Her painting is characterized by individual, square brush strokes with bright unblended colours. Her many paintings of Sydney landscapes, still-lifes, and interiors include "Kuringai Avenue" (1943), "Fruit in the Window" (1957), and, arguably her most famous painting, "The Lacquer Room" (1935). She received acclaim late in her career, and in 1973 a major retrospective exhibition of her work toured Australia.
She used great sunlight and wonderful patterns of vibrant colour with cool colours added to shadows, giving them a sense of energy. Using carefully placed brush strokes of brilliant colour side by side to build up small squares, she built form in colour. She was one of the earliest Australian artists to be influenced by the European Post-Impressionist movement and lead a break away from Australian Impressionism. A contemporary of Margaret Preston, her works were very daring for the time. Her main interest was colour, bright shimmering colour filled with reflected sunlight. She supported modernism and developed her own individual technique.
She grew up in her family's first house, "Cossington" in Neutral Bay. She lived in a house in Ku-Ring-Gai Avenue, Turramurra, Sydney for most of her life, which was also called "Cossington". Both houses were named after her mother's house, Cossington Hall in Leicestershire, England, which was also her middle name. Grace attended the girls' private school, Abbotsleigh School for Girls in Wahroonga.
Her best known modernist painting is The Lacquer Room, 1935-36, showing a view across an Art Deco styled cafe called the Soda Fountain, which was then located in the David Jones department store in Sydney. The work itself is highly stylised, with pinks, yellows and blues on the walls and on the floor. The people depicted have little detail shown in their faces, though in what is shown they look obviously surprised and somewhat condescending in their glance towards the viewer. The vibrant glaring colours reflect modern style. The painting is notable for its absence of shadow; the walls are glowing with bright non-directional light and colour. Everything about the painting seems modern, from trendy green table tops to pinkish and red colours on the chairs and on the walls. Two unusual yellow modern style lamps on the walls have an Art Deco look. The customers wear fur coats with stylish hats, giving an impression that this is a place for well-to-do people though people did dress more formally to go to town in those days. The waitresses wear a bright green colour in keeping with the rest. The chairs have huge backs and tiny legs, reflecting a new modern world of manufactured objects, rather than traditional wooden furniture.
Smith's paintings included arrangements of flowers consisting of daffodils, hippeastrums and Waratahs. As part of her personal oeuvre, she painted a work of a dog sleeping called Krinkley Kronks Sleeping in cool purples and oranges, although Rex was the name of the actual dog.
Her paintings of the Sydney Harbour Bridge as it was being built are some of the best painted at the turn of the century when it was a symbol of what the people of Australia are capable of. Her first paintings of the harbour bridge such as The Curve of the Bridge, were of the bridge before the actual work on the arms had started, and to disguise this fact she concentrated more on painting the pylons in her earlier paintings of the bridge. She painted the arches as they were approaching one another, liking the tension between the two sides, and did not paint the bridge after it was completed. Though the painting The Bridge in Curve was rejected from the Society of Artists exhibition in 1930 it is now considered one of Australia's best modernist paintings. It shows the construction work continuing, with cranes fixed over the edges of both sides of the bridge. Her highly detailed drawn study for the painting shows her eye for details and her ability to capture a scene in a photo-realistic manner. Smith did in fact draw the Harbour Bridge completed in Great White Ship at Circular Quay, but here as the title suggests, the focus is more upon the ship in the foreground than the bridge itself.
She painted outdoor scenes, somewhat less successfully than her indoor scenes, but painted outside whenever someone could take her out in the countryside to paint, going on many trips. In her life she visited several towns outside Sydney, as well as visiting the national capital, Canberra. She also painted in the Blue Mountains, and in Moss Vale and Exeter. Beginning in the late 1930s, she started a style which was less influenced by the modernist one, and more to do with the light and colour of Australia, and her own personal interpretation of the landscape. Her paintings show the olive green and sienna colours of the Australian bush, depicted in a style where the brush strokes are visible, made up of many similar colours. One of her best landscapes was a series of four large paintings she did called Four panels for a screen: loquat tree, gum and wattle trees, waterfall, picnic in the gully#, 1929. The first two panels show the trees in her yard, while the last two show the world further away from her home; a waterfall and people having a picnic with a billy can in a gully. It symbolises the theme and division in her landscape work between her immediate streets and trees, and further away from her home, where her friends and relatives often took her to paint. The four paintings were done on commission, however the commission was refused and because of this Grace would never work on a large commission again.
She visited England once with her sister between 1912 and 1914, and returned to Europe later, between 1948 and 1951. On her overseas trips, Grace experienced a world different from her own, yet in her paintings gave it her own unique style. On the second trip she became very interested in English architecture and, besides sketches and drawings of cathedrals and buildings, took many photos of indoor doorways and scenes of rooms inside houses. Her many sketchbooks reveal something of her life - being more loose and personal than larger paintings, sketchbooks can give more of an insight into the details of the artist's everyday life.
Smith's indoor views show the pleasant aspects of a suburban home in Sydney in the 1950s and 1960s. In these works, her love of the colour yellow is most obvious. She loved the colour because it is the colour of the sun, as well as being religiously significant because yellow is a colour of glory. She also regarded yellow as the colour of the Australian bush, rather than other painters at the time who tended to see the Australian countryside as being more reddish than yellowish. Her paintings explore the perspective, shapes and colours of objects inside seemingly ordinary rooms. They offer a vision of the type of furniture, clothing and other objects which suburban people had in their homes during this time. Drapery, chair and window, 1942 shows what seems at first to be merely a couple of chairs in front of a window, but the viewer is drawn into the wonderful spaces created around these delightful objects, and the folds of the drapery which create a lovely feeling of light and shadows.
Increasingly she would concentrate on these interior views, with ten room paintings exhibited in her solo exhibition of 1947. Her large oil, Interior with verandah doors of 1954, shows an accurate depiction of her house with a large window and a door opening to the outside on the other side of the bed. The painting is the first of her larger room interior paintings and prominently features yellow in the colouring. She also experimented with views in mirrors, such as in Interior with wardrobe mirror, 1955, which shows a mirror on an open wardrobe door that is opened at a 45 degree angle, whereby the viewer is given a view of the yard outside the house from the reflection in the glass. The angular cutting into the basic composition with these doors adds dynamism and gives it an energetic feel.
In all her later paintings she used a unique style of squarish daubs of paint applied on the canvas, in colours which were varied but which tended towards the yellow end of the spectrum. Many of her room interior paintings show the same room from different angles, or even multiple views from a slightly different or the same angle. In some paintings a door or window is the dominant focus for the painting, while in others the viewer is shown the entire room. Her use of colour has been compared to the work of Pierre Bonnard, though she said she found Cezanne a more important influence on her. Her style of many multi-coloured brush strokes was used not only in her interior views, but also in her still lives.
Smith's later still lifes are works that explore the use of different colours put together to give a unifying feel. She painted many still lifes of fruit, jugs and vases with glimpses of drapery and parts of the room behind. In style, they consisted of many individual, choppy, squarish brush strokes making up the whole, varied in colour, but still giving an overall yellowish feel. She has a striking sense of perspective, and great eye for detail, planting the objects firmly in three dimensional space. Still life with red vase, 1962, shows a bold red vase contrasted with the background made from its complementary opposite colour, green, or at least, greenish-yellow. Another jug to the right blends in with the background, while the red jug is firmly planted in the perspective of the table. Still life with white cup and saucer, 1971, one of her last paintings, shows several jugs, green, red and yellow, all given a sense of being very solid objects, with a delightful white cup and saucer nearby. She was very frail after this, being unable to paint any more large works.