5 najczęstszych błędów przy wyborze windows – tego unikaj w 2025 roku!

Selection windows to jedna z kluczowych decyzji podczas budowy lub remontu domu. To inwestycja na długie lata – nie tylko estetyczna, ale przede wszystkim funkcjonalna i energetyczna. Niestety, wielu inwestorów popełnia przy tym błędy, które mogą sporo kosztować. Sprawdź, czego unikać, by nie żałować później swojej decyzji.

❌ 1. Wybór najtańszych windows z marketu

Kuszące ceny w marketach budowlanych potrafią skusić niejednego. Problem w tym, że najtańsze windows często wykonane są z niskiej jakości profili i szyb o słabych parametrach izolacyjnych. Takie okna mogą z czasem odkształcać się, tracić szczelność i prowadzić do wyższych rachunków za ogrzewanie.

W GM PLAST oferujemy wysokiej klasy profile PCV, w tym energooszczędne systemy takie jak Salamander bluEvolution 82 lub Kommerling, które spełniają standardy budownictwa pasywnego.

❌ 2. Assembly bez taśm – tylko na piankę

To jeden z największych grzechów przy montażu windows. Montaż wyłącznie na pianę montażową bez zastosowania taśm paroszczelnych i paroprzepuszczalnych prowadzi do powstawania mostków termicznych, wilgoci i pleśni.

Warm installation z użyciem taśm to obecnie standard w nowoczesnym budownictwie – gwarantuje lepszą szczelność i trwałość całej konstrukcji.
W GM PLAST oferujemy profesjonalny, warm installation w standardzie, dbając o każdy detal.

❌ 3. Zamawianie windows bez wcześniejszych konsultacji

Zbyt często klienci zamawiają windows bez konsultacji z firmą montażową, co kończy się błędnymi wymiarami, niewłaściwym otwieraniem czy niepasującymi elementami. To generuje dodatkowe koszty i nerwy.

W naszej firmie zawsze przed montażem wysyłamy montażystów, którzy dokonują dokładnych pomiarów i weryfikują szczegóły – tak, by wszystko pasowało idealnie.

❌ 4. Pomijanie roller shutters i mosquito nets na etapie zamówienia

Wielu inwestorów odkłada zakup roller shutters or mosquito nets „na później”. To błąd, ponieważ późniejsze dopasowanie ich do już zamontowanych windows może być trudniejsze i droższe.

W GM PLAST oferujemy kompleksowe rozwiązania: rolety external, nadstawne, concealed and mosquito nets, które idealnie współgrają z naszą stolarką okienną.

❌ 5. Zły dobór colour – moda zamiast praktyczności

Czarne okna wyglądają nowocześnie, ale nie wszędzie się sprawdzą – szczególnie od strony południowej, gdzie mogą się mocno nagrzewać. Z kolei białe łatwiej się brudzą. Warto dobrze przemyśleć wybór koloru, nie tylko pod kątem estetyki, ale i praktyczności.

W naszej ofercie znajdziesz szeroką gamę kolorów: od antracytu, przez orzech i złoty dąb, aż po nowoczesne warianty jak Vintage Oak czy Nebraska.

✅ Podsumowanie

Selection windows to nie tylko kwestia gustu – to również decyzja, która wpływa na komfort, koszty utrzymania domu i trwałość całej inwestycji. Unikając powyższych błędów, zyskujesz spokój na lata.

Szukasz profesjonalnej firmy, która pomoże Ci dobrać i zamontować odpowiednie okna? Skontaktuj się z nami – przygotujemy darmową wycenę i doradzimy najlepsze rozwiązanie.

What is the heat transfer coefficient windows (Uw)?

The heat transmission coefficient, denoted by the symbol Uwis one of the most important technical parameters to be taken into account when selecting the windows. It defines, how much heat escapes throughout window per square metre of surface area with a temperature difference of 1 degree Kelvin (K). Im lower Uw coefficient, including improved thermal insulation windowsand therefore - less heat loss and lower heating bills.

It is worth knowing that Uw is the total value, which includes both the frame and the insulating glass unit. It consists of two other parameters:

• Uf - the thermal transmittance of the window frame. frame),

• Ug - the thermal transmittance of the glazing. glass).

To calculate Uw accurately, the following is taken into account percentage of individual elements windows, their surface and their thermal conductivity. This is why even the best glazing will not guarantee a low Uw if a poor quality frame profile is used.

