Building Modernization Germany 2026: GModG, GEG and Funding
Building modernization in Germany is being re-shuffled right now. The current Building Energy Act (GEG) still applies, but on 13 May 2026 the Federal Cabinet adopted the draft Building Modernization Act (GModG), which would scrap the rigid 65% renewable rule and replace it with a graduated bio-fuel admixture from 2029. Until parliament passes GModG, the existing GEG remains binding. The KfW 458 grant still gives you up to 70% (capped at €21,000) on a heat pump.
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Key Takeaways
- Cabinet decision 13 May 2026: Germany plans to roll back the GEG 65% renewables rule and switch to a bio-fuel ramp from 2029. Not law yet.
- §71 GEG 65% rule still applies to cities above 100,000 residents until 30 June 2026, to smaller municipalities until 30 June 2028.
- KfW 458 heat-pump grant stacks: 30% base + 20% heat-replacement bonus + 30% income bonus (household income ≤ €40,000). Max €21,000 on €30,000 eligible cost.
- BAFA energy advice (EBW): 50% subsidy, capped at €650 (1-2 family) or €850 (multi-family). The 80% figure from older articles ended in 2024.
up to €21,000
KfW 458 heat-pump grant
65%
Renewables from 30.06.2026 (large cities)
2045
Climate-neutral target (unchanged)
What the Cabinet decided on 13 May 2026
The Federal Cabinet signed off on the draft Building Modernization Act (GModG). The draft now goes to the Bundestag. Until it passes both chambers, the Building Energy Act (GEG) in its current 2024 version remains the law you renovate under.
What the draft proposes:
- The hard 65% renewables rule in §71 GEG goes away.
- A bio-fuel staircase replaces it. From 2029, liquid and gaseous fuels must contain a growing share of bio or synthetic components.
- The 2045 climate-neutral target for buildings stays. The route there becomes more flexible.
Source: BMWE press release, 13.05.2026.
What the GEG actually obliges you to do in 2026
§71 GEG: the 65% renewables rule
If your home is in a municipality with over 100,000 residents (measured 01.01.2024), the deadline is hard: until 30 June 2026 you may still install a new heating system that does not use 65% renewable energy, but only under transition conditions. For smaller municipalities the deadline shifts to 30 June 2028.
Source: §71 GEG, gesetze-im-internet.de.
§72 GEG: 30-year boiler limit
Constant-temperature boilers (Konstanttemperaturkessel) burning oil or gas may not run beyond 30 years. The exemptions matter:
- Condensing and low-temperature boilers (Brennwert / Niedertemperatur) are exempt. Most boilers built after 1996 fall here.
- Output below 4 kW or above 400 kW is exempt.
- Owner-occupiers of a one- or two-family house who have lived there since 1 February 2002 are exempt.
- Heat pumps, pellet, biomass are not boilers in this sense, so §72 does not apply.
- After purchase, gift or inheritance, you get two years to replace a non-compliant boiler.
Source: §72 GEG, gesetze-im-internet.de.
BEG Funding 2026: what KfW 458 actually pays
The heating replacement grant runs through KfW programme 458. As of May 2026 the grant stacks like this. Maximum cash grant: €21,000.
| Measure | Base | Bonus | Max | Cap |
|---|---|---|---|---|
| Heat pump (air-to-water) | 30% | +20% heat-swap / +30% income | up to 70% | €30,000 |
| Pellet / biomass heating | 30% | +20% / +30% | up to 70% | €30,000 |
| Solar thermal (hybrid) | 30% | +20% / +30% | up to 70% | €30,000 |
| Roof and basement insulation | 15% | +5% with iSFP | up to 20% | €30,000 |
| Windows and façade | 15% | +5% with iSFP | up to 20% | €30,000 |
Source: KfW programme 458.
Apply BEFORE you award the contract
You must file the KfW application before you sign the contract with your installer. Sign first, apply later, and you lose the entire grant. Current processing time is 4-8 weeks. Build that delay into your timeline.
Energy consulting: 50%, not 80%
The single most-misquoted number on German renovation pages. The BAFA Energy Consulting for Residential Buildings programme (EBW) used to fund 80% before 2024 and was reduced to 50% in the federal budget consolidation. As of May 2026:
| Building type | Subsidy | Cap |
|---|---|---|
| 1-2 family house | 50% | €650 |
| 3+ units residential | 50% | €850 |
A full on-site energy audit costs €1,300-1,800 in 2026. After the 50% subsidy, you pay €650-1,150 out of pocket. The resulting renovation roadmap (iSFP) unlocks an extra 5% on every later BEG grant.
Source: BAFA Energieberatung Wohngebäude.
Financing the gap: which loan fits
Even with a 70% grant, most owners face €8,000-20,000 of uncovered cost on a heat-pump swap and far more on insulation and windows. Three sensible paths.
