Kitchen design used to be simple: It was all about the work triangle, allowing the cook to move efficiently from refrigerator to range to sink.
Now, though, designers have more complex calculations to make. After all, the work triangle never accounted for the second island, the extra prep sink, or the double oven - or where to situate the love seat, fireplace, tablet-docking station, and flat-screen television.
"It's quite a revolutionary time in kitchens," Philadelphia kitchen designer Joanne Hudson said.
Kitchens have grown by about 50 percent over the past 40 years, according to the National Home Builders Association.
Now, at an average 306 square feet, they take up 11.6 percent of the floor plan in a typical new house. In older houses, they're devouring dining rooms, home offices and dens to keep up.
The manifest destiny of the kitchen, it appears, is to become a multipurpose great room for living, eating, entertaining, and, from time to time, cooking.
"What we're seeing is a trend in general toward larger kitchens but smaller houses," said Richard Buchanan of Archer & Buchanan Architecture in West Chester.
"Forty years ago, a kitchen had Formica countertops, a Kenmore refrigerator with magnets on it, and a stove you bought at Sears. Now, in our projects, $5,000 ranges are rather common, and large Sub-Zero refrigerators and freezers are a status symbol. It's sort of, the Mercedes is moving into the kitchen."
Buchanan said that shift is pegged to the evolution of people's lifestyles over the last century.
Kitchens, he noted, began as humble workspaces, the domain of servants.
Even after household staff disappeared, the kitchen remained segregated as architects distinguished between informal and formal living spaces: kitchen and dining room, family room and living room.
But as people adopted more casual lifestyles, he noted, those spaces began to merge.
"Now, the kitchen is probably the main feature in the house, with access to the outdoors and to the living room, great room and dining room," Hudson said.
She cited a second force behind that shift: the emergence of food culture, powered by the Food Network and its ilk. Even if not all of us cook, most of us these days like the idea of cooking.
Hudson has had calls for wood-burning pizza ovens, built-in espresso machines, walk-in refrigerators, and multiple large wine coolers, among many other customized details.
In other cases, the kitchen and living spaces are simply combined. Hudson did a number of kitchens in the tony 1706 Rittenhouse condo building; most of them featured contiguous cooking, living and dining spaces.
Architects are starting to take notice: Hudson said these days she's getting called in much earlier in the design process.
Still, Paul McAlary of Main Line Kitchen Design said that most large homebuilders haven't caught up quickly enough.
He said about 50 percent of the jobs he does - and nearly all of the jobs he does for clients younger than 40 - involve tearing down the wall between kitchen and dining room to make one large kitchen.