In Germany in 2026, the cost of replacing each window including installation varies, resulting in varying total costs for a detached house with 12 windows. BAFA supports individual measures through Federal Funding for Efficient Buildings (BEG EM) with a basic grant that can be increased by providing an individual renovation roadmap (iSFP). Eligible costs are capped per residential unit, with higher limits possible where an iSFP is available. Those who do not involve an energy efficiency expert (EEE) receive no BAFA funding, but can alternatively claim tax deductions under §35c EStG.
Technical minimum requirement for BAFA funding: Uw ≤ 0.95 W/(m²K). Triple-glazed windows generally meet this value; double glazing often does not. Although RAL-compliant warm installation is not a formal funding criterion, it significantly affects long-term performance and mould risk.
What does window replacement cost per window and for the whole project?
Price ranges in 2026 vary considerably by material and specification. The reference is a standard 150 × 120 cm double-casement window with triple glazing and standard installation.
- uPVC windows:600–1,000 € per window (materials + installation)
- Timber windows:900–1,600 € per window
- Aluminium windows:1,100–2,000 € per window
- Timber-aluminium windows:1,400–2,500 € per window
These ranges assume removal and disposal are charged separately. Many quotes list these items as lump sums or bundle them without a breakdown.
Non-standard sizes, patio doors and floor-to-ceiling units cost considerably more. A floor-to-ceiling unit measuring 220 × 240 cm alone can cost 2,500–5,000 € because structural work, lintels and reveals are more involved. Such items should be calculated separately outside the standard ranges.
Which factors determine window replacement prices?
Two quotes for the same house can differ by 40 % without either being overpriced. The reason lies in decisions made before commissioning.
Frame materialis the strongest single factor. uPVC is low-maintenance and affordable, timber needs regular painting, and aluminium is durable but expensive. Timber-aluminium combines appearance with weather resistance, but carries a substantial price premium.
Glazingdetermines funding eligibility. According to KfW, triple glazing (Ug ≈ 0.5–0.7 W/(m²K)) costs340–390 € per m² of window area, while double glazing costs 290–340 € per m². The triple-glazing premium is therefore around 10–15 %, but delivers the crucial Uw-value below 0.95 W/(m²K).
Window size and shapehave a disproportionate effect. Non-standard dimensions raise the window price by 30–80 % compared with standard sizes because mass production is not possible. Arched or trapezoidal windows cost even more.
Installation methodis often underestimated. RAL-compliant warm installation with three sealing layers costs an extra 50–100 € per linear metre compared with standard installation. For a 150 × 120 window with a perimeter of approx. 5.4 linear metres, this means an extra 100–160 € per window.
Installation complexityincreases substantially on upper floors. Scaffolding or a cherry picker adds 500–1,500 €, depending on building height and accessibility.
Reveal work, roller shutters and windowsillsare not shown in many quotes. Typical ranges: reveals 150–500 € per window, roller shutter adaptation 100–300 € each, internal/external windowsills 80–200 € each.
Professional tip: For every quote, request separate lists of material costs, installation costs, removal/disposal and ancillary work. A quote stating only a total price cannot be checked or compared with others. Also ensure the finished window's Uw-value and installation method (standard or RAL) are explicitly stated.
Which material and glazing suit your project?
Material choice is not purely a matter of taste. It simultaneously affects price, funding eligibility, maintenance and lifespan.
uPVC windows dominate the German market because they require little maintenance and easily meet BAFA's Uw requirements. Timber windows suit listed and period buildings where appearance and material character matter. Aluminium is the first choice for large formats and commercial properties, but is often excessive for private housing. Timber-aluminium combines both materials' advantages: timber inside, aluminium outside, no painting and a long lifespan.
| Material | Price (€/window, 150×120 cm) | Suitable for | Uw range (W/(m²K)) | Eligible for funding (BAFA) | Lifespan / maintenance |
|---|---|---|---|---|---|
| uPVC | 600–1.000 € | New builds, existing buildings | — | Yes (triple glazing) | 30–40 years, low-maintenance |
| Timber | 900–1.600 € | Older buildings, listed properties | — | Yes (triple glazing) | 40–60 years, painting required |
| Aluminium | 1.100–2.000 € | Large formats, new builds | — | Yes (triple glazing) | 40–50 years, low-maintenance |
| Timber-aluminium | 1.400–2.500 € | Older buildings, premium | — | Yes (triple glazing) | 50–60 years, very low-maintenance |
The profile class affects long-term durability: for dark colours, a higher profile class (e.g. class A) is recommended, as otherwise the material expands more and seals wear faster.
What does installation really cost, and which items are often missing from quotes?
Installation costs are the most common hidden price driver in window replacement. Many quotes state a total price that either excludes removal and reveal work or only includes them as a lump sum.
- Removal and disposal:20–150 € per window, depending on complexity and provider; often quoted as a lump sum
- Reveal work(plastering, insulation, lining): 150–500 € per window
- Roller shutter adaptation or replacement:100–300 € each
- Internal/external windowsills:80–200 € each per window
- Scaffolding or cherry picker:500–1,500 € for the whole project, one-off
- Additional reveal insulation:50–150 € per window in older building refurbishment
The difference between standard installation and RAL warm installation is more than the premium. Standard installation inserts the window and seals it with expanding foam. RAL-compliant warm installation uses three sealing layers: airtight inside, resistant to driving rain in the middle and vapour-permeable outside. This prevents thermal bridges at the reveal and significantly reduces mould risk. Skipping RAL installation risks long-term mould damage costs that quickly exceed the 100–160 € premium per window.
Professional tip: Check whether the quote explicitly specifies "Warm installation to RAL". Without this statement, standard installation is generally intended. Ask before signing.
Example calculations: one window, four windows, ten windows
Three specific scenarios show how decisions affect the budget.
Example 1: single uPVC window, triple glazing, standard installation
| Item | Cost |
|---|---|
| uPVC window 150×120 cm, triple-glazed | 550 € |
| Standard installation | 150 € |
| Removal and disposal | 80 € |
Example 2: four windows with RAL installation and reveal work
- Four uPVC windows 150×120 cm, triple glazing: 4 × 550 € = 2,200 €
- RAL-compliant warm installation: 4 × 280 € = 1,120 €
- Removal and disposal: 4 × 80 € = 320 €
- Reveal work (older building, complex): 4 × 350 € = 1,400 €
- Internal/external windowsills: 4 × 160 € = 640 €
- Scaffolding (one-off): 600 €
Total cost: approx. 6,280 €
With an 8 % volume discount on materials, this falls to around 5,900 €. If you are also planningfaçade insulation, the scaffolding can be shared, saving a second setup.
Example 3: ten-window project with iSFP funding
- Ten timber windows 150×120 cm, triple glazing: 10 × 1,100 € = 11,000 €
- RAL installation: 10 × 280 € = 2,800 €
- Removal and disposal: 10 × 80 € = 800 €
- Reveal work: 10 × 300 € = 3,000 €
- Scaffolding: 900 €
- Energy adviser (EEE): 1,200 €
Gross cost: 19,700 €
With iSFP bonus: 20 % BAFA funding on 19,700 € = 3,940 € grant. Net investment after funding: approx. 15,760 €. Energy adviser costs qualify for 50 % funding and reduce the calculation basis accordingly.
What funding and tax options are available in 2026?
Government support for window replacement follows three routes: BAFA grant, KfW loan and tax deductions. Combining BAFA and §35c EStG for the same measure is excluded.
BAFA BEG EM: grant for individual measures
TheBAFA funding for windowsprovides basic funding of 15 % of eligible costs. With an iSFP, this rises to 20 %. Eligible cost items include windows, installation, removal/disposal, reveal work and 50 % of energy adviser costs. Limits: 30,000 € without an iSFP, 60,000 € with an iSFP per residential unit. Minimum investment is 300 € including VAT.
Important:The BAFA application must be submitted before awarding the contract. Commissioning first and applying afterwards forfeits eligibility.
KfW: supplementary loan and Efficiency House programme
The KfW supplementary loan (programme 358/359) complements the BAFA grant with a low-interest loan up to a specified limit per residential unit, with variable terms. It finances the remaining owner's contribution rather than replacing the grant. Anyone planning a complete refurbishment to an Efficiency House can obtain loans up to 150,000 € with repayment subsidies of 5–25 % through KfW programme 261. For window replacement alone, the Efficiency House programme is generally not the right route.
Tax routes: §35c and §35a EStG
The crucial difference: §35c does not require an EEE but does require a specialist contractor's certificate using the official template. §35a is simpler to apply for but limited to labour costs, making it less attractive for larger projects. Combining a BAFA grant and §35c for the same measure is expressly excluded under§35c EStG.
Step-by-step BAFA funding process:
- Commission an energy adviser (EEE) and have an iSFP prepared
- Apply to BAFA online (before awarding the contract)
- Obtain quotes and have them reviewed
- Award the contract (only after application confirmation)
- Have installation carried out
- Obtain the specialist contractor's certificate
- Submit evidence of use to BAFA
- Wait for payment
This article provides general information on funding and tax options. It does not replace individual advice from a tax adviser or energy adviser.
Why a certified energy adviser determines funding eligibility
Without a dena-approved energy efficiency expert (EEE), a BAFA window application will not be approved. This is a funding requirement rather than a recommendation. Skipping this step means losing up to 4,000 € in grants on a 20,000-€ project.
The iSFP (individual renovation roadmap) is more than a document for the funding application. It shows the economically sensible order of renovation measures and secures the 5-% BAFA funding bonus. EEE costs are typically 800–1,500 € for specialist planning and construction support on individual measures. These costs qualify for 50 % funding and are therefore not purely additional expenditure.
Cleverbauen24 supports owners with quote reviews for window replacement projects: the AI-assisted full review identifies missing Uw details, unlisted reveal work and quotes without RAL evidence. Through thevetted contractor network, specialist businesses are referred that understand the technical requirements for BAFA-eligible measures. Over 150 successfully supported projects and customer satisfaction of 4.8/5 demonstrate the service's reliability.
Professional tip: Before signing the contract, obtain written confirmation from the contractor that they will issue a specialist contractor's certificate using the official template once work is complete. Without this document, neither BAFA funding nor tax deductions under §35c are possible.
How much do new windows really save?
New windows noticeably reduce heat loss. For a detached house with 12 windows, window-related heat loss can fall from around 5,200 kWh to about 1,400 kWh annually. This translates into annual heating cost savings of 500–800 € from window replacement alone. Combined with other measures such as façade insulation, annual savings of 800–1,400 € are realistic.
| Scenario | Net investment after BAFA | Annual savings | Payback period |
|---|---|---|---|
| 10 uPVC windows, standard installation, 15 % BAFA | — | 500 € | 12 years or more |
| 10 timber windows, RAL installation, 20 % BAFA (iSFP) | approx. 15,760 € | 900 € | 17 years or more |
| 12 windows in a detached house, combined with façade, iSFP | approx. 18,000 € | 900–1.400 € | 13 years or more |
These payback periods assume constant energy prices. If gas prices rise, the period shortens accordingly. Installation quality also matters: a window with a thermal bridge at the reveal saves much less than calculated. RAL-compliant installation is therefore a question of actual savings as well as funding.
For an individual budget estimate, Cleverbauen24 offers a freeRenovation cost calculatorusing regional market data.
Step by step: from enquiry to funding payment
A realistic schedule for a ten-window project with BAFA funding:
- Obtain quotes (1–3 weeks):At least three quotes from specialist contractors, each with Uw details, installation method and separate lists of all items. Have quotes checked for completeness and plausibility.
- Energy advice and iSFP (2–6 weeks):Commission an EEE, arrange a site visit and have an iSFP prepared. Without an iSFP, the 5-% bonus is unavailable.
- Submit the BAFA application (before awarding the contract):Online through the BAFA portal. Processing time: 2–6 weeks. The contract may only be awarded after application confirmation is received.
- Award the contract and coordinate installation:Plan scaffolding and all trades (reveals, roller shutters, windowsills) together. Negotiate volume discounts with the manufacturer.
- Installation phase (1–4 weeks depending on scope):For 10 windows in a detached house, actual installation typically takes 3–7 working days.
- Obtain the specialist contractor's certificate:Immediately after completion, before submitting evidence of use.
- Submit evidence of use to BAFA:With invoices, certificate and proof of payment. Payment generally arrives within 4–8 weeks of submission.
Practical coordination tips:
- Combining scaffolding and installation of all windows saves 500–1,000 € compared with multiple separate visits
- Negotiate manufacturer volume discounts from 5 windows (typically 5–10 %)
- Check quotes for missing Uw details, unlisted reveal work and missing RAL evidence
- Forenergy refurbishment: if planning several measures, agree the sequence with the EEE to benefit from shared scaffolding and funding opportunities
Key findings
Window replacement in 2026 costs between 600 and 2,500 € per window, with BAFA funding through an iSFP reimbursing up to 20 % of eligible costs and a certified energy adviser being mandatory.
| Topic | Details |
|---|---|
| Cost per window 2026 | 600–2,500 € including installation, depending on material and method |
| BAFA funding | 15 % basic funding, 20 % with iSFP; limit 30,000 € or 60,000 € per residential unit |
| Technical minimum requirement | Uw ≤ 0.95 W/(m²K) for BAFA eligibility; triple glazing recommended |
| Hidden additional costs | Reveals, removal, scaffolding and windowsills can total 500–2,000 € per project |
| Cleverbauen24 | Quote review (free Quickcheck, full review from 79 €) and referrals to vetted specialist contractors |
Cleverbauen24 helps you avoid losing window replacement funding
Many owners lose funding because of incomplete quotes rather than missing applications: no Uw-value stated, reveal work priced as a lump sum, RAL installation unconfirmed. Cleverbauen24 uses AI to review your window quote for precisely these weaknesses before you sign.
The freeQuickcheckprovides an initial assessment within minutes. The paid full review from 79 € analyses your quote for completeness, funding eligibility and alignment with market prices. Through its vetted contractor network, Cleverbauen24 refers specialist contractors who issue BAFA-compliant certificates and document RAL installation. If you already have a specific quote, submit it directly on thequote review pageand receive transparent feedback before setting your budget.
Further official sources on window replacement
The following bodies are authoritative for funding applications, technical requirements and tax questions:
- BAFA: Federal Funding for Efficient Buildings (BEG EM):Applications, funding requirements, Uw requirements and evidence of use for individual measures
- KfW: replacing windows with government funding:Supplementary loan 358/359 and Efficiency House programme 261, terms and combination rules
- Federal Ministry of Finance: §35c EStG:Tax support for energy refurbishment, deductions and restrictions on combining support
- Consumer advice centre:Independent advice on quotes, contractor agreements and funding applications; guidance on typical pitfalls when awarding contracts
- dena: energy efficiency expert list:Search for approved EEEs for BAFA applications and iSFP preparation
- RAL-Gütegemeinschaft Fenster, Fassaden und Haustüren:Technical requirements for RAL warm installation and evidence of quality
FAQ
What does window replacement cost per window in Germany in 2026?
Replacing a window in 2026 costs between 600 and 2,500 € including installation, depending on material and installation method, based on a standard size of 150 × 120 cm. uPVC is at the lower end; timber-aluminium at the upper end.
What does installing 10 new windows cost in total?
For 10 windows in a detached house, costs of 6,000–25,000 € are possible, depending on material and specification. Typical project expenditure is 12,000–18,000 € before funding when RAL installation, reveal work and scaffolding are included.
How much government funding is available for window replacement?
Through BEG EM, BAFA provides basic funding of 15 % of eligible costs, rising to 20 % with an iSFP. The limit is 30,000 € without an iSFP and 60,000 € with an iSFP per residential unit. Requirements are a Uw-value ≤ 0.95 W/(m²K) and involvement of an approved energy efficiency expert.
Can I claim window replacement against tax?
Yes, under §35c EStG, 20 % of costs can be deducted from income tax over three years, up to 40,000 € per property. Alternatively, §35a EStG allows 20 % of labour costs up to 1,200 € annually. Combining this with BAFA funding for the same measure is excluded.
Do I have to commission an energy adviser?
BAFA funding requires involvement of a dena-approved energy efficiency expert (EEE). Without an EEE, the application is not approved. Tax deductions under §35c do not necessarily require an EEE, but do require a specialist contractor's certificate using the official template.
Recommended
- Façade insulation costs 2026: WDVS, prices and funding | cleverbauen24
- What does renovation cost in 2026? Cost overview by trade | cleverbauen24
- Bathroom refurbishment costs 2026: what does a new bathroom cost? | cleverbauen24
- Kitchen renovation costs 2026 – what owners should budget | cleverbauen24
This article was created with AI assistance and reviewed by the editorial team.
Comments
No comments yet — be the first to contribute.