Examples of Uw values and what they mean in practice:

By comparison: contemporary requirements for new buildings in Poland (as at 2025) specify that Uw must not be higher than 0.9 W/m²K. For passive houses, the recommended value is 0.6-0.8 W/m²K.

In practice, this means that by choosing windows with a low Uw coefficient, we not only invest in thermal comfortbut above all in long-term savings. Heat loss through partitions, including through leaky windowsmay be responsible for even 25-30% of the total heating energy demand.

Why is Uw factor crucial in 2025?

In 2025, the topic of energy efficiency windows is becoming even more important than ever. Rising energy prices, climate change, new building regulations and greater environmental awareness are making low heat transfer coefficient Uw is becoming not so much an option as a necessity for investors and homeowners.

Reduced heating bills

The simplest and most noticeable effect of low Uw is real financial savings. Windows with a high U-value can "drain" hundreds of kWh of energy from a building every year. The lower the Uw, the lower the heat loss and thus the lower heating costs, by up to 20-30% per year. At a time when gas and electricity prices are unpredictable, this makes a huge difference to the household budget.

Year-round thermal comfort

Good windows not only lower bills, but also higher quality of life. Windows with low Uw effectively retain heat in winter, but also protect against overheating in summerespecially if they are fitted with solar control coatings. This ensures that the temperature in the home remains stable and that householders do not have to agonise over the chill at the window in winter or the stifling heat in summer.

Energy-efficient and passive construction - a standard, not a luxury

There is no longer any place for outdated solutions in modern construction. Energy-efficient and passive houses is the future of the real estate market. In order to obtain the relevant certificates or subsidies (e.g. from the Clean Air Programme), investors have to choose windows with very low Uw - usually below 0.9 W/m²Kand in passive houses even less than 0.8 W/m²K.

Thanks to modern production technologies - such as those used by the GM PLAST - Achieving such performance is entirely possible, without compromising on aesthetics or durability.

New regulations in 2025 - what has changed?

In accordance with the current Technical Conditions in force from 2021 and tightened in 2025, all newly constructed buildings must be nearly zero-energy buildings (nZEB). This means not only modern heating systems, but also windows with very good thermal performance.

From 2025, in practice:

• Maximum Uw coefficient for façade windows must not exceed 0.9 W/m²K,

• For roof windows, the limit is 1.1 W/m²K,

• More and more banks and institutions are making the granting of a green loan conditional on the use of energy-efficient windows.

In a nutshell. if you want to build legally and in line with trends, you need to bet on windows with low Uw.

Which Uw values are considered good and which are considered excellent?

Choosing new windows, it is worth paying particular attention to the Uw heat transfer coefficient, as this largely determines the energy efficiency of a building. But what values are considered goodwhich can be described as excellent?

Below is a practical table of the most commonly used Uw thresholds:

Uw recommendations for different building types:

🔹 Residential block (thermal modernisation):
If you mention windows in a large-panel block of flats, the recommended Uw value is approximately 1.0 W/m²K. In such buildings there is often no need for the most expensive windows passive, but it is worthwhile to ensure that the insulation is clearly improved over the old wooden windows.

🔹 Single-family house (modern construction):
In the case of house construction, it is worth choosing windows o Uw less than 0.9 W/m²K. This will ensure thermal comfort, lower heating costs and compliance with current standards. In houses with recuperation and heat pumps, windows will work best with Uw 0.7-0.8 W/m²K.

🔹 Office or commercial premises:
Commercial buildings are increasingly using energy-efficient windows. For a good energy balance and savings on heating, we recommend the values of less than 1.0 W/m²K, especially if the facility has air conditioning and zoned heating systems.

🔹 Passive / zero-energy house:
There are no compromises here. In order to meet the stringent passive house standards, it is necessary to windows with Uw ≤ 0.8 W/m²Kand preferably 0.6-0.7 W/m²K. Only such parameters allow the building's thermal energy requirements to be zero.

What factors influence the heat transfer coefficient?

The Uw value is influenced by many elements - not only by the glassbut also the profile of the frame, the type of materials used and even the method of installation. It is worthwhile to understand each of these factors, as together they form a coherent insulation systemwhich determines the comfort and energy efficiency of the entire windows.

1. window profile type - PVC, aluminium, wood

• PVC (plastic) - is currently best price/thermal performance ratio. PVC profiles with multi-chamber construction and thermal inserts achieve very low Uf (up to 0.92 W/m²K). Our systems are an example Kömmerling and economical Decco series.

