A modernist designer and painter, initially he studied textiles at the Royal College of Art and worked as a designer for Tootal Broadhurst Lee. He began painting in earnest in 1929, before moving to Cornwall in 1930.

Tunnard had his first one man show at The Redfern Gallery in 1933 and exhibited in the Surrealist section of the AIA exhibition in 1937. A retrospective was held at the RA in 1977.