From 1967 until 1971 he trained as a metalworker; from 1969 until 1970 he went to Italy and the former Yugoslavia on a study trip. In 1970 he worked in a studio in a galvanizing company where he received impetus for his artistic creation. From 1972 until 1974 a studio at Stift Rein employed him. There he carried out restorations and started with his own silver and gold jewellery.
In 1973, Krenn exhibited at Grazer Kunsthandlung and at Galerie Moser where he exhibited surreal oil paintings. In 1979 he participated in the Expansion project in the city gardens Vienna (Stadtpark). In the same year he was part of the steirischer herbst festival with is Waldaktion (forest action project) and in 1983 he also participated with Zeitrasterkäfig in this festival. In 1985 the artist was to be seen in Park Avenue, New York and 1990 at the Grazer Hauptplatz/main square. In 1992 his art train was presented at Graz Ostbahnhof station. This train is a goods wagon with a 13 metre-long steel cage holding foundlings and plants.
Othmar Krenn was active as a painter, actionist, draftsman and sculptor. Monumental but equally elegant sculptures made of metal and stone became his trademark. For the trained metal worker, the use of material such as stone and metal symbolises the problematic intervention of human civilisation in nature. Stone, which is the symbol for untouched nature, is wrapped and enclosed with metal. The artist calls his works “world models” since he wants them to transmit meanings that contribute to the interpretation of the world.
The actionist Othmar Krenn tries to realise his understanding of spirituality in severe contrasts. In various different actions Krenn went to the limits: he lived in earth caves, let himself be carted through New York and Graz in a cage, with a crane swayed from the roofs of high rise buildings, but himself under electric power or pulled ropes through eyelets in his ears. In his very private Yanktopis cult, for which he created a museum-like centre in his studio and house (a former brick factory) and created a central “work in progress”: the re-construction of his own skeleton in rocket steel.
In 1995 the church St Lukas at Graz Eggenberger Guertel was inaugurated. Othmar Krenn had planned and re-designed this church meticulously and it illustrates the broad creativity of this artist. In 1996 on the occasion of “Whitsun of artists” he exhibited at St. Lukas church. In April 1998 Othmar Krenn died in a car crash.