• Wood - natural material with good insulating properties, but requires more frequent maintenance. Uw can be very good, but at the expense of thicker frames.

• Aluminium - aesthetically pleasing, durable, great for large glazing, but without thermal breaks have a high Uf. Modern systems with thermal insulation (e.g. with a polyamide spacer) significantly improve this parameter.

2. type glazing - 2-glazed vs 3-glazed, low-e coatings

• Package 2-pane - most common in older windows. Ug approx. 1.1-1.3 W/m²K - does not meet current standards.

• Package 3-pane (triple-glazed) - used in modern windows, often with noble gas (argon, krypton). Ug even 0.5-0.6 W/m²K.

• Low-E coatings - special layers that reflect heat into the building. Significantly improve glazing insulation without changing the thickness of the glass.

3. Warm frame spacer

It's glazing separator in an insulating glass unit, often underestimated but with a real impact on the final Uw.

• Traditional aluminium frames conduct the cold, leading to the formation of thermal bridges.

• Warm frames (e.g. stainless steel, plastic or composite) reduce heat loss along the edge of the glass, improving Uw by up to 0.1-0.2 W/m²Kand also eliminate the risk of windshield dew.

4 Method installation - traditional vs. warm fitting

Even the best windows lose their properties if they are badly fitted.

• Traditional assembly (for mounting foam and anchors) is the minimum today, which in many cases does not ensure full tightness.

• Warm installation with vapour-proof and vapour-permeable strips (so-called layering) eliminates thermal bridges between the frame and the wall, significantly reduces heat and moisture loss.
  At GM PLAST we use both standard and warm installation - always advising the customer on the best solution for the building.

  How to lower the Uw coefficient when buying new windows?

  When buying new windowsMany investors focus on the appearance, price or completion date. Meanwhile a key technical parameter which has a real impact on thermal comfort and heating bills is precisely the heat transfer coefficient Uw. So how do you approach the purchase wisely to choose windows with the lowest possible Uw?

  1. Choose the right window system

  Not all windows are created equal. Which profile system and glazing package you choose, has the greatest impact on the final Uw value.

  • For customers who value energy efficiency and modern design, we recommend systems Kömmerling - are premium windows that, in triple-glazed variants with warm frames, reach up to Uw of 0.7 W/m²K.

  • For those looking for a reasonable compromise between price and qualityprofiles are the ideal choice Decco - robust, aesthetically pleasing and attractively priced, with Uw within 0.9-1.0 W/m²K.

  2. trust in professional advice and installation

  Parameters windows is one thing - but only professional selection and installation guarantees that the low Uw will also be maintained under actual conditions.
  At GM PLAST we always offer technical support in selecting the glazing package, frame and installation method.
  We advise on whether, for a given building, a better passive windowWhether they are energy-efficient, which installation method works best and whether it is worthwhile to use, for example, an energy-saving system. warm frame or sunscreen coating.

  3. Don't skimp on quality - it doesn't pay off

  Purchase of the cheapest windows with poor performance is an apparent saving.

  • Such windows have high Uw (1.3 W/m²K and above)which translates into greater heat loss and higher bills for years to come.

  • In addition, they wear out faster, have inferior seals and are less weather-resistant.

  Instead, it is better to invest once - in tested profiles, triple-glazed packages, warm frames and professional installation. The difference in price can pay for itself after just a few heating seasons. In the long term, you save energy, money and... nerves.

  Summary - what to keep in mind when choosing windows with good Uw

  Selection windows with a low Uw heat transfer coefficient is the key to comfort and economy in any building. Here is Top 5 things to keep in mind when buying windows:

  • Choose windows with certified low Uf profiles - PVC, wood or aluminium with thermal breaks.

  • Opt for modern glazing packages - preferably triple-glazed with low emissivity coatings and warm spacer.

  • Pay attention to professional installation - preferably so-called warm installation eliminating thermal bridges and ensuring airtightness.

  • Don't skimp on quality - good windows are an investment that pays off over the years thanks to lower heating bills.

  • Benefit from expert advice and service - choose a proven manufacturer and contractor who can help you choose the optimal solution.

  ---

  If you're looking for windows that combine high quality, state-of-the-art technology and value for money - then you're in for a treat. Contact GM PLAST!
  Our experienced team will be happy to advise you on the best solutions and help you order windows tailored to your needs. Together, we will ensure the warmth and comfort of your home or office.

