BIM in construction contracts: Legal issues and need for regulation

Digital building models enable closer collaboration between project participants. Information is shared, planning statuses are reconciled, and errors are detected at an early stage. However, the more interlinked the processes become, the more important the question of responsibilities among the project participants becomes. This is because, although the BIM method changes the way work is carried out, it does not invalidate the applicable law. It is crucial to clearly regulate the scope of services, responsibilities and usage rights already in the contract.

What actually is BIM?

Building Information Modeling (BIM) can be translated into German as building information model or building information management. Its defining feature is the use of three-dimensional digital building models in the processes of planning, construction execution and operation of buildings. Instead of drawing, modelling is carried out on the computer using three-dimensional building components whose objects can be linked to additional data.

From the interim planning steps, BIM models are created that ultimately represent databases and can be imported and evaluated by other project participants using computer-based methods. A BIM model initially enables a three-dimensional representation of the planning status; based on the geometric information, collisions between different discipline-specific models can be automatically detected at an early stage. When linked with additional attributes relating to schedule, cost and quality, a so-called n-D model is created. For project-wide data exchange, the open industry standard IFC has become established, and for communication regarding coordination needs, the BIM Collaboration Format (BCF) is used.

In practice, this means an integrative planning approach: instead of working sequentially one after the other, a joint design by different disciplines – architectural design, technical building services, structural design – is created simultaneously on a uniform overall BIM model. So far, this way of working is mainly common in the planning service phases; in the construction phase, the use of BIM models remains more of a specialist field for design-and-build or general contractors, and their continuation into the operational phase is still hardly established. For this method to work in a project, clear contractual provisions are required specifying who delivers which models in which quality at what point in time and how collaboration is organized.

Scope of services and fees

To implement BIM contractually in a construction project, project participants are obliged to provide deliverables as BIM models and to participate in collaboration processes using these models. These specific individual services are referred to as BIM use cases; their number and level of detail largely determine the scope of BIM application in a project and the associated effort. In practice, these BIM use cases are typically defined in a contract annex, the so-called Employer’s Information Requirements (EIR). How the project participants implement these specifications technically is regularly defined by the project participants during the planning process in the BIM Execution Plan (BEP) .

EIR and BEP are the legal pivot of every BIM project. It is not sufficient to merely stipulate the use of BIM in abstract terms. In that case, the content and scope of the BIM use cases and their implementation would remain completely unclear. The intention of the contracting parties would then have to be determined based on the general principles of contract interpretation in accordance with sections 133 and 157 of the German Civil Code (BGB), which would pose a considerable risk for both sides.

In addition, perhaps the most practically important legal question for designers and clients is how BIM services can be classified in terms of fee law. After the binding price character of the HOAI has been removed, the HOAI fee calculation remains a non-binding reference point for fee negotiations. The question of whether a BIM service is to be classified as a basic service or as a special service within the meaning of section 3 (2) HOAI therefore remains relevant. According to the prevailing view, it is not decisive for this distinction whether BIM models are created or edited. The service profiles of the HOAI are fundamentally designed to be method-neutral. The application of BIM is merely a technical tool for solving a planning task. What is decisive, therefore, is whether the planning task as such constitutes a basic or a special service: if a basic service is performed in terms of content using BIM, it remains a basic service – it does not become a special service merely because the method is used.

From this, some basic principles can be derived for practice. Planning with BIM models instead of classic two-dimensional floor plans, sections and elevations is merely a different form of representation of the same intellectual planning service and is therefore a basic service. BIM coordination – the merging and reconciliation of the discipline-specific models, including automated clash detection – also only replaces conventional coordination processes and is therefore, as part of the coordination services owed anyway under the respective service profiles, generally itself a basic service.

The aforementioned services are the minimum required in order to implement planning with BIM. On the basis of the coordinated discipline-specific models, further BIM use cases can be implemented which generally constitute special services. Such BIM use cases that are to be classified as special services include the preparation and updating of the BEP, model-based scheduling, higher-level BIM management services, etc.

BIM can also have an impact on the timing of planning effort. A characteristic of working with BIM is that detailed information must already be available in an early project phase in order for automated data exchange processes to function, which shifts planning effort into earlier HOAI service phases (e.g. bringing forward detailed design or more in-depth cost determination during preliminary design).

