Project phases according to the SIA standards
In Switzerland, architecture firms structure their services according to the standards issuedby the Swiss Society of Engineers and Architects (SIA).
These standards define the project phases, the standard architectural services, and the waya construction project is developed, authorised, and executed.
This framework provides a clear structure to ensure:
- cost control
- reliable planning
- architectural and technical quality
- effective coordination between all project stakeholders
What are standard architectural services?
Standard services are the services that are necessary for an architect to fulfil a missionwithin a construction project.
According to SIA standards, standard services mainly cover:
- the project design phase
- the tendering phase
- the construction phase
They are part of a broader process that begins with the definition of objectives and mayextend through to the operation of the building.
Project phases according to SIA
Phase 1 – Definition of objectives
Establishing the project framework; this is a complementary phase.
This phase defines the basis of the mandate:
- identification of the client’s needs
- definition of project objectives
- selection of the methodological approach
- initial considerations regarding cost, time and quality
Objective: establish a clear framework before design begins.
Phase 2 – Preliminary studies
Assessing feasibility; this is a complementary phase.
During this phase, the architect evaluates:
- regulatory, technical, and economic feasibility
- site conditions and contextual constraints
- definition of the construction project
- selection procedure for consultants and specialists
Objective: confirm that the project is feasible and appropriate.
Phase 3 – Project design
Designing and authorising the building; this is a standard phase.
Preliminary design
- development of the architectural concept
- spatial and volumetric organisation
- initial cost estimation
Detailed design
- further development of the project
- coordination of engineers and specialists
- definition of quality standards
- refined cost estimation
Planning approval procedure
- preparation of the building permit application
- coordination with the authorities
- adaptation of the project to regulatory requirements
Objective: deliver a coherent, controlled, and authorised project.
Phase 4 – Tendering
Preparing for construction; this is a standard phase.
This phase translates the project into construction documents:
- preparation of tender drawings and documents
- specifications and bills of quantities
- analysis and comparison of offers
- recommendation for contract award
Objective: select contractors based on transparent and comparable criteria.
Phase 5 – Construction
Realising the project; this is a standard phase.
Execution design
- detailed execution drawings
- final technical coordination
Construction phase
- architectural site supervision
- coordination of trades and contractors
- monitoring of costs, schedule, and quality
Commissioning and completion
- handover of the building
- follow-up of defects
- final documentation
Objective: deliver a building that meets the agreed objectives.
Phase 6 – Operation
Supporting the building over time; this is a complementary phase.
This phase may be commissioned separately and includes:
- operation of the building
- monitoring and maintenance
- long-term preservation measures
Project management
A central role of the architect
In building projects, overall project management is generally part of the architect’s standard services.
It includes in particular:
- advising the client
- coordinating all project participants
- preparing decision-making documents
- managing information and documentation
- ensuring compliance with objectives related to quality, cost, and schedule
This role guarantees the overall coherence of the project, from initial intent to completion.
Services adapted to every type of project
The architectural services defined by SIA standards apply to all types of projects, including:
- single-family houses
- renovations and refurbishments
- residential buildings
- more complex building types
- renovation or conversion of a building
- energy efficiency improvements to a building
- others
The project phases remain the same; only the scope, duration, and level of coordinationvary depending on the size, complexity, and objectives of the project.
A structured and flexible framework
Standard architectural services according to SIA provide an essential management framework for construction projects in Switzerland.
They offer clarity and structure while remaining flexible and adaptable, allowing architecture firms to support each project with rigour, consistency, and a tailored approach.
A Structured Framework, A Tailored Approach
Understanding standard services under the SIA framework means understanding how aconstruction project is carefully planned, structured, and managed in Switzerland.
Behind each phase lie important decisions, technical and financial considerations, andrigorous coordination.
An architect’s role goes far beyond design — it involves organizing, anticipating, advising,and leading the entire process.
At HertelTan, we see this framework as a solid foundation — never a rigid system.Every project is unique, and our mission is to adapt this structure to your specific needs,objectives, and context.
Building, renovating, or transforming a property is a significant commitment.We support you with method, transparency, and precision — from the initial idea to thecompletion and handover of your building.
Building, renovating, or remodeling is a major undertaking.
We support you with method, transparency, and precision, from the initial concept to the commissioning of your building.
Are you planning a project in Switzerland?
We would be pleased to discuss it with you and explore the next steps together.