The most common mistakes in window installation and how to avoid them

Installation of windows is one of the most important stages of any construction or renovation project. Even the best windows - with excellent thermal, acoustic and aesthetically pleasing properties - will not do the job if they are incorrectly installed. Unfortunately, many builders still treat installation as a secondary issue, focusing mainly on the choice of the product itself. Meanwhile, it is quality installation determines whether windows will be airtight, durable and energy-efficient.

Incorrect installation leads to serious problems such as heat loss, blowing out, damp walls, mould or even damage to joinery. As a consequence, this can generate high repair costs, increase heating bills and reduce the living comfort of the occupants. Instead of saving money, the builder exposes himself to additional expenses that could easily be avoided in many cases.

At GM PLAST we have for years paid particular attention not only to the quality of the offered windowsbut also on professional and precise installation. Our fitters are experienced specialists who are well versed in both traditional techniques and modern solutions, such as warm installation with sealing tapes. This ensures that we our realisations meet all standards and customer expectations - both in Poland and abroad.

In the following section, we will outline the most common mistakes made with the window installationThe effects of these and how to avoid them. If you are planning a replacement or installation of new windows, be sure to read this guide to the end - it will not only save you time and nerves, but also money.

The most common errors in window installation

Installation of windows is a process that requires precision, experience and knowledge of modern technology. Unfortunately, many teams make mistakes that can lead to problems such as leaks, damp walls or even deformed joinery. Below we present the most common errors in window installation, their effects and how to avoid them.

1. Failure to adequately prepare the window opening

🔴 Error:
It is often the case that windows are installed in inadequately prepared openings, which may be uneven, dirty or damp. Dirt, old mortar or unevenness can hinder the proper seating of the frame and affect airtightness.

⚠ Implications:

• Difficult to level correctly windows

• Poor adhesion of the installation foam

• Possibility of settlement windows after installation

✅ How can this be avoided?
Before installation of The opening should be cleaned and levelled, any loose plaster removed and its moisture content checked. If necessary, it is a good idea to reinforce the edges of the opening with special profiles or levelling mortar.

2. inadequate sizing windows into the hole

🔴 Error:
Too small or too large windows in relation to the opening cause problems with their correct installation. It is often the case that builders order the windows "on contact", which makes it impossible to make expansion joints properly.

⚠ Implications:

• Excessive stresses in the window frame, which can lead to cracks

• Problems with proper sealing

• Possibility of thermal bridges

✅ How can this be avoided?
Window should be 10-20 mm smaller than the mounting hole to ensure that the installation clearancewhich allows for proper sealing and compensation for material expansion.

3. incorrect levelling and alignment windows

🔴 Error:
Window must be perfectly level and at right angles to the wall. A common mistake is to install 'by eye' or to use the wrong spacer wedges.

⚠ Implications:

• Difficulty opening and closing sashes

• Excessive stresses in the hinges leading to faster wear and tear of the hardware

• Sashes falling out of the frame in extreme cases

✅ How can this be avoided?
To set windows a spirit level and installation wedges should be used. After initial seating, it is necessary to check the plumb and level on several planes.

4. improper attachment of window frame

🔴 Error:
Inappropriate placement of anchors or dowels, or too few of them, can weaken the structure windows.

⚠ Implications:

• Window can deform under weight and stress

• Leakage weakening, formation of leaks

• Risk of window damage in high winds or draughts

✅ How can this be avoided?
Fixing should be done according to the guidelines window manufacturer. Recommended anchor arrangement:

• In corners - max. 15 cm from the edge

• Every 50-70 cm along the frame

5. inadequate sealing with installation foam

🔴 Error:
Too much or too little polyurethane foam can impair airtightness windows. It is often used the foam itselfwithout additional sealing tapes, which is a mistake.

⚠ Implications:

• Poor thermal insulation - heat loss

• Moisture absorption by the foam, which can lead to damp walls

• Possibility of frame deformation

✅ How can this be avoided?
Use polyurethane foam in the correct amount and vapour-proof and vapour-permeable stripswhich protect the insulation from moisture.

6. Lack of vapour-proof and vapour-permeable tapes (with warm installation)

🔴 Error:
Traditional installation on the foam itself does not provide adequate protection against moisture. The lack of taping causes the foam to soak up water, leading to degradation.

⚠ Implications:

• Increased heat loss

• Risk of mould and mildew growth in the insulation layer

• Faster loss of foam insulation properties

✅ How can this be avoided?
It is worth betting on warm installation, which involves the use of:

• Vapour-permeable strips (external side) - wicks moisture to the outside

• Vapour barrier tape (on the inside) - prevents moisture penetration into the insulation

💡 At GM PLAST we use warm installation as standard, so that our customers can enjoy the highest energy efficiency windows.

