Architect Lawrence D McEwen renovated a kitchen in the Druim Moir house in what had been a conservatory.
Michael and Amy Cohen bought this Colonial, built in the 1920s, in the West Mount Airy section of Philadelphia in 2011.
This light fixture, designed by Design Nehez to maximize the stairwell in the Cohen house, is made of glass blown at a local studio in Philadelphia.
A custom-made living room rug, also by Design Nehez, echoes the shapes and drips of a painting Mr. Cohen made in preschool and matches the Coca-Cola red sofa.
Architect Alan Metcalfe of Metcalfe Architecture & Design worked with McCoubrey/Overholser to create a contemporary interior, including more open rooms.
The half wall that separates the two rooms doubles as a 'found art' installation project, with multicolored plastic bread tags imbedded in a large pane of clear plexiglass. There is a tab with the birth date of each member of the Cohen family. 
"Brick and stone says 'home' to me. But I really like modern design. I never thought that exterior and interior had to agree," says Ms. Cohen, a high school and middle school social studies teacher.
Amy and Michael Cohen are pictured in the dining room of their house while their daughters Eliza, center, 15, and Chloe, right, 11, are in the kitchen, along with Genesis Polo, 15, an exchange student from Mexico.
Philadelphia artist Joan Wadleigh Curran turned three internally connected 19th-century carriage houses in the heart of Philadelphia's downtown into a 4,300-square-foot three bedroom home.
Ms. Wadleigh Curran focused on keeping original details like the brick walls and unsealed concrete but added other natural materials like steel beams and an open, steel staircase to give it what she calls an 'unfinished look.' 
'The building has a feel of history to it. It's like life—there's a history to things but there's also the new. I wanted to keep that juxtaposition,' says Ms. Wadleigh Curran.
The home is also filled with colors, mostly from the blues, yellows, reds and greens of the walls and her own tree-filled paintings.
Peter and Mari Shaw renovated their 1880s house that was designed by celebrated Victorian-era Philadelphia architect Frank Furness and has 13-foot ceilings on the first floor. It had been converted into doctors' offices. The Shaws restored all the old moldings and refinished the original floors. 
The Shaws combined their contemporary art collection with modern furniture, including these Mies van der Rohe Barcelona chairs, shown here
Looking down the stairs from the second floor to the first floor in the Shaws' house. The couple restored the home's original moldings.
The rear master bedroom on the second floor of the Shaws' house.
The front living room on the third floor of the Shaws' house. Shown here is a piece by Philadelphia artist Stuart Netsky titled 'Seurat's La Grande Jatte(Detail),' 1998.
Ms. Shaw, a former senior partner in a law firm who is currently a writer, and Mr. Shaw, a real-estate developer, pose in the first floor front parlor in front of a sculpture by Rachael Harrison titled 'Day's Grape,' 2002
This home in Reading, Pa. was designed by James W. Rowe, a principal of Studio Agoos Lovera. Mr. Rowe incorporated an existing farmhouse to create a 7,000-square-foot contemporary home on 120 acres.
Owner T.J. McGlinn, who grew up next door, says he didn't have it in his heart to tear the farmhouse down--but he wanted a more modern, contemporary interior.
Built in 1800, Hank McNeil's Neo-Georgian 13,000-square-foot Rittenhouse Square mansion is red brick and cube-shaped, with rectangular double-hung windows all aligned and a red front door flanked by Corinthian columns. When Mr. McNeil bought it the interior rooms had been converted into law offices.
Now, the interior is highly contemporary, and filled with one of the leading collections of minimalist modern art in the country.
The first floor front dining room of Mr. McNeil's house. Since he couldn't touch the exterior due to historical regulations, Mr. McNeil turned his attention inside, knocking down walls to create three rooms on the main floor. 
The second floor display room of Mr. McNeil's house. 
Mr. McNeil installed glass doors and skylights in the house and modern Bulthaup cabinets in the open kitchen. He is shown here with girlfriend Emily Morgan.
Mr. McNeil's son Cole McNeil shoots some hoops on the fourth floor of his father's house.
Mr. McNeil, Emily Morgan and Mr. McNeil's two kids, from left, Calder and Cole, pose for a portrait in their second floor living room.
Michael Ryan, of Michael Ryan Architects, designed the renovation of this barn in a suburb of Philadelphia. Mr. Ryan says there is a type of architecture that speaks to the past, without being related to a specific style and this generally is found in buildings that were constructed to serve a function without any high aspiration, such as a barn.
The interior of the barn, now designed in a contemporary style, with old stone walls and 22-foot ceilings, was derelict when the owners bought it and had no foundation.
It took art curator Eileen Tognini, 52, about 25 years—and her daughter moving out to go to college—before she and her husband Tony finally turned the interior of their three-story, 2,500-square-foot Victorian 1882 brownstone in what's called the Fishtown neighborhood of Philadelphia into the contemporary design they'd long wanted.
Ms. Tognini, an independent art curator, filled the home with contemporary art mostly by local artists, such as the wood sculpture, at right, made by Alison Stigora.
The kitchen of the house has double-panel cabinet doors made from laser-cut steel that feature an abstract design modeled after a historic map of the neighborhood.
The photographs hanging above the bed in the master bedroom are by Japanese-born photographer Hiroshi Watanabe.
The steel and glass staircase has a light sculpture by Warren Muller that includes steel rods and old trumpets, toy train tracks and parts of old pistons.
Eileen, sitting, and Tony Tognini are pictured with their daughter Isabella, 19.
