BY DESIGN : CURRENTS : Chairs and tables are doing double duty as more dining rooms are becoming offices. And designers are happy to help.

More than 30 million Americans will punch the clock from home at least once this week.

That number has been growing 7% a year for the last three years, but only recently have companies delivered pieces that satisfy the discriminating home-office worker. The huge furniture makers say the special needs of these employees have made it a difficult birth.

Last month, Herman Miller for the Home opened a retail store on Beverly Boulevard in Los Angeles. The company, known for its sleek Eames and Noguchi furniture lines, is now carrying the new TD collection of home-office pieces that includes tables, desks, L-shaped returns, bookcases and storage units.

Steelcase, a powerhouse in the wholesale office furniture business, recently introduced a home-office line called Turnstone. And several smaller companies are turning their attention from the offices of the boardroom to the bedroom.

A few years ago, home-office workers had to make do with metal filing cabinets and stacks of bright plastic bins stacked on the kitchen table. And those who tried to make modular pod furnishings fit in with their French Provincial motif had a nightmare in their living room.

“Some people tried to take a desk from work and fit it in their homes and it stuck out like a sore thumb,” says Ken Tameling, spokesman for the Turnstone line.

The scale was wrong, the finishes too industrial, the storage space inadequate.

“Home-office furniture has to be smaller and lighter, and it has to blend in,” Tameling says.

Because few people have an extra room they can transform into an office, the furniture makers had to come up with designs that do double duty, going from nose-to-the-grindstone workstation to decorative showpiece.

Frezza, an Italian manufacturer with a slick line of home-office furnishings called Cassamania, offers odd-shaped tables that cluster into a large dining table by night and break apart into three desks by day--for less than $500. The company’s all-purpose shelf system might hold the computer as well as the family library and collectibles. A single wall unit is less than $500; a double, less than $750. Cassamania is available through Menzie International in L.A.’s Pacific Design Center.

Dimension Storage Systems does a like-minded bookcase/wall unit that has either a flip-down desktop (about $2,499) or a fold-down conference-size table (about $3,499). The murphy bed-like desks are made to order and come in a variety of finishes. The units are custom-made by California Closet Co., which has five area locations.

For those with more traditional taste, Kimball Furniture has created a line called Harmony Woods that includes wall units equipped to house computer monitors, printers, file drawers and keyboards. A double-pedestal desk with eight drawers--in cherry ($2,500) or oak ($2,375)--also has a pull-out shelf for a keyboard; both styles can be ordered from Eddie Gold Furniture in Los Angeles or Frank’s Furniture in Lawndale.

Above all, the home-office worker wants a compact, inconspicuous workstation, furniture designers say.

“Disguising the home-office environment is as much of a consideration as the design of the product itself,” says Ray Kennedy of Herman Miller.

Even those who leave their workplace desks looking like a landfill, for example, tend to keep things neater at home. “They want papers off their work tops so they can close up shop. This demands different kinds of storage,” Tameling says.

Besides offering compact storage systems, the new lines pay more attention to wire management (an industry term for containing the mess of computer/telephone/printer/fax cables that hang like errant pasta behind desks). Now, these tangles can be channeled into orderly, invisible submission.

As the selection of home-office furnishings has broadened, so has the price range.

Rubbermaid, the maker of snap-top leftover containers, has developed through its MicroComputer Accessories subsidiary a home-office desk of blow-molded plastic priced at $229. The SnapEase computer desk comes unassembled but, says a company representative, “It’s easier to put together than most toys.” It can be paired with hutch, $89.95, and printer cart, $59.95. All three are available at Dozar Office Furnishings in Culver City.

The Turnstone line includes a $99 open storage cabinet and a $259 contemporary-style, computer-friendly desk in mahogany or cherry finish. Steelcase outlets and some Office Depot stores carry Turnstone, or items can be ordered via catalogue, (800) 887-6786. On the high end, the Herman Miller designs top out at $8,000.

Another high-priced piece of home-office equipment is the ergonomically correct, posture-perfect, sit-up-straight, use-the-armrests and don’t-let-your-wrists-slouch-when-you-type chair. They have yet to be domesticated.

But Sheila Weiss, manager of Dozar Office Furnishings, says some local companies are working on home versions. “Chairplace is making ergonomic chairs with upholstered backs instead of the plastic shell backs. And some other companies are trying wood caps on the base so you don’t see the gray or black plastic pedestal.”

The price of an ergonomically correct chair can be quite an eye-opener. “A decent chair will cost $150. A really good executive style is priced closer to $400,” Weiss says.