7. No expansion joints or space for thermal expansion

🔴 Error:
Building materials, including PVC i aluminiumThey change their dimensions under the influence of temperature. If window is fitted "in compression", deformation may occur.

⚠ Implications:

• Crackling and creaking of the frame

• Problems with opening and closing sashes

• Cracks in glass or profiles in extreme cases

✅ How can this be avoided?
Keep Adequate installation play as mentioned above especially with PVC windows (10-20 mm) and use flexible seals.

Warm installation - a way to avoid mistakes and improve energy efficiency

More and more investors and homeowners are opting for warm installation windowsinstallation method window joinerywhich ensures not only a solid seat, but above all excellent air-tightness and high thermal insulating capacity. In times of rising heating costs, this solution is becoming not only cost-effective, but essential.

What is the difference between warm installation than the traditional one?

🔹 Traditional installation consists mainly of fixing the window mechanically (with anchors or dowels) and sealing the installation space. exclusively with polyurethane foam. Unfortunately, this foam - although it has good insulating properties - is very sensitive to moisture and does not sufficiently protect against moisture penetration.

🔹 Warm installation is a modern technique that involves the execution of a so-called 'fusion'. three-layer sealing:

• inner layer - vapour-proof tapewhich prevents the penetration of water vapour from inside the building into the insulation layer,

• middle layer - installation foam as thermal and acoustic insulation,

• outer layer - vapour-permeable tape, which protects the insulation from precipitation and UV radiation while allowing moisture to evaporate to the outside.

💡 In practice, this means that warm installation protects against wall moisture, heat loss and mould growthwhich is of great importance for the sustainability of windows and the comfort of residents.

Advantages of using tapes - protection against moisture and heat loss

✅ Increased tightness of the window-wall connection - The tapes eliminate the risk of thermal bridges and uncontrolled air flow.
✅ Longevity of the insulation layer - polyurethane foam does not degrade as it is protected from moisture and UV radiation.
✅ Protection of the wall structure - moisture does not penetrate the masonry, reducing the risk of dampness and mould growth.
✅ Improved sound insulation - The three-layer seal increases protection against noise from outside.
✅ Higher energy efficiency of the building - thanks to airtight window installation heating energy requirements can be significantly reduced.

Reducing heating bills through airtightness

High air-tightness achieved through warm installation translates directly into lower heating costs. In winter warm air does not escape through leaks around the windowsand in summer - the coolness from the air conditioning does not escape.

According to the research, properly executed warm installation can reduce heat loss through window joints by up to 70%which may translate into savings of several hundred PLN per year in an average single-family home.

In addition, airtight installation supports meeting the requirements of WT 2021 (technical conditions of buildings), which is important for building approvals and obtaining subsidies, e.g. from programmes "Clean Air".

why choose GM PLAST?

At GM PLAST we offer professional warm installation as standard - tapes, foams, anchors, all in accordance with the latest standards. We do not regard this solution as an "extra option" - for us it is the basis for modern, energy-efficient construction.

Thanks to many years of experience, modern technical facilities and cooperation with renowned manufacturers (Kömmerling, Decco, Aluplast, Salamander, Aluprof, Aliplast, Reynaers), we are able to offer our clients:

• expert technical advice,

• precise and tight assembly in compliance with current regulations,

• comprehensive service - from measurement to service,

• products that meet the highest standards of thermal and acoustic insulation.

👉 Bet on quality that translates into real savings - choose warm installation with GM PLAST.

The importance of the experience of the installation team

Correct window installation It's not just a question of choosing the right materials and technology - the the experience and knowledge of the installation team play a key role here. Even the highest quality windows will not fulfil their function if they are poorly seated, inaccurately sealed or not installed in accordance with the manufacturer's recommendations.

Why rely on certified and experienced professionals?

🔧 Professionals know the current installation standards and building regulationsso they can avoid many of the problems associated with misplaced joinery.
🔧 Experienced fitters can choose the right technique for the type of wall and the specific building - mounted differently windows in a new energy-efficient house, and differently in an old building with thick walls.
🔧 Certified teams work according to the three-layer installation technology, ensuring tightness, durability and aesthetic finish.
🔧 They know how to prepare the reveal properly, how to ensure that the frame is properly levelled, how to use tapes and foams to avoid later problems with leaks, freezing or deformation.
🔧 Professionals can also react quickly to unforeseen situations - such as unevenness in the masonry, missing right angles or other construction defects.

