
You have the choice
Contract models in building construction
With Implenia, you have the choice and can choose between all standard and new contract models for the planning and execution of your projects.
Total contractor (TU)
Transfer of overall responsibility for all phases of the project
With the total contractor model, the construction company assumes overall responsibility for all phases of the project - from planning and coordination through to turnkey implementation. This means that the client has a single point of contact throughout all phases, as well as quality and cost certainty. A contract for work and services is concluded between the client and the total contractor. This essentially stipulates the planning and execution services, the remuneration and the deadlines. There are classic forms such as
- Lump-sum contract: The general contractor guarantees to carry out the project within the agreed lump-sum remuneration (including inflation).
- Global contract: Fixed remuneration with subsequent billing of inflation in accordance with standard industry billing procedures.
- Contract with cost ceiling: Agreed and guaranteed upper work price limit with transparent billing of the actual net construction costs. If the costs fall below the cost ceiling, the difference is split according to the agreed arrangement. The general contractor is always liable for any overrun of the upper price limit.
- Contract with open invoicing: The general contractor is paid the stated net construction costs plus the project management fee (general contractor fee). The cost and schedule risks are borne by the general contractor within the framework of the contractual agreements.
The client concentrates exclusively on strategic decisions and its own core competencies. Involving the general contractor in the planning process at an early stage is important so that the general contractor can make the best possible use of its experience and expertise to ensure that the construction project is completed on time, on budget and to the highest quality. If the total contractor does not provide the services itself, it concludes separate contracts with planners, specialists, contractors and suppliers in its own name and for its own account.
Advantages of the total contractor (TU)
- Cost, quality and deadline certainty
- Only one contact person and therefore fewer interfaces and coordination effort for the client
- Turnkey implementation and planning responsibility lie with the total contractor - planning and implementation expertise from a single source
- Clear assignment of responsibilities in warranty cases
General contractor (GU)
Construction of a turnkey building
The general contractor is an experienced service provider who constructs turnkey buildings tailored to user requirements. The general contractor is responsible for ensuring quality, deadlines and cost certainty during execution.
With this model, the client has a single point of contact for planning with the planning team and for execution with the general contractor. In addition to monitoring activities, the client also coordinates between planning and execution. The contractual relationship with the general contractor is a contract for work and services (see Total contractor section).
Advantages of the general contractor (GU)
- Cost, quality and deadline certainty
- Execution competencies from a single source
- Simpler allocation of responsibilities in warranty cases
General planner (GP)
Coordination of all planning services
With the general planner, the client has a single point of contact for the planning of the construction project. The general planner is responsible for coordinating all planning services (and in some cases also execution services).
In contrast to awarding planning services to individual contractors, the responsibility for preparing the necessary project planning documents can be transferred to a general planner. This means that the client has only one contact and contractual partner during the planning process. The general planner is responsible for coordinating all planning services. The general planner can also coordinate the planners during execution.
Advantages of a general planner (GP)
- Cost, quality and deadline certainty
- Greater flexibility and design freedom
- Independently regulated contractual relationships in planning and execution
- Faster and more economical execution of planning
- Flexibility in the execution model due to possible switch to GC or TU
Integrated Project Delivery (IPD) and project alliances
Integrated Project Delivery, IPD means "integrated project delivery".
This approach creates an environment in project work that promotes collaboration, innovation and value creation. It also incorporates approaches from the lean management philosophy.
Goal: Increase efficiency in real estate projects and improve results
Cost overruns, delays, loss of quality, inefficient planning and execution, dissatisfied investors, buyers and users - the list of challenges in the real estate industry is long. Implenia wants to promote transparent, goal-oriented and partnership-based collaboration and is launching pilot projects based on the Integrated Project Delivery (IPD) approach.
Five equally important core elements of IPD
- Early involvement of stakeholders: Continuous collaboration between clients, planners and contractors from project inception to completion
- Joint opportunity and profit strategy: performance-based and transparent remuneration for all project participants according to the motto "all win or all lose"
- Joint project management: All project team members work in an integrated manner, even across company boundaries, on an equal footing and bear joint responsibility for the success of the project.
- Multi-party contract between clients, planners and contractors: The objectives are jointly defined between all parties involved and cooperation is regulated in terms of culture, organization, methods and processes, and the remuneration system is agreed.
- Liability and project insurance: Mutual exclusions of liability promote a common alignment of interests and enable trust-based working.
Project alliances in accordance with SIA 2065 Planning and building in project alliances
Ideally, the client and construction company should work together on a construction project - at least that's the theory. The reality, however, is characterized by legal requirements and practical challenges that can lead to unforeseen events despite the best planning of the project. In such cases, conventional construction contracts clearly place the risk on one party - the construction company or the client. As a result, all parties involved prioritize their own interests first and foremost.
Implenia takes a firm stance against this dynamic and has always focused on the construction project and the best possible implementation of the client's requirements. The project managers prefer to work in partnership with their customers as equals. Implenia is convinced that this is the only way to achieve a win-win situation. Jens Vollmar, Head Division Buildings and from 1.4.2025 CEO at Implenia as well as Vice President Development Switzerland and member of the Board Building Switzerland:
"Large, complex projects cannot be successfully planned and realized without efficient collaboration based on partnership and trust. At a time when conventional processes and contract models are no longer effective, I firmly believe that we need to gear our organization, our processes and the way we manage projects towards partnership-based collaboration."
Implenia therefore welcomes the Swiss Society of Engineers and Architects' (SIA) draft of the SIA 2065 Code of Practice on Planning and Building in Project Alliances: In it, the association presents the work contract-like alliance contract - an approach to cooperative project management that we believe can become a valuable tool for the construction industry.
The project alliances introduced by SIA are based on principles that promote cooperation in a spirit of partnership and focus on the joint success of the project. The alliance partners agree on
- cooperative collaboration,
- a trusting and respectful relationship,
- refraining from apportioning blame and instead using conflict resolution mechanisms.
- a commitment to common project goals,
- and transparent communication.
The alliance agreement is the legal basis for a cooperative partnership. This is accompanied by the implementation of an incentive system to promote the interests of both parties and an exclusion of liability for intent and gross negligence. The parties jointly assume risk management, which puts conflicts in the background and constructive solutions in the foreground.
Unfortunately, unlike contracts for work and services, there is currently no legal basis for project alliances and model contracts have yet to be drawn up. The details are therefore currently in the hands of the parties involved. A corresponding standardization would give the alliance partners legal certainty and add a valuable form of cooperation to the law. Implenia is therefore advocating a corresponding legal basis and hopes that this will contribute to a fair, trusting and cooperative Swiss construction industry.