A few years back, designer Summer Thornton noticed some exciting developments coming from across the pond—the U.K., to be exact. So, she hopped on a plane. She and her team visited stalwarts like Sir John Soane’s Museum and the V&A, stayed in a Kit Kemp hotel, and checked out Annabel’s (a personal highlight). “We came back, and our joke was no more white,” she laughs. As luck would have it, Thornton was starting a project with her “design soul sister”—a client with a love for homey spaces, who wanted to bring some color and pattern into her life.

The client was embarking on a next-phase renovation of her 1896 abode. Some 15 years before, she and her husband had purchased the place and called on architects Jeff Harting and John Toniolo to renovate. “A lot of people had lived there, and everyone had done something to it,” the wife recalls. “The living room had Roman columns and a dropped ceiling with fluorescent lighting, there was a Southwest motif in the family room and the kitchen was encased in a glass cage.” Harting says he and Toniolo “approached the structure as a blank slate, gutting the interior and restoring the historic shell.” Adding a bit of splendor, they opened rooms to one another, installed large, cased openings, recreated the staircase and crafted “bigger, more voluptuous” moldings and millwork.

Three children later, the owners turned to Harting and Toniolo once again. The plan was to keep much of the past renovation intact but make a few changes based on their current lifestyle. An expanded mudroom accommodates the gear a family of five accumulates. In the kitchen, a few savvy moves made the space seem larger, although the square footage stayed the same. New cabinets and crown moldings run up to the ceiling, giving the illusion of greater height. Removing a nook made things feel more spacious, while widening the opening between the kitchen and the family room enhanced the connection between the two spaces. “They’re still separate,” says the wife, “but they talk to each other better.” Finally, the architects crafted an sun room addition that serves as a study. “We did a skylight, so it’s lighter and airier than the main structure,” explains Harting. “It feels like a conservatory.”

It wasn’t just the family’s functional needs that had evolved. “When we first did the house, I was going to be a new mom, so it was quiet, neutral, soothing with lots of sisal, texture and art versus color,” says the client. “Now I wanted it to be fun, eclectic and cool.” Enter Thornton. “Summer can mix things, and they just work. Sometimes I don’t think she’s consciously doing it. It’s just part of her natural process,” the client explains, pointing to the blue-and-white wallcovering in a tight pattern in her bedroom. The design plays off the blue floral print visible in the bathroom. Nearby, in the dressing room, is “a complete Madeleine Castaing moment,” says Thornton—complete with wallpaper and a vanity chair in gold coverings festooned with ribbons, feathers and bouquets of flowers. “It’s so tiny it doesn’t seem ostentatious,” says the designer. “There’s a 1940s glamour to it.”

Thornton’s skill in tying pattern and color together is perhaps clearest in the family room and study. “Because the family room is a connection point, we wanted the main portions to feel neutral, so the walls are white and we made bigger statements in the upholstery,” she says. There’s a tiger-print couch—a request from the client who admired one Thornton had in her office—a sofa in goldenrod and a plum-toned rug. The blue and gold hues (the client’s favorite colors) link the space to the new study, which sports a wallcovering of deep blue, hand-applied burlap. “It ties the room together and gives it a textural depth,” says Thornton. “I like a darker endpoint to draw you in the space. It’s a bold statement that, when paired correctly, feels effortless.”

Working with the client resonated with Thornton beyond just their shared aesthetic sensibility. “We were making this nostalgic family home, and that’s something I wanted to put in my own home as well,” she says. “She set me on the path of creating these charming, rambling family spaces full of joy and life.”