Errors are most often due to saving on the team

One of the most common reasons for errors in window installation is attempt to save on labour. Choosing the cheapest team or installing it yourself without experience can lead to:

• leaks around the window frame,

• the formation of thermal bridges,

• damp masonry and mould growth,

• cracking of the plaster and deformation of the frame,

• or even to complete disassembly and the need for reassemblywhich generates high additional costs.

💸 Paradoxically - saving a few hundred zloty in the beginning often means Several thousand PLN of losses in the long termnot to mention the loss of thermal comfort or interior aesthetics.

 GM PLAST are professionals you can trust

Our installation teams undergo regular training and are familiar with the characteristics of both modern and older buildings. This allows us to perfectly match the technique installation to the technical conditions of the facility in question.

By cooperating with GM PLAST, you gain:

• access to a trained assembly team,

• the certainty that installation will be carried out in accordance with standards and manufacturers' recommendations,

• guarantee of durability and tightness of installation,

• as well as professional technical advice at every stage of the investment.

Don't take risks - trust the proven specialists and choose a comprehensive service window installation with GM PLAST.

How to avoid mistakes? A step-by-step guide for the investor

Installation of windows is one of the most important stages during the construction or modernisation of a house. Not only does the durability of the joinery depend on its quality, but also thermal comfort, noise levels inside the building and the amount of heating bills. Here is tipswhich will help you avoid the most common mistakes and ensure the longevity of your investment.

1. Choose a proven company with experience

Bet on a partner who doesn't just sell windowsbut also deals with their professional installation of. At GM PLAST we offer a comprehensive service - from technical advice to professional installation carried out by trained teams.
Don't just go for the price - experience, good reviews and references are just as important as an attractive offer.

2. ask for warm installation and a written guarantee

Warm installation using vapour-proof and vapour-permeable tapes, polyurethane foam and suitable anchors is the standard in modern construction today.
Ask the contractor for details of the technology and ask for a written guarantee on the work carried out - is an additional safeguard for you as an investor.
W GM PLAST all assemblies are carried out in accordance with warm installation, ensuring airtight and energy-efficient construction.

3. Ensure proper preparation of the walls

Many mistakes result from an unprepared reveal - crumbling, damp or with unevenness. Before installation you should:

• Remove loose plaster fragments and level the surface,

• ensure that the substrate is dry and stable,

• use a suitable primer or levelling layer.
  Particularly when it comes to the thermal modernisation of buildings, it is worth consulting a professionalto prepare window openings in accordance with current technical requirements.

4. Check technical documentation and ask for acceptance after installation

Don't be afraid to ask for details - any serious company should provide you with an installation project, indicate the materials and technology used.
After completion of the work, be sure to carry out technical acceptance, preferably with a company representative. Check:

• tightness of joints,

• the workmanship of the window sills,

• operation of fittings and handles,

• cleanliness and aesthetics of workmanship.
  W GM PLAST we carry out final inspections and discuss all relevant aspects of the installation with the customer.

5. make sure the team uses certified materials

Sealing tapes, mounting foams, anchors and screws - all of these items should have certificates and approvals proving their durability and compliance with the standards.
Our teams use only proven assembly systemsthat achieve the highest levels of airtightness and thermal insulation.

Summary - investment in good windows This is only the beginning. Equally important is their professional installation. If you want to avoid mistakes, rely on experience, modern technology and full documentation.

Why choose windows from GM PLAST?

Choosing windows is a decision that will last for years - so it is worth betting on a proven manufacturer that combines quality, experience and a comprehensive service. GM PLAST is a company that for more than 25 years has not only provided its customers with durable and aesthetically pleasing windowsbut also full support at every stage of the investment. Here's what sets us apart:

✅ Top-quality PVC profile windows Kömmerling

In our offer you will find energy-efficient and durable window systemsbased on renowned German profiles Kömmerling. With these, your windows will last for many years, providing excellent thermal and acoustic insulation.

✅ Professional installation - in Poland and abroad

We are not only active locally - we implement assemblies throughout Poland and also abroad, mainly in Belgium and France. We offer both traditional assemblyas well as warm assembly¿ as standard, using modern tapes, foams and anchors that meet the latest building standards.

