Funding & Bureaucracy · Chapter 28
The funding-traps checklist
The sequence trap, the 60% cap, Widerruf timing, market register and prepayment — compact and checkable.
As of 2026 — rules change; verify with the funding body if in doubt.
Funding is valuable, but it's full of sequence and timing traps. This list gathers the most important ones to tick off.
Before ordering
- Apply before ordering. Never sign the binding contract before the funding application — or have the conditional clause (funding-approval proviso) put into the order confirmation. The actual "start of works" is delivery/installation, not the conditional signature.
- Sort the BzA. Make sure the specialist firm issues the BzA and you know what details it needs from you.
- Second residential unit / old oil boiler — report early; can affect the subsidy amount.
When stacking multiple grants
- Mind the 60% total cap: KfW + municipality together often may only use up to 60% of eligible costs. With high KfW funding, the municipal grant can shrink.
- Order: the municipal application usually comes after the KfW approval (the KfW notice is required) but before construction starts.
At contract and signatures
- Widerruf timing: don't prematurely waive your 14-day cancellation right before scope-critical points (price, scope, "up to X kWp" clauses) are confirmed in writing.
- Prepayment structure: payment plans are often front-loaded (e.g. 60% after delivery, 40% before commissioning) — you pay before everything runs. Combined with retention of title, the firm owns the system until full payment. Insure the system meanwhile.
After installation
- Get the BnD from the firm (after your payment) — with it you draw the grant.
- Marktstammdatenregister: mandatory, within ~1 month of commissioning, by you, free, online.
- Municipal final documents submitted on time (often the KfW payout notice + invoices, within a few months).
In short, to tick off: (1) apply/condition before ordering, (2) secure the BzA, (3) check the 60% cap, (4) waive Widerruf only after scope confirmation, (5) consider prepayment + retention of title, (6) get the BnD, (7) register the market data yourself.
To close this stage: from a signed offer to a running system.
In this section
KfW heating subsidy: the process
The strict sequence from BzA through application and approval to payout — and the one trap many miss.
KfW loan 358/359 via your bank
Who gets the low-interest supplementary loan, how it fits the sequence, and what the bank checks.
Stacking municipal grants
Municipalities often fund on top — how it interacts with KfW, the 60% cap, and a cautionary tale.
From signed offer to running system
The steps after signing — engineering, sign-off, grid registration, installation, meter swap, commissioning.