The contracting parties should therefore, in order to avoid later disputes, create clarity and define the scope of services and the fees owed for them clearly at the time the contract is concluded. In addition to agreeing BIM use cases in the EIR, the service profiles to be commissioned must be modified for this purpose. Specifically, the basic and special services in relation to the BIM method must be clearly identified and assigned to the respective service phases. Standard service profiles for the use of BIM have been published, for example, by the Federal Chamber of Architects (BIM for Architects, 2017), by the Committee of Associations and Chambers of Engineers and Architects for the Fee Structure e.V. (AHO Booklet No. 11, 2019) or by the Federal Institute for Research on Building, Urban Affairs and Spatial Development (BBSR) at the Federal Office for Building and Regional Planning (BBR) (Final report on the evaluation of the planning areas of the HOAI, 2024).

What else should be regulated in the BIM contract

In addition to defining the scope of services and the remuneration owed for them, it is advisable to include supplementary provisions in the contract for the application of BIM. In practice, this is sometimes done using Special Contract Conditions for the Use of BIM (BIM-BVB) attached to the contract as an annex. By using BIM-SCC, it can be ensured that all project participants, beyond the specific contractual relationship, can and must work together on the basis of a generally valid regulatory structure. Typical regulatory content in BIM-SCC includes, for example, derivations of conventional drawings from BIM models, provisions on updating the BEP, technical coordination processes, data exchange and data security, etc. A complete sample set of BIM-SCC has been published by the Federal Ministry of Transport and Digital Infrastructure (BIM4INFRA2020, Sample Special Contract Conditions BIM, 2019).

Impacts of BIM on liability, acceptance, and insurance

In conventional contract models, in which several project participants do not conclude a joint contract, the general civil-law principles of liability apply. Each planning participant is liable in the respective contractual relationship only for their own planning errors. Liability for the planning errors of others may arise in the event of a breach of the duty to warn of concerns. As with conventional planning, joint and several liability of several planning participants may also exist. However, collaborative work in a BIM model does not lead to an expansion of liability for defective services provided by other planning participants. The enforcement or defense of claims may, however, be made more difficult when using the BIM method if the project participant bearing the burden of pleading and proof can no longer specifically attribute defective performance contributions.

Planning services must, after proper contractual performance, in principle be accepted and in this respect do not differ from construction services. BIM models can also be the subject of acceptance. In construction practice, however, planning services are only rarely expressly accepted, due to the lack of their embodiment in the structure.

According to the case law of the Federal Court of Justice (BGH), where planning or supervisory errors have been realized in the structure, there is a claim for damages in addition to performance, aimed at compensation or an advance for the costs required to remedy the defect in the structure. If a BIM model is also intended to serve the later operation of the building, subsequent performance, i.e. correction of the defective planning in the BIM model, is also likely to be considered.

If the scope of services is limited to the use of the BIM method to provide planning and supervisory services, there are likely to be no special features with regard to the planner’s professional liability insurance, since liability insurance policies generally cover all liability risks arising from services belonging to the professional profile.

Copyright: Who owns the digital building model?

The use of the BIM method does not change the principles of copyright law. Planning services may be protected within the meaning of Section 2 of the German Copyright Act (UrhG) if they are works of individual intellectual creation. The decisive factor is the aesthetic impression that the work conveys according to the average judgment of a person receptive to "questions of art." If the planner creates something new, the work is, in case of doubt, protected by copyright. If they merely combine known planning elements, the work will generally not be protected by copyright.

It is therefore advisable – not only when applying the BIM method – to regulate contractually how and to what extent planning results protected by copyright may be used or exploited, modified, and passed on.

Conclusion: Legal certainty begins before the first model

BIM creates new opportunities for collaboration. Anyone wishing to use the BIM method successfully should also place importance on clear contract design. This includes, in particular, defining which BIM-specific services are owed and  how they are to be remunerated. Depending on the project and the scope of use of the BIM method, further provisions may be advisable. Clarifying BIM-specific issues before the start of the project reduces the risk of later disputes.

Literature reference: The principles set out here are essentially based on the commentaries by Eschenbruch/Elixmann in Beck’s HOAI and Architects’ Law Commentary, Fuchs/Berger/Seifert, 3rd edition 2022, before Sections 650p et seq., marginal nos. 1034 et seq., and Bodden in Lederer, Contract and Fee Structuring for Architectural and Engineering Services, 4th edition 2025, Chapter 2, Section 1.10.