Think for a moment of your typical home for a young family. Chances are a 1914 Craftsman—painstakingly restored to its original splendor, from the wall trim down to the lighting fixtures—wasn’t the first image that popped into your head, but that’s just what made one Berkeley, California , project so appealing to Los Angeles designer Frances Merrill, principal of Reath Design .

“The previous owners had done a remodel that was very faithful to the era,” she says. “Every detail was really beautifully done. But it was sort of serious for a young family; it could look imposing and formal. The goal became figuring out how to make it lighter without changing the look of the house.”

A vintage settee, antique rugs, a Blue Dot side table, and a custom chandelier lighten the mood in the house’s entry.

Merrill began by researching a spectrum of Craftsman homes to see which characteristics were most conducive to playful intervention, finding that the aesthetic was surprisingly flexible so long as a handmade feel was visible throughout. She swapped out the lighting fixtures’ heavy yellow casings for airier clear-glass custom models, adding green-hued detailing to introduce a more colorful palette; repainted the second-level trim to match; and retiled the living room’s fireplace with livelier Heath ceramic tiles. “When you go into a home that’s so perfect for the era, you don’t want to make it wrong,” says Merrill. “We tried to tell a story and create a mood that stayed true but was just a little fresher.” Reupholstered furniture pieces, window treatments, and vintage rugs in a variety of textures and patterns, from Liberty of London to William Morris, give the house a bohemian feel that isn’t representative of any one time period. In the basement alone, Merrill and her team sewed together 20 antique rugs from Lawrence of La Brea to break up the space.

But perhaps the most impactful move to add life and personality to the space came with the unorthodox application of wallpaper throughout the home. Merrill plastered whimsical patterns by the likes of Tafet Café and Trustworth in a series of unexpected places—in a windowed nook in the attic playroom, above the picture-rail trim in the nursery and dining room—to create the kind of imaginative flourish that children particularly appreciate. “The clients wanted to create a home where their family would grow and make memories,” says Merrill. “The space you live in affects your experience of the world. When you grow up in a place that feels magical, that stays with you.”