Describe the work rather than just the room
Prepare an existing/proposed plan and a short list of elements affected: walls, floor buildup, shared risers, ducts, windows, façade, heating and access routes. Include heavy finishes, new openings and altered service connections. “My kitchen” does not explain whether the proposal touches structural safety, common equipment or another owner’s rights.
Under WEG section 5, structural/safety elements and installations serving common use cannot become private property merely because they lie within the apartment. Check the declaration of division, community rules, plans and relevant resolutions. Ask for qualified interpretation where the classification is disputed; do not infer ownership solely from who paid for the previous repair.
Identify the right decision and its scope
WEG section 20 addresses structural alterations beyond proper maintenance of common property. Have the proposed work classified before choosing a procedure. It is too broad to say every internal refurbishment needs unanimous consent, or that work within the unit never needs a community decision.
Ask the administrator what technical documents and resolution wording are required, how the proposal can reach the owners and when a decision can be made. An informal statement that the administrator has “no objection” should not be treated as the required owners’ resolution without checking authority. Even an entitlement to a suitable alteration does not mean you can simply select any execution and begin.
Make the decision practical for the actual works
| Question | Evidence to keep |
|---|---|
| What is permitted? | Dated scope, drawings, conditions and relevant decision |
| Who plans and checks the intervention? | Named competent specialists and agreed services |
| Who pays and maintains the result? | Allocation, reinstatement and future obligations |
| How are neighbours/common parts protected? | Noise, hours, access, protection and shutdown arrangements |
| What public procedure applies? | Applicable approval or documented check for this intervention |
| What counts as a change? | Route for revised drawings, price, permissions and programme |
In Berlin, project-specific public queries go to the district building authority. Community agreement does not replace public law, heritage requirements or technical design. Conversely, a public permission is not a substitute for the necessary WEG decision. Give the contractor the approved revision and conditions, not just a verbal summary.
Clarify costs without assuming the neighbours pay
WEG section 21 has different rules for costs and use of structural alterations. A privately requested intervention is not automatically shared by all owners. Have the resolution and facts assessed and identify who contracts with the builder. Keep a private renovation order separate from a community contract or a special levy.
If a cost already sits in the community contract, your documented contribution is the relevant household cash item; do not add both the full community contract and your share. Distinguish the community’s maintenance funds from your private contingency. Money in a communal account is not automatically available to finance your own apartment finishes.
Allow for preparation and temporary cash
| Item | Amount |
|---|---|
| Initial professional assessment | 1 190 |
| Structural design allowance for defined services | 1 785 |
| Drawings and coordination | 1 428 |
| Common-route protection | 714 |
| Agreed service shutdown and reinstatement | 357 |
| Specified technical checks | 952 |
| Preparation and checks subtotal | 6 426 |
| Defined execution package | 14 280 |
| Chosen execution reserve | 1 428 |
| Project funding excluding refundable security | 22 134 |
| Refundable security paid separately | 1 000 |
| Initial cash availability | 23 134 |
If EUR 250 of the security is legitimately used for a separately evidenced cost outside the package, EUR 750 returns. Final project cost becomes EUR 22,384, rather than EUR 23,134. Record the deposit, refund and actual charge distinctly. If the charge was already in the work package, reconcile it there instead of adding it again.
Start only from an understood version
- Clarify the property classification and procedure.
- Obtain specialist design and applicable community decision.
- Check public permissions independently.
- Agree cost responsibility, access and protection.
- Issue the approved revision to the trades.
- Retain checks, reinstatement evidence and payment records.
Use Reno Pro to separate private works, contributions, deposits and payments. Keep resolutions and technical documents with the budget. The useful outcome is an authorised, defined intervention with understood costs, not merely a folder containing a document with the word approval.
Sources, date and scope
- Bundesministerium der Justiz / Bundesamt für Justiz — WEG § 5 — Sondereigentum
- Bundesministerium der Justiz / Bundesamt für Justiz — WEG § 20 — Bauliche Veränderungen
- Bundesministerium der Justiz / Bundesamt für Justiz — WEG § 21 — Kosten baulicher Veränderungen
- Land Berlin — Senatsverwaltung — Informationsportal der Obersten Bauaufsicht
Checked on 19 October 2026. Local examples concern Berlin unless stated otherwise. Check state law, heritage protection, community rules and actual work for the specific project. Teaching figures are invented euro amounts, not market prices or offers. The article projects are independent. Tax and funding calculations apply only under the stated assumptions; competent professionals resolve project-specific technical and legal questions.