✅ Comprehensive customer service

From the first contact to the completion of the installation, we are at your service. We provide:

• expert technical advice,

• precise measurements,

• transport to the indicated address,

• and installation by experienced teams.

With us, everything runs smoothly and without stress.

✅ 25+ years of experience and modern machinery

We are one of the largest PVC joinery manufacturers on the profile Kömmerling in the region. Our production line is based on modern technologiesand every stage of implementation is carefully monitored. Hundreds of satisfied customers are our best calling card.

✅ Windows to suit all budgets

We understand the needs of different customers - that is why our offer includes both economic solutions (e.g. on Decco profiles)as well as premium products. We help select the best solutions for each budget and investor's needs.

Don't risk cooperating with accidental teams - bet on quality, which has already been appreciated by many customers in Poland and Europe. Choose GM PLAST - with us you gain peace of mind, safety and the certainty of an excellent result.

Window installation is key stagewhich has a direct impact on the comfort, safety and energy efficiency of your home. Unfortunately, many people make a serious mistake, looking for savings at this very stage. Improperly seated windows can lead to leaks, thermal bridges, damp walls and even the need for costly joinery replacement - often after only a few years.

That is why it is worth betting on a proven partner that knows what it is doing. At GM PLAST, we have been combining for over two decades premium PVC windows z professional, certified installation. Our experience, state-of-the-art technology and individual approach make us the trusted choice for hundreds of customers in Poland, Belgium and France.

🔧 Don't take risks - go for proven quality.
📐 Request a free quote or contact us, and we will advise you on the best solution to suit your budget and expectations.

Your home deserves the best

What is window treatment?

Warm sill - what is it and is it worth it?

Warm sill is an innovative solution used during window installationwhich increases their thermal insulation and improves the tightness of the frame-to-masonry connection. It is a special profile usually made of extruded polystyrene (XPS) or polyurethane (PUR) foamwhich is mounted under window as an insulating layer. This effectively eliminates thermal bridges, reducing heat loss and limiting the risk of damp walls around the windows.

How the warm sill?

A warm window sill has several key functions:

• Provides better thermal insulation - reduces heat loss, resulting in lower heating bills.
• Seals the joint windows with a wall - eliminates leaks through which cold air could penetrate.
• Facilitates assembly windows - provides a stable and level base, so that the window is precisely embedded.
• Protects against moisture - reduces the risk of condensation and mould growth.

A warm window sill is a particularly good solution for modern energy-efficient construction and passive houses.

Warm sill

How much does a warm sill?

The cost of warm sill depends on several factors, such as material type, profile thickness and width windows. Average prices fluctuate in the following ranges:

• Standard warm sill XPS - approx. PLN 30-60 per running metre.
• Warm sill of PUR foam - approx. PLN 50-100 per running metre (a more expensive but more sustainable option).
• Warm sill dedicated to energy-efficient windows - PLN 100-150 per running metre.

To this must be added the installation costs, which can range from PLN 20 to 50 per metredepending on the region and contractor.

Is it worth investing in a warm sill?

Definitely yes! Warm sill is an investment that pays off in the form of lower heating costs, greater thermal comfort and longer service life windows. This is particularly important in modern construction, where energy efficiency and structural integrity count.

If you are planning to replace windows or building a new home, it is worth considering installing a warm window sill as an additional layer of insulation to provide better protection against the cold and damp.

When to use warm sill?

Warm sill is a solution that proves its worth in many cases, especially when it comes to improving the thermal insulation of a building. Here are situations where its use is particularly beneficial:

• In new energy-efficient and passive construction -. If you are building a modern home with high insulation performance, warm sill is almost a necessity. Provides better sealing windowsreduces heat loss and helps meet standards energy-efficient and passive constructionwhere the aim is to minimise energy consumption.

• When replacing windows in an older building - If you plan to replace windows in an older house, it is worth thinking about a warm windowsill. Old buildings often have thermal bridgesthrough which heat escapes, leading to higher heating bills and moisture problems. Warm sill will help to prevent this, especially if we install modern, energy-efficient windows.

•  When you want to eliminate thermal bridges - Thermal bridges are places in the building envelope through which heat escapes to the outside. Warm sill eliminates this problem, improving thermal comfort in the room and protecting against moisture. This is particularly important in rooms exposed to temperature differencessuch as the kitchen or bathroom.

• In areas with harsh climates - If you live in a region where winters are harsh, warm sill will provide better insulation and greater thermal comfort at home. It will also prevent the phenomenon of frosting windowswhich can lead to condensation and mould on the walls.

