Redpath was born in Galashiels and studied at Edinburgh College of Art. In 1920 she married and moved to France, devoting much of the next fourteen years to her family and doing little painting. In the mid-1930s she returned to Scotland, settling in Hawick in the Borders. Redpath admired the French Post-Impressionist artists, such as Van Gogh and Gauguin, and also Matisse. From the 1950s, she became well known in the Scottish art world, specialising in landscapes, church interiors and still lifes painted in rich colours.
Her work from the late 1950s responds to Abstract Expressionism in the free and expressive handling of paint. Her work can be seen at the Royal Academy, Tate Gallery and the Scottish National Gallery of Modern Art.