When Toby Young bought her one-bedroom apartment in New York’s Gramercy Park neighborhood, she knew she would have very little money to renovate the kitchen. She planned to simply paint the dark brown cabinets white, replace the ceiling light and update the cabinet hardware to chrome to match the existing faucet. It was this last item on her to-do list that confused her; her small kitchen opened directly onto her living/dining room, in which all the hardware — doorknobs, hinges and lighting — was brass. “I had always been taught that, like the color of my shoes, belt and handbag, the metal hardware in a room should match.” Lucky for Young, times have changed. Restrictive rules about matching fashion accessories are no more and, to a degree (a few guidelines do apply), the same can be said about mixing metal hardware finishes in homes.

Mixing metal finishes is a conscious design choice for New York designer Thomas O’Brien, founder of Aero Studios, and one he even made for his own residence. When he renovated the kitchen in his Bellport, N.Y., home, he painted his cabinets a glossy white and installed satin brass handles, but he opted to use chrome for all the plumbing fixtures. He says that when mixing metals in a room, there should be logic behind each choice. “For example, I chose the brass handles because I wanted a softer and warmer feeling than chrome.” He considers kitchen cabinets to be like furniture, so in his mind, they can be treated differently.

D.C. interior designer Zoe Feldman is also in favor of mixing metal hardware finishes. “I feel it keeps a space from feeling too one-note, and it gives a more collected and layered look,” Feldman says. In general, she avoids using any kind of matching sets in her work, such as a dining or bedroom set, because she says sets are too predictable; she sees matching metal hardware the same way, and says it has a boring, uninspired effect on rooms.

But one can’t just go mixing any and all metal hardware finishes together. Both O’Brien and Feldman agree that there are some guidelines one should follow. O’Brien suggests mixing brass and dark bronze, brass and chrome, or brass and nickel, but he says to never mix nickel and chrome. Also, he cautions that there is a limit to how many metal finishes you can mix together in one room. “There should be a main finish choice and maybe one accent,” he says. More than that, he says, can be too much. And for those who worry about how their stainless-steel appliances fit in with other metals, O’Brien says: “Chrome and stainless steel are really the same and can be used together.”

Feldman says she usually sticks to a maximum of three metals in a room. She also pays attention to the placement of each finish. “You want to make sure there is a certain cadence when mixing metal finishes,” she says. By cadence, Feldman means that you should consistently disperse the metal types throughout the room; all pulls and knobs should be one type, and all fixtures (such as sink and bathroom faucets) should be one type. Feldman says lighting is a good place to introduce yet another metal type, as are accessories such as pot racks in kitchens or door hooks in bathrooms.

Aside from mixing metal colors, Feldman also says to pay attention to finishes. She likes to mix metals of different colors but that share a similar warmth, such as unlacquered brass, polished nickel and matte black, but she says to never mix the same metal in different finishes, such as polished nickel and satin nickel. Like O’Brien, she says to not mix metals that are closely related but just a bit off, such as nickel and chrome. “They are too similar to be interesting,” she says. “One is the cool version and the other is the warm version.”

When possible, Feldman likes to use what she calls “live metals,” which are metals that are unlacquered. “I love the idea of metals aging and getting a patina,” she says. “It gives a space depth and allows the fixtures to age gracefully.”

As for Young, she decided to leave the existing chrome fixtures, install antique brass cabinet pulls and hang an antique brass and dark bronze ceiling fixture that unites all the finishes. “The light fixture ties it all together,” Young says. “It’s just like jewelry. When you wear a stainless-steel and gold watch, you can wear silver or gold, or both.”

Mayhew, a “Today” show style expert and former magazine editor, is the author of “Flip! for Decorating.”

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