In this painting, as is evident, Hopper had yet to develop the clean, almost two dimensional style for which he later became known with his paintings of automats, swimming pools and other features of modern life.
One thing that is very obvious with Mansard Roof, though, is Hopper's fascination with vibrant colours. This use of colour would, as has been mentioned above, later be clarified into a more distinctive style.
In many ways, then, the Mansard Roof painting, which was painted in 1923, contains the seed of Hopper's later works. It is recognisably Hopper's work, though perhaps not at first sight the Hopper who is known throughout the world for his paintings of lonely North American life.
Another interesting feature of this painting is its subject matter. Mansard House is an old Victorian mansion, and at the time, such decaying edifices were thought of as unpopular subjects for paintings.
Hopper's choice of subject matter is itself a break from the norm. This choice of a lonely yet imposing mansion could be said to be foreshadowing the lonely human figures of Hopper's later works.
Even when, as in one of his most famous pictures, Nighthawks, human figures are depicted in groups in Hopper's paintings, they nevertheless are pervaded by a deep sense of loneliness.
In Mansard Roof, Hopper captures this loneliness. This was not the painting that propelled him into the limelight and made his career, but it is definitely a piece in which we see Hopper developing the style that would later make him into one of the most famous and celebrated modern artists in North America