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Cost calculator for new windows in old buildings
Wondering what new windows really cost for your old building? The answer is more complex than a simple price per window, as materials, installation, and subsidies significantly affect the final sum. Discover how a strategic approach not only saves costs but also sustainably increases the value of your property.
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The total cost for new windows in an old building often ranges between €7,500 and €15,000, depending on material, glazing, and installation effort.
Government subsidies (BAFA/KfW) can reduce the investment by up to 20%, which corresponds to a maximum saving of €12,000.
Modern windows with triple glazing can reduce heating costs by up to 15% annually and sustainably increase property value.
The replacement of windows in an old building is one of the most effective measures to increase energy efficiency and property value. However, many owners are deterred by the unclear costs. A simple cost calculator for new windows in old buildings provides initial estimates, but the true optimisation lies in the details. This article breaks down the key cost factors from materials to installation, shows you how to take advantage of government grants of up to €12,000, and how the investment pays off through reduced heating costs of up to 15% annually. This way, you can make an informed decision that pays off in the long term.
The total cost of new windows consists of three main components: material, glazing, and installation. A standard plastic window is available from around €400, while wood-aluminium windows can cost up to €1,000 each. The removal and disposal of old windows can add an extra €50 to €100 per unit. For a typical single-family house with 10 windows, you should budget between €7,500 and €15,000 in total. The complexity of installation in an old building can increase these costs by 10-20%. Therefore, a precise calculation is essential to avoid financial surprises. Choosing the right material and glazing not only affects the price but also the future energy performance of your property.
The choice of material is a crucial factor for both cost and aesthetics. Plastic windows are the most affordable option, with prices starting from €400, and they score points for low maintenance. Wooden windows offer a warm appearance and good insulation values, but they can quickly cost 20-30% more. High-quality triple glazing is now standard and a prerequisite for most funding programs. It significantly improves the thermal transmittance (U-value). Modern windows achieve a U-value of up to 0.5 W/(m²K), while old windows often have values over 2.0 W/(m²K). Double glazing is only advisable in an energy-inefficient, unrenovated old building to prevent mould formation on walls. The investment in better glazing often pays off within a few years through lower heating costs.
Professional installation is crucial for the tightness and functionality of new windows, making up a significant portion of the total costs. You should expect installation costs of approximately €120 to €200 per window, carried out by two installers over a period of two to four hours. In older buildings, these costs can increase as adjustments to the masonry are often necessary. If a completely new window opening needs to be created, additional masonry work can incur costs of €1,300 to €1,700. Here, the expertise of a professional company is essential. Poor installation can lead to thermal bridges and negate any overall energy savings. Therefore, always obtain multiple quotes that transparently break down labour and material costs, as is customary with a complete renovation of an old building.
The state supports window replacement with attractive subsidy programs that significantly reduce your investment costs. The Federal Office for Economic Affairs and Export Control (BAFA) offers a grant of 15% on eligible costs up to €30,000, which corresponds to savings of up to €4,500. If the measure is part of an individual renovation roadmap (iSFP), the grant even increases to 20% of up to €60,000, or a maximum of €12,000. For this, the new windows must achieve a U-value of no more than 1.3 W/(m²K). Additionally, you can apply for a supplementary loan of up to €120,000 through the KfW Bank. Involving a certified energy efficiency expert is mandatory for applying for the BAFA subsidy. A professional subsidy check ensures that you exploit all potential benefits.
Investing in new windows pays off not only through increased living comfort but also through direct financial savings. Replacing outdated windows can reduce annual heating costs by up to 15%, which can amount to approximately €250 per year, depending on the building. Outdated windows can cause a loss of up to 40 litres of heating oil per year per square metre of window area. With an online calculator for heating cost savings, you can roughly estimate your potential savings. This energetic renovation measure sustainably increases the value of your property. The payback period depends on energy prices and any subsidies used, but it is often less than 15 years. The exact increase in the value of your property can be determined through a data-driven evaluation.
The costs for new windows in old buildings are a significant but worthwhile investment. An online calculator provides an initial guide, but detailed planning is the key to success. By cleverly combining material selection, professional installation, and taking full advantage of subsidies, you can reduce costs by up to 20%. In the long term, you benefit from lower energy costs and a significant increase in the value of your property. Before making a final decision, you should know the current market value of your property and its potential after renovation. An objective property valuation, such as the one offered by Auctoa, provides you with the necessary data basis. Chat now for free with our ImmoGPT to address initial questions. Make your decision based on facts, not just intuition.
Statistisches Bundesamt (Destatis) provides comprehensive information on construction prices and property price indices.
BKI (Baukosteninformationszentrum Deutscher Architektenkammern) offers current data and analyses on the construction price index.
KfW provides information on funding programmes for energy-efficient renovation of existing properties, especially window replacement.
energiewechsel.de (Bundesministerium für Wirtschaft und Klimaschutz) provides details on tax incentives for energy-efficient building renovations.
Statistisches Bundesamt (Destatis) offers further specific data on construction price indices as part of the economic indicators.
Statistikportal.de, the joint portal of the Federal and State Statistical Offices, provides access to a wide range of official statistics.
Verbraucherzentrale provides important advice and recommendations for deciding between window renovation and replacement.
How does an online calculator for the cost of new windows in older buildings work?
An online calculator typically asks for the number of windows, the desired material (plastic, wood, aluminium), and the type of glazing. It provides a rough estimate of the material and installation costs. However, for precise planning, a detailed quote from a specialist company that takes into account the specific conditions of your older building is essential.
What U-value should new windows have?
According to the Building Energy Act (GEG), new windows must not exceed a thermal transmittance (U-value) of 1.3 W/(m²K). Often, even better values are required for grants. Modern windows with triple glazing easily achieve values between 0.5 and 0.8 W/(m²K).
How long does it take to install new windows?
The installation of a single standard-sized window typically takes two to four hours and is carried out by two installers. Replacing all the windows in a single-family house can take between two to five days, depending on the number of windows and the complexity of the work.
Can I apply for grants for window replacement myself?
For the BAFA grant, the involvement of a certified Energy Efficiency Expert (EEE) is mandatory. This expert confirms compliance with the technical minimum requirements and assists you with the application process. As the property owner, you must submit the application yourself before awarding contracts.
Do new windows always increase the value of my property?
Yes, replacing old windows with modern, energy-efficient models is a value-enhancing modernisation measure. It improves the energy balance of the building, which is reflected in the energy performance certificate and increases attractiveness for buyers or tenants. The exact increase in value depends on the condition and overall appearance of the property and can be precisely quantified through a professional property valuation.
What should be considered with windows from Poland?
Windows manufactured in Poland can be cheaper, but you should pay close attention to quality, CE marking, and compliance with German standards (especially U-values). It is also important to have a qualified installation company in Germany that assumes warranty for the installation, as this is crucial in case of complaints.
