — we typically reply within an hour.