• When you want to avoid condensation at the joint windows and wall - Many people are struggling with evaporation of glazing and dampness around the windowsespecially during the heating season. This is the result of the temperature difference between the inside and outside of the building. Warm sill improves insulation and reduces this phenomenon, thus avoiding problems with damp and mould.

•  If you plan to install large, heavy windows – In the case of large glazings, for example terrace doors or panoramic windows, warm windowsill stabilises the structureprevents deformation and improves joint strength windows with the wall. This is particularly important

Frequently asked questions:

1. whether warm windowsill is it necessary?

Not mandatory, but significantly improves thermal insulation and joint tightness windows with masonry. It is particularly recommended for energy-efficient and passive houses.

2. whether warm windowsill Suitable for all types of windows?

Yes, it can be used both under PVC windows, woodenas well as aluminium. It is available in various variants to suit systems windows.

3. whether it is possible to install warm windowsill in an existing building?

Yes, but this is best done during exchanges windows. In an existing building, installation may require additional building work.

4. What materials are used in the production of warm window sills?

The most common use is extruded polystyrene (XPS) or polyurethane (PUR) foamwhich have high thermal insulation properties.

5. how the assembly goes a warm windowsill?

It is installed prior to embedding windows. Assembly consists of gluing and sealing the profile on the substrate and then set the frame on it windows.

6. whether warm windowsill affects the installation of the external and internal sills?

Yes, it facilitates the installation of window sills, providing better support and tightness of connections.

7. how much does it cost to install a warm windowsill?

The price depends on the contractor, but is usually PLN 20-50 per running metredepending on the complexity of the work.

8. whether warm windowsillt can be used for large glazings?

Yes, especially in the case of sliding systems (HS, PSK)where stability and insulation of the lower part of the structure are crucial.

9. whether warm windowsill prevents freezing windows?

Yes, it eliminates thermal bridgeswhich are the main cause of frostbite at the interface windows and masonry.

10. What are the differences between a warm windowsill and a standard foundation for window?

Standard underlay often does not provide such good insulation and airtightness, whereas warm windowsill significantly reduces heat loss and improves stability windows.

What do I clean my windows with to get them perfectly clean?

Clean windows are the showpiece of any home or flat. However, in order to avoid streaks, smudges and deposits, it is worth knowing what is the best way to clean them. The right choice of cleaning agents and cleaning technique will allow you to enjoy perfectly clear windows without unnecessary effort.

Home remedies for window cleaning

Many people are satisfied with simple, homemade ways of cleaning their windows. The most popular solution is a 1:1 solution of water and vinegar. Vinegar effectively removes dirt, leaves no streaks and gives the windows a shine. Another way is to use warm water with lemon juice, which has similar cleaning properties and leaves a pleasant fragrance. Some people also use water with glycerine, which prevents dust and rain from quickly settling on the windows.

Ready-to-use window cleaning products

There are many professional window cleaners available on the market. It is advisable to choose those that do not contain ammonia, as this can damage the surface of the glass and affect health. Popular cleaning products contain isopropyl alcohol, which evaporates quickly without leaving streaks. If you want an environmentally friendly solution, you can reach for biodegradable glass cleaners that do not contain harmful chemicals.

Which window cleaning tools to choose?

In addition to the right cleaning products, the choice of window cleaning tools is important. The best options are:

• Microfibre - Absorbs water perfectly and leaves no streaks.
• Chamois leather cloths - a natural material that gently cleans windows.
• Rubber squeegees - reliable in removing water and dirt without leaving any streaks.
• Window steamer - effectively removes dirt without the need for detergents.

Window cleaning

How to clean windows properly?

For best results, it is worth following a few rules:

1. Wash windows on a cloudy day - the sun's rays cause liquids to dry quickly, which encourages streaks.
2. Start with the window frames - removing dust and dirt from the profiles will prevent them from being transferred to the glass.
3. Use two cloths - one for cleaning and one for polishing.
4. Wash the glass with vertical movements on one side and horizontal movements on the other - this will allow you to spot any streaks more quickly.
5. Don't forget the seals and fittings - their regular maintenance extends the life of your windows.

Summary

Clean windows not only mean better aesthetics, but also more natural light in the rooms. Regular window cleaning, the right choice of cleaning agents and tools will allow you to enjoy spotlessly clean windows without streaks and stains. By choosing effective, yet safe cleaning methods, you can make this task much easier and achieve a long-lasting effect of shiny windows.