About us

We are a Helsinki-based architecture and design agency. We are working on architecture in a variety of scales, but residential design and exhibition design are our specialities. So houses and working with museums and other institutions, to say it in other words.

Tuomas Siitonen has a M.Sc. in Architecture from Helsinki University of Technology and M.A. from the Graphic Design department of Helsinki University of Art and Design. Combining these skills in actual projects since around 2001 Tuomas launched Tuomas Siitonen Office in 2010.

Since then our small and flexible team has worked on projects for public and private clients. Our public clients include The National Museum of Finland, HAM Helsinki City Art Museum and Design Museum in Helsinki. For private clients we have designed a number of houses and smaller dwellings, often on demanding sites in urban context. View the client list.

The work of Tuomas Siitonen has been exhibited in various occasions, including the Biennial Survey of Finnish Architecture and the Venice Biennale. It has also been featured by Dezeen, Dwell, ArchDaily and others. Links to selected articles.

In addition to running the office Tuomas Siitonen has a teaching position in the Department of Architecture, chair of Architectural Principles and Theory of Aalto University and does visiting lectures and workshops on a regular basis. In 2018 he got the Teacher of the Year -award from the students of architecture in Aalto University.

Launched in 2019, our exhibition design projects are carried out through Kombo, a new partnership of skilled exhibition designers.


Photo by Tuomas Uusheimo

Our services

Concept design
Architectural design
Construction drawings and documents
Building site supervision
Bureaucracy handling
Project management

Our tools

We utilize latest computer tools, including cloud-based project sharing and BIM modeling. Besides these we employ traditional methods like physical scale models.

Our team

Tuomas Siitonen, architect SAFA GRAFIA, director
Antti Auvinen, project architect
Monica Romagnoli, interior architect

Johannes Nieminen / Besserwisser.fi,
graphic design collaborator
Panu Heikkilä / Fantomatico.org,
interactive design collaborator