General Terms and Conditions

§ 1 Scope, Order of Precedence and Interpretation

1.1 Contractual basis. Binding first is the offer or fee agreement signed by the client, including all annexes (the individual principal document). Subordinate to this are these GTC, then the Fee Schedule for Architects and Engineers (HOAI 2023), and finally the German Civil Code (BGB) in its respective applicable version.

1.2 Rejection of conflicting terms. Conflicting or supplementary terms and conditions of the client become part of the contract — even where known — only if Keystone expressly confirms this in writing. In the event of conflict, the provisions under 1.1 take precedence over third-party GTC.

1.3 Severability-based interpretation. In cases of doubt as to interpretation, a sustainable, mutually economically sensible and lawfully balanced solution shall be taken as the basis.

§ 2 Conclusion of Contract and Scope of Services

2.1 Validity period of the offer. Written offers remain binding for 30 calendar days from the date, unless otherwise noted. Keystone accepts qualified electronic signatures (§ 126a BGB) as a fully valid conclusion of contract.

2.2 Scope of services. The scope of services is determined primarily by the basic services of the respective service phases as defined in the HOAI. Services outside the basic services (“special services”) must be commissioned and remunerated separately; for these, Keystone prepares a supplementary offer.

2.3 Service Phase 4 (approval planning). Service Phase 4 is provided in cooperation with a partner architect entered on the list of architects of the Chamber of Architects of North Rhine-Westphalia. The remaining service phases LP 1–3 as well as LP 5–9 are performed by Keystone directly.

2.4 Change management. The client’s change requests must be submitted in writing; Keystone examines the technical, scheduling and financial implications and submits a written supplementary offer.

§ 3 Client’s Duties to Cooperate and to Provide

3.1 Provision of documents. The client guarantees the completeness, accuracy and lawfulness of all information provided. Digital data must be provided in customary, open-source-compatible formats (IFC, DWG, PDF, XLSX).

3.2 Decision deadlines. Approvals must be granted in writing within the deadlines stated in the offer. If approvals are not granted, performance deadlines are extended accordingly; additional costs are borne by the client.

3.3 Sustainability data. To fulfil ESG reporting obligations, the client provides the necessary building-material and energy data in verified form.

§ 4 Remuneration, Payment Terms, Default

4.1 Basis of remuneration. Remuneration is based on the chargeable costs and fee zones pursuant to HOAI 2023. For project terms exceeding 12 months, fee rates are updated annually pro rata temporis on the basis of the official construction price index of the German Federal Statistical Office.

4.2 Instalment and final invoices. For order values below €3,000.00 net the following applies by way of derogation: 50% down payment on commissioning, 50% on completion/delivery. Otherwise, instalments fall due monthly according to the progress of services. The client must check invoices for formal defects within 7 days; thereafter the invoice is deemed accepted.

4.3 Payment term and discount. Unless otherwise agreed in writing, invoices are payable without deduction within 10 calendar days of receipt. For payments received in full within 5 calendar days of receipt of the invoice, we grant a 1.5% discount (Skonto) on the net amount; the discount is excluded for third-party/pass-through costs and for rebates already granted. The receipt of payment in our account is decisive. Electronic invoices are deemed received on the day of dispatch.

4.4 Default. If the payment term is exceeded, the client falls into default from the following day (day 11) without further reminder (§ 286 (2) No. 1 BGB). Default interest amounts to 5 percentage points above the base rate for consumers and 9 percentage points above the base rate for entrepreneurs (§ 288 BGB); any further damage may still be claimed. For non-consumers, a flat fee of €40.00 (§ 288 (5) BGB) is charged. A fee of €7.50 applies for each reminder; all further appropriate costs of legal pursuit (collection, court, lawyer) are borne by the defaulting debtor.

4.5 Right to refuse performance and right of retention. In the event of default exceeding 30 days, Keystone may suspend work until payment is made in full and may retain plans, models and digital data until all due claims are settled.

§ 5 Deadlines, Delivery Periods, Force Majeure

5.1 Binding nature of deadlines. Only fixed deadlines agreed in writing are deemed contractually binding. For deviations of less than 5 working days, no delivery delay exists.

5.2 Force majeure. In the event of natural events, pandemics, official orders or cyberattacks, the performance obligations are suspended for the duration of the impediment plus a start-up period; deadlines shift accordingly.

