The dramatic rooflines of the cedar-clad contemporary house rise to thhthe treetops of its wooded Annapolis lot, and the house itself hoovers on a bank of the Severn River. Even on a gray fall day, the house is bursting with light and a sense of spaciousness. The culmination of years of trial and effort, the "SS2200" is not just another modern housw; it is one of the latest in kit houses.

The house, designed by Acorn Structures Inc., was built by a local builder from Acorn's pre-cut and partly aassembled parts. It comes complete with solar collectors and detailed plans for passive heat storage and an elaborate computerized monitor for the solar collector and storage tank.

Not all kit houses are as dramatic, or as energy-conserving as thhe house pictured on these pages. But increasingly kit houses are more flexible than tract houses, offering extensive custom features without architect fees, a multiude of plans to choose from for just the right house on a specific lot, and a continouous refinement in design tthat often means any mistake in a design will not be repeated.

The modern kit house does not come neatly packaged in a box with everything needed. Most provide all the basic structural elements, exterior finishes (siding, roofing, windows) ans some inside materials such as moldings, doors and cabinets. A kit house buyer still has to find suitable land and a good builder to put up ttheehouse. In some cases architectural engineering in adapting the house to the site is offered by the manufacturer; in other cases an outside consultant must be hired.

There has always been a good market for kit houses in resort communities. Small, efficiently designed houses can be shipped to almost any site, saving the prospective second-home owner the trouble of finding a local architect and beginning from scratch on the design.

The market for kit houses has expanded to the primary home as well, and with it the designs have multiplied. Today's kit house might be one next door or down tthe street. About 200 Acorn designs have been built in tthe Washington area alone, for example, and many people are unaware that some modern houses they see emerged from a kit.

The combination of fast track building techniques, new advances in energy-conserving designs and the efficient and dramatic uses of space make the kit house one to watch for hints of things to come in housing of all types.

"For a long time, people looked at kit houses because they were more economical than building a custom-designed home," says architect Don Hawkins, who cut his architectural teeth on adapting kit houses to sites all over tthe Washington area for Techbuilt and other companies.

"What a kit house does is get you halfway through the process of having an architect-designed home without paying for it," says Hawkins. "In fact, today's kit houses aren't really that different in cost," says the architect. "It's a difference that translates in terms of the quality of some of the materials."

Of the dozens of companies all over the country, some provide pre-cut parts, others "panelize" or provide pre-cut, pre-nailed windows already set into the walls in widths as wide as 12 feet. This makes putting up a house quick work and cuts on-site labor charges. There are firms in tis area that specialize in panelizing homes for individuals, architects and builders.

The kit house has come a long way from the classis second-home A-frame. There are godisic domes, octagons, ramblers, split-level homes, traditional designs, log houses by the dozens and a selection of classic contemporaries.

Unlike cookie-cutter homes in a tract development, there may be thousands of models of the same kit house, but the are located individually in neighborhoods all over the country. And each time thy are built, the owner and the kit house company negotiate for changes, customizing the design. Such feedback makes it possible for kit house manufacturers to change their offerings when they see an idea that improves their origianl concept.

At its best, a kit house can provide the buyer with a tested design, refined over time. At its worst, a kit house can be poorly adapted to a specific site, poorly designed for a family's needs or poorly constructed.

There is a classic look to the contemporary kit house: dramatic ceilings, clerestory windows, steeply pitched roof lines with big overhangs and lots of visible timbers or wooden beams. The actual square footage may be no bigger than in a traditional house of three bedrooms, but the sense of space is dramatically different.

The contemporary developments of Hollin Hills in Alexandria and Carderock Springs, Ms., evoke the feeling of many kit houses. Like kit houses, they boast cathedral ceilings, lots of windows, sliding glass doors to decks and balconies and an emphasis on antural materials -- woodenclad ceilings, visible beams and a strong relationship to the site.

It is the shape of the interior spaces that makes some of the better kit house designs so noteworthy. To enhance their offerings, Acorn, one of the biggest and oldest builders of imaginatively designed kit houses, linked with the Raytheon Corporation in 1973 and came up with a design for a solar house, a combination of active and passive solar designs. The house that has emerged since 1973 combines the imaginative uses of spce that characterize many Acorn Designs with the best technological and design advances that they could build into a kit house.

Like the quality car or plane kit one purchases in a toy store, a good kit house will cost as much if not more than a finished ready-made home. Construction costs run at least as much as tthe cost of the kit, plus the cost of land and site preparation.

The Solar house pictured here is a slightly expanded version of the standard SS2200; its price tag: $86,000 for the kit alone. The finished house cost about $200,000, exclusive of the waterfront site. Cheap it isn't; pretty it is. This winter will ttell if the design meets its energy-conserving expectations.

At the other end of the financial sspectrum is an equally imaginative design by Acorn called the Loft 800 -- a box, 24 by 24 feet. The 800-square-foot design is a clever use of loft space for a bath and bedroom, with the kitchen area below. Its price tag, for the kit alone, is $24,300. The cost of construction would probably run about another $24,000 to build, not including the cost of the land.

If one is amitious, one can always buy the kit and build the house without benefit of a contractor. That's exactly