Born in 1966 in Karl-Marx-Stadt (today again Chemnitz). Training as plaster of Paris worker in Leipzig and Berlin; afterwards, as stage technician at the Städtisches Theater in Karl-Marx-Stadt. In 1990 he designed his first stage set for a production by Hasko Weber. Works since 1993, with an interlude at Frank Castorf's Berlin Volksbühne, in Chemnitz. Here Altmann became acquainted with the directors Martin Nimz and Michael Thalheimer, with whom he still collaborates. He has formed a team with Thalheimer since their first production: at, for instance, the Theater Basel, the Staatsschauspiel Dresden, the Schauspiel Leipzig and, in recent years, above all the Thalia Theater Hamburg and the Deutsches Theater Berlin.
In 2001, two of Thalheimer's productions with sets by Altmann were invited for the first time to the Berliner Theatertreffen: Liliom
(Hamburg, awarded the 3sat-Prize for Innovation) and Das Fest
(i.e., The Celebration, Dresden); in 2004 Lulu
(Hamburg) followed. At the Deutsches Theater, they together produced the world success Emilia Galotti
(2001) and both parts of Goethe's Faust
(2004/05). Altmann, who also works with the directors Martin Kušej and Dušan David Parizek, is also a costume designer and himself a director. In Kassel, Dresden and Cologne, he has produced plays by Fassbinder, Camus and Fosse.