5.3 Sustainable resilience. Keystone operates an ISO-27001-compliant emergency and crisis management to safeguard digital building models.

§ 6 Liability

6.1 Extent of liability. Keystone is liable without limitation for intent and gross negligence. In the case of ordinary negligence, liability is limited to the coverage amounts of the professional and business liability insurance (€5 million for personal injury / property damage, €1 million for financial losses).

6.2 Exclusions of liability. Liability for lost profit or loss of production is excluded, unless there is intent or gross negligence. Liability for data loss is limited to the typical cost of restoration.

6.3 Mitigation of damage. The client must report recognisable risks to us in writing without delay.

§ 7 Claims for Defects

7.1 Duty to give notice of defects. Obvious defects must be notified in writing within 14 days of acceptance of the service, hidden defects within 14 days of discovery.

7.2 Subsequent performance. Keystone decides at its reasonable discretion between rectification or substitute performance; the client must grant a reasonable period for subsequent performance.

7.3 Warranty period. The period is five years from acceptance (§ 634a (1) No. 2 BGB).

§ 8 Copyright and Rights of Use

8.1 Content of rights. Upon payment in full, the client receives a simple, non-transferable right of use for the specific project. Any use beyond § 31 (5) UrhG (German Copyright Act) requires a written licence.

8.2 Reservation of rights. Keystone reserves a non-exclusive right to use the project results for its own promotion, provided no confidentiality interests conflict with this. In the event of default exceeding 60 days, Keystone may revoke rights of use granted.

§ 9 Termination

9.1 Ordinary termination by the client (§ 648 BGB). The client may terminate at any time; Keystone retains its claim to the agreed remuneration less saved expenses. Saved expenses are set at a flat rate of 5% of the remaining remuneration, unless the client proves a lower loss.

9.2 Extraordinary termination by Keystone. Keystone may terminate without notice in the event of default exceeding 30 days as well as in the event of serious failures to cooperate or breaches of sustainability-relevant compliance requirements.

§ 10 Confidentiality and Data Protection

10.1 Secrecy. All non-publicly known information, business and trade secrets are treated confidentially. The duty of secrecy applies for five years from the end of the contract, and indefinitely for personal data pursuant to the GDPR.

10.2 Data processing. Personal data is used exclusively for the performance of the contract and project communication. The engagement of sub-processors requires a data protection agreement (Art. 28 GDPR); we provide a current list on request. Details on the processing via this website are set out in our privacy policy.

10.3 Protective measures. Keystone operates information security in accordance with ISO 27001.

§ 11 Sustainability, ESG & Integrity

11.1 Environmental and climate protection. Keystone consistently strives for the reduction of CO₂ emissions, the conservation of resources and a circular economy within the meaning of the EU Taxonomy. The client provides EPD data (Environmental Product Declarations).

11.2 Social responsibility. All companies involved respect the ILO core labour standards. Planning takes into account DIN 18040 et seq. on barrier-free design.

11.3 Good governance. Gifts exceeding €50 are declined and documented. Keystone maintains an anonymous whistleblower platform pursuant to the HinSchG (German Whistleblower Protection Act).

§ 12 Dispute Resolution

12.1 Arbitration board. General Consumer Arbitration Board (Allgemeine Verbraucherschlichtungsstelle), Straßburger Str. 8, 77694 Kehl (verbraucher-schlichter.de). Keystone declares itself willing to participate in a dispute resolution procedure.

12.2 Online dispute resolution. Platform of the EU Commission: ec.europa.eu/consumers/odr.

§ 13 Place of Jurisdiction and Applicable Law

For merchants, Bonn is the exclusive place of jurisdiction; Keystone remains entitled to sue the client at the client’s general place of jurisdiction. German law applies exclusively, to the exclusion of the UN Convention on Contracts for the International Sale of Goods.

§ 14 Final Provisions

Amendments and supplements to these GTC require the written form. Invalid provisions are replaced by valid ones that most closely approximate the economic purpose; the invalidity of individual clauses does not affect the validity of the contract in other respects.

§ 15 Right of Withdrawal for Consumers

For distance contracts as well as for contracts concluded away from business premises, consumers have a right of withdrawal pursuant to §§ 312g, 355 BGB. Details — including a model withdrawal form — are set out in the separate right of withdrawal notice.