Modernisierungskredit (no land register)
A consumer loan dedicated to renovation; no Grundschuld notary, fast payout, terms 12-120 months. Cheapest option when you do not want a notary appointment.
Compare offersSanierungskredit (Denkmalschutz)
Purpose-bound loan for listed buildings or deep renovation. Typically carries better terms and combines with regional Denkmalschutz funding.
Check SanierungskreditBaufinanzierung (from €50,000)
For full renovations above €50,000, a mortgage works better. KfW programmes 358/359 add an interest-subsidised supplementary loan.
Baufinanzierung 2026For heat-pump-specific bridge financing, see our Kredit für Wärmepumpe-Förderung 2026 guide covering the grant pre-financing case. To see the broader picture, browse our loan comparison hub.
Renovation order: insulation before heating
The most expensive mistake expats make: swap the heater first, insulate later. A heat pump in an un-insulated house is over-sized, runs inefficiently, and costs more for decades. Recommended order:
Energy consulting with iSFP
€1,300-1,800, 50% BAFA subsidy. The roadmap raises every later BEG grant by 5%.
Roof and basement insulation
Biggest leverage per euro. 15% BEG funding, +5% with iSFP.
Windows and façade insulation
Bundled when scaffolding is already up.
Heating swap
Correctly sized now because the building envelope demands less.
Heating systems 2026 compared
| Type | Cost (single-family) | Funding | Older-home fit |
|---|---|---|---|
| Air-to-water heat pump | €25,000-35,000 | up to 70% | good for insulated stock |
| Ground-source heat pump | €35,000-50,000 | up to 70% | very good, high SCOP |
| Pellet heating | €25,000-32,000 | up to 70% | good for older homes with storage |
| Solar thermal (add-on) | €8,000-12,000 | up to 70% | sensible as hybrid |
| Hybrid gas + solar | €18,000-25,000 | only solar share | limited GEG compliance |
The detailed 20-year cost curve is in our Heat pump vs. gas heating 2026 guide.
Municipal heat planning: ask before you invest
By 30 June 2026, cities above 100,000 residents must publish their municipal heat plan (kommunale Wärmeplanung). Smaller municipalities have until 30 June 2028. The plan tells you whether your address falls into a future district-heating zone, a hydrogen expectation zone, or stays on individual supply.
Installing a heat pump in a planned district-heating area means paying for two heating systems. Ask your Stadtwerk or municipal climate office before you invest.
The Verbraucherzentrale keeps a list of cities that have already published plans.
This week, do three things
- Check your boiler age. Type plate or maintenance log. Installed before 1996 and not a condensing model, then §72 GEG is in play.
- Ask the city about heat planning. Stadtwerk, climate-protection officer, or Bauamt. A five-minute call.
- Estimate your funding gap. Use the table above for a rough number and compare a matching Modernisierungskredit in two minutes, free.
Building Modernization Germany 2026: FAQ
What does the new Building Modernization Act (GModG) change?
The Cabinet draft of 13.05.2026 would scrap the rigid 65% renewable rule in §71 GEG and replace it with a bio-fuel ramp from 2029. The 2045 climate-neutral target stays. Until both chambers pass GModG, the current GEG remains binding.
Do I have to replace my heating in Germany in 2026?
Not necessarily. §72 GEG only forces a swap on constant-temperature oil or gas boilers older than 30 years. Condensing boilers, units below 4 kW or above 400 kW, heat pumps, biomass, and owner-occupiers of a 1-2 family house since 2002 are exempt.
How big is the heat-pump grant in Germany 2026?
Up to 70% via KfW 458: 30% base + 20% heat-replacement bonus + 30% income bonus (household income ≤ €40,000). Maximum cash grant €21,000 on €30,000 eligible cost.
How much does BAFA pay for energy consulting now?
50% of eligible costs, capped at €650 for 1-2 family houses and €850 for larger residential buildings. The 80% rate cited in older guides ended in 2024.
What is kommunale Wärmeplanung and why does it matter?
It is the municipal heat plan. Cities above 100,000 residents must publish theirs by 30 June 2026, smaller municipalities by 30 June 2028. The plan determines whether your address connects to district heating, a hydrogen-ready grid, or stays on individual supply. Check before investing in a new heater.
Which renovation loan suits me?
For amounts up to €50,000 without a notary, a Modernisierungskredit (consumer loan) is fastest. Above €50,000, a Baufinanzierung mortgage works better. If you need to bridge the BEG grant, a purpose-bound Sanierungskredit or KfW supplementary 358/359 fits.
When does GModG actually take effect?
The draft is now in parliament. A realistic timeline is second half of 2026 for adoption, with entry into force following the legislative process. Until then, GEG 2024 remains in force.