Born in London, Ontario, he spent eight years (1953-1961) studying in Europe after studying at H. B. Beal Secondary School and the University of Western Ontario. While there he met Pablo Picasso, who suggested he continue his studies in Madrid. He called his own work "perceptual realism," a kind of surrealism based on his own dreams and memories and the existentialist philosophy of Maurice Merleau-Ponty. When he returned to London he worked with fellow London native Greg Curnoe. During this period he also made some short films, which influenced his painting (for example, painting on film negatives). In 1969 he was diagnosed with leukemia. For the rest of his life he painted more realistically, often depicting sites in London and the surrounding area. An example of this is Toward London No. 1 (1969), a view of Highway 401 heading westward towards London.
In 1967 he founded Canadian Artists Representation, now a national organization of artists, after an argument with the National Gallery of Canada over reproduction rights and fees.
His work can be seen in the National Gallery, the Art Gallery of Ontario, and Museum London. An elementary school (and the streets surrounding it) are named for him in London, and a tree was planted in his memory in Gibbons Park after his death.
J. K. (Jack) Chambers is also the name of a Canadian linguist, a professor at the University of Toronto who studies, among other things, Canadian English.