TODAY, PEOPLE who live in rowhouses don't have cooks, they are cooks. Somehow it seems to be a truism that an interest in fancy cooking goes along with the type of person who wants to remodel a row house and live on Dupont Circle.

Almost all old Victorian rowhouses originally had the kitchens, and often the servants' dining room (or the family sitting room), in what's locally called the "English" basement. The cook and the groceries had their own street entrance and exit to the trash cans. In the summer, the basements were cool despite the wood cook stove. In the winter, the rooms were cozy, often the only warm rooms in the house.

A dumbwaiter from the basement to the first floor served the formal dining and drawing room. This wasn't such a problem, because you had a cook in the kitchen and a butler or a serving maid on the second floor.

Basements have come down in the world since then. No cooks, only renters, will live like trolls in a basement. Everybody makes a rental apartment out of the basement because how else can you pay the mortgage and the taxes?

So the first thing most people do when they move into a rowhouse is build a new kitchen.

How two pairs of Dupont Circle owners coped with the problem is instructive. One pair went professional -- architect, builder, top-of-the-line appliances -- a magnificent, spacious working kitchen in a bright contemporary style in keeping with their early Scandinavian furniture.

The other owners did all the design and work themselves, restricting themselves to a tiny space where the pantry once was, scavenging equipment from the alley and friends, using their collections of Victorian glassware and china. The result is charming, though, as the owner says, "only big enough for one person and one cat." And the kitchen is just right with the couple's splendid collection of Victorian furniture and objets dArt.

Both kitchens, as well as houses to which they're attached, plus nine other Dupont Circle houses will be on tour today (see story on this page). We took a sampler preview tour. The Professional Way

When Charlotte Jones comes home, she takes her shoes off for the pleasure of walking on the wonderful uneven Mexican tile floor. The tiles have humps and dips, because they're handmade and sundried. The variation is part of the charm. Besides, you get a foot massage as you walk around.

(The tiles came from the Tile Gallery, 803 Potomac St., and were laid by Jim Ransom.)

Jones and her husband, Thomas Carroll, bought their house (for just under $200,000) in the 1700 block of Q Street in 1978. The house is one of the original Thomas Franklin Schneider houses built in 1891. Rabbi Harold White had remodeled the house recently.

The couple are very much interested in cooking, and the tiny butler's pantry converted to a kitchen was not big enough for both, plus Mercedes Enutan, their housekeeper.

They hired Don Hawkins, who had designed a house for Carroll in the country. His associate at the time, Harlan Hadley, took charge of the project. William Newberry was the contractor for Carrol and also on the Perle house (see story page 1). The project was finished in June. The remodeling cost about $40,000, with another $8,000 for the deck and patio.

The kitchen design, which promises good, fresh food with plenty of jalapanos, was influenced by the Carrolls' interest in contemporary design and Latin American crafts. Jones is the loan officer for Equador with the World Bank. Carroll is senior adviser with the Inter-American Development Bank. Both have lived in Central and South America. Carroll also had a fine collection of 1950s Scandinavian furniture. He moved from a contemporary house with a half acre and a swimming pool in Bethesda.

The old back porch went first. In its place, they built a one-story, slant-ceiling L-shaped addition, with tall glass doors to a south deck and brick patio, shaded by a huge, double-trunk magnolia that may be one of the oldest in town. In keeping with today's belief that kitchens are not shameful rooms that have to be hidden, arched doorways (where the windows once were) open the kitchen to the dining room and the hall. A closet and powder room now occupy the space of the old kitchen.

On the west end, on the way to the patio, the addition is a pleasant breakfast room with a bank of skylights and track lighting. "We wanted it to be as light as possible," said Jones, "because we were losing the windows into the dining room."

In the breakfast area are a glass table and Marcel Breuer cane chairs.

On the east, it's all kitchen. A professional Chambers gas cooktop is built in. It has a center broiler that can also be a griddle ($600-$700). "I like it because the burners don't wobble," said Carroll. A Thermodor micro-wave/normal oven combination is built to the side (but below). "It'll zap a baked patato in 20 minutes," Carroll said.

The cabinets, though they look custom, are really standard pecan cabinets from Miller's Kitchens. The counter tops are butcher block with Mexican tiles for emphasis. They chose the Sub-Zero refrigerator, Carroll said, because it's only 24 inches deep. Its doors are covered with the same pecan wood as the cabinets.

Between the kitchen and the informal dining room is a bar with a stool for buffet serving, augmented by a teak buffet.

A bit of leftover space, made by the arched opening into the dining room, provides a floor-to-ceiling built-in display space for the Jone's collection of baskets and pottery. Other pottery and some masks hang on the brick wall over the buffet.

Where the old basement kitchen once was, the Carrolls made a rental unit. General Heating installed the apartment's independent gas heating unit, and a second one for their first floor, and added two heat pumps for the upstairs floors. This way visible ducts were only necessary on the top floor. It took a crane to lift the condensers on to the roof. (Their air-conditioning bill in August was $211, even so.) Since they had to put in a foundation for the kitchen/breakfast room addition anyway, the Carrolls added a storage room beneath it.

The living room and dining room both have pieces from Carrolls's collection of Danish furniture, bought in Denmark in the 1950s when it was first produced. From the want ads, Carroll bought a great oak roll-top desk, with the most drawers I've ever seen. It occupies a prominent place in the living room. along with the Danish leather chairs. The matching living and dining room chandeliers came with the house.

On the next floor is a suite for Carroll's son, now away at Cornell, and 1,000 square feet of tongue-and-groove joint cherry paneling, bought again from the want ads. Carroll plans to panel the second floor sitting room with it.

On the top floor, Carroll and Jones have a sybaritic master bedroom, with their large bed occupying a platform in front of the fireplace. The bedspread is Hungarian handwork, a heirloom from Carroll's mother. The north wall opens onto a small balcony. On either side are leaded glass windows from an old Pennsylvania house. The new closets use modling from another house. "There was only one-and-a-half closets in the whole house when we bought it," said Jones.

As we left, we admired the contemporary sunburst stained-glass window, a wedding present from Paula Cruz, a glass artist who plans to settle in Washington. Talented Scavengers

Around the corner on Church Street, Bob Lewis, an illustrator with the Smithsonian's Natural History Museum, and Bill Ryan, a curator at the Phillips Collection, have a 1893 rowhouse that cost them a little more than a tenth the price of the Q Street house. Their Church Street house is narrower and more modest than the Carrolls', but the main difference in price is when the two houses were bought. Ryan and Lewis bought theirs in 1971, so houses in the area have increased just about 10 times in not quite 10 years.

Lewis and Ryan have done most of the work on the house themselves, and thanks to their talents as scavengers, have been able to keep the house close to its original Victorian taste.

We walked in past an exuberant gold-leaf pier mirror, and through a living room and dining room overstuffed with Victoriana. "We had a lot of things," said Lewis. "And then I was willed more Victorian furniture. I console myself by thinking that a bit of crowding is appropriate to the interior design of the period."

Lewis and Ryan, faced with the usual basement kitchen, did the traditional thing and made a guest apartment in it. Upstairs, where the doors to the back hall, the dumbwaiter and the butler's pantry all knocked into each other, they made a tiny but very efficient pleasant kitchen.

They opened up the wall between the dining room and kitchen, leaving a half wall as a screen and a place from which to serve. Lewis, who's the carpenter, built the counter using old mouldings. The upper cabinets are compounded from old shutter doors and glass-front bookcases. The tiles above the sink are 17th and 18th century, a present from someone who knew their taste. The wonderful brass facets on the sink "I found at Jenks hardware before they moved. I'm sure they are old ones that had been forgotten," Lewis said.

The refrigerator is a double-door under-the-counter Sanyo. "I'm sure it's about to die, and then where will I find one that fits?" mourned Lewis.

The refrigerator is topped with a marble slab from a fireplace, bought at a Capital Hill salvage yard. The sink itself, a traditional old procelain one with drainboard, came from the original sink in the basement.

One wall is shelves to hold staples. The floor tiles, a square and diamond pattern, came from a church. The antlers on the wall were left in the house by a previous tenant.

In the adjacent rooms, Lewis exercised more of his talents for scrounging. The two ornate fireplaces came from what Lewis said was "the only house torn down on Hillyer Place." They don't use the fireplace in the dining room anymore since "we lit it, and smoke came out of the window sash." They do run the furnace's fan during the summer, enabling them to do without air conditioning and have a $90 electric bill in August. The brass door fixtures through the house were presents from other people on the block.

Downstairs, in the apartment, the kitchen is not much bigger. The cabinet was "thrown out when they remodeled Cavanaugh Court apartments," said Lewis. wThe marble tiles from Hechinger's considerably upgrade the counter. A half glass pub door from the late Joyous Junque makes a division between the sitting room and the kitchen area.

Lewis made an alcove for the sink by recessing it into the wall of an adjacent closet. The closets are on either side of a built-in seat, ornamented with brackets bought at Elsa Rosenthal's Artifacts in Alexandria. An antique table and cabinet, a flower upholstered chair and a rag rug are in keeping with the rest of the room.

A pleasant garden, Ryan's responsibility, stretches across the back. Lewis is threatening to build a glass extension to the kitchen across the back deck.

Upstairs, Lewis and Ryan have their collection of Victorian beds, including one pair of high-backed twins and another elaborate brass one. The big front room on the second floor is their painting and sculpture studio -- a pleasant and practical place.

Dupont Circle may well be one of the country's greatest places to live, thanks to the imaginative remodeling of the people who live there.