Cold air slipping through a shut window, condensation on the glass each morning, street noise stronger than it ought to be? Most likely the seal has worn out. With time, the rubber goes hard, cracks and loses its shape — and the window stops keeping the heat in. Replacing a seal takes 15–30 minutes per sash and costs far less than changing the whole window. We work across Warsaw — from Ursynow to Bemowo. We choose the seal profile to match the exact window system: EPDM, silicone or TPE. The end result is a snug sash, a quieter room and smaller heating bills.
How much does seal replacement cost and what affects the price
The cost depends on how much seal is needed (measured in linear metres), the profile type and the number of sashes. A standard window needs around 3–4 linear metres. A balcony door needs more. If the seal is non-standard — for example for older German or timber windows — the price is a bit higher because the material costs more.
The labour price covers: taking out the old seal, cleaning the groove and installing the new one. The seal itself is billed separately, but it is a low-cost consumable. Fasteners are included. Waste removal and material delivery are charged extra. Current prices below (compatible with Porta, VOX, Erkado and similar).
| Service | min | max |
|---|---|---|
| Window sealing | 25 zł/mb | 40 zł/mb |
| Window adjustment | 30 zł | 60 zł |
| Window repair | 150 zł | 400 zł |
Take a close-up photo of the window and the seal — the technician will identify the profile and give you a price before coming out.
How seal replacement works: step by step
Sealing is more than just pressing rubber into a groove. The correct profile, a clean channel and careful fitting without stretching or joins are what really matter:
- Inspection and diagnostics. The technician checks the condition of the seal around the entire sash and frame. He identifies the profile type — each manufacturer (Rehau, KBE, Veka, Salamander) has its own groove shape and seal cross-section.
- Removing the old seal. The worn rubber is gently pulled out of the groove. If it has been glued in, we use a scraper without harming the plastic.
- Cleaning the groove. The channel is cleaned of dirt, dust and adhesive remains. This part matters — if the groove is dirty, the new seal will not sit properly and will start coming out.
- Measuring and selecting the profile. We measure the exact perimeter length. We choose the seal by profile: EPDM (synthetic rubber — the longest-lasting, 10–15 years), silicone (best for timber windows), TPE (thermoplastic — budget option, 5–8 years).
- Cutting and fitting. The seal is fitted in one continuous piece with no joins — that is the key detail. The only joint is at the top corner of the sash. The rubber must not be stretched or left sagging.
- Checking the pressure. We close the sash and test the fit with a sheet of paper around the full perimeter. The paper should take noticeable force to pull out. If it slips anywhere, we make an adjustment.
- Lubrication and advice. We apply silicone lubricant to the new seal to help it last longer. We explain how to look after it: wipe and lubricate it every six months.
Common mistakes when sealing windows
Replacing a seal looks simple, but people get it wrong all the time — and then everything has to be done again:
- Wrong seal profile. A “universal” seal from the market that does not fit the groove. It barely stays in place and falls out within a month. Every system (Rehau, Veka, KBE) needs its own profile.
- Cheap foam seal tape. Self-adhesive foam from a DIY store is a short-term patch for a couple of months. It compresses, peels away and does not give proper clamping pressure.
- Silicone sealant instead of a proper seal. Pumping silicone into the groove or along the sash-to-frame joint does not solve the problem: the sash stops opening properly and the silicone starts peeling off in strips.
- Dirty groove. The new seal is installed over dust and old residue. After a few weeks it begins to pop out and does not sit flat.
- Multiple joins around the perimeter. Seal installed in sections with several joints. Every joint is a possible draught point. The right way is one continuous piece for the whole perimeter.
- Stretching during fitting. The seal is pulled to make it reach. A week later it shrinks back and gaps show up in the corners.
What to prepare before the technician arrives
The job is clean and fast, but a few simple things will make it go quicker:
- Clear the windowsill of anything that stops the sash from opening fully — plants, lamps, decorations.
- Pull back curtains and blinds so the technician has free access.
- If there is a fly screen on the window, take it off beforehand.
- Figure out which windows are draughty. A simple test: close the window, move your palm along the sash perimeter — where you feel air movement, the seal has failed.
- Check every window in the flat — seals often wear out on all of them around the same time. Replacing them in one visit is cheaper.
- If you know the window brand (Rehau, Veka, KBE, Salamander) tell the technician in advance so he brings the correct profile.
- Have access details ready: entry code and parking information.
- Pets are better kept in another room — the technician will be opening windows.
- If the balcony door seal also needs replacing, say so in advance — the process is the same.
- Think about whether the hardware should be adjusted at the same time — after fitting a new seal, 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 us with one complaint: the bedroom was cold in winter even though the heating was working properly. Every morning there was condensation on the glass and the windowsill was wet. The windows had been installed seven years earlier and had never had any servicing.
During inspection we found that the seals on three sashes had flattened and lost their spring — you could push a finger into the gap between the sash and the frame. On one window the seal had come completely out of the groove and was hanging in a loop. The profile was Rehau Blitz, which needs a seal with a specific cross-section. We replaced the seals on all three windows: removed the old ones, cleaned the grooves thoroughly and fitted new EPDM seals in one continuous piece per sash. While we were there, we also tightened the hinges — two sashes had dropped slightly. After replacement we checked the pressure with paper — the sheet held firmly around the whole perimeter. The work took about 40 minutes. The client sent a message three days later: the condensation was gone, the bedroom felt clearly warmer and the street noise had dropped a lot.
Frequently asked questions
How do I know the seal needs replacing?
Main signs: draughts when the window is closed, condensation on the glass, street noise louder than before. Visually — the rubber is cracked, flattened, deformed or has come out of the groove.
Which seal is best — EPDM, silicone or TPE?
EPDM (synthetic rubber) is the best option for uPVC windows: it lasts 10–15 years and copes well with temperature changes. Silicone works well for timber frames. TPE is the budget option but does not last as long (5–8 years).
How long does the replacement take?
One sash — 15–20 minutes. A standard 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 choose the right profile and buy a good-quality seal. In real life the main problem is identifying the correct cross-section. There is no universal seal, and the wrong profile simply will not stay in place.
How often should seals be replaced?
EPDM — every 10–15 years. TPE — every 5–8 years. Wiping and lubricating with silicone every six months helps them last longer. Keeping windows permanently in winter mode wears the seal out faster.
Will a new seal reduce noise?
Yes, quite noticeably. A worn seal lets through not only air but sound as well. After replacement, street noise drops — especially in flats on busy roads.
Does the window need adjusting after a new seal?
Yes, recommended. A new seal is thicker than the old flattened one, so the clamping pressure may become too high. The technician will adjust the eccentric cams so the sash closes smoothly and the pressure is even.
Who does the work and what guarantees we offer
Window sealing is done 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 seal and no draughts. If within a month the seal settles or starts letting air through, we come back and sort it out free of charge. Call or message us — we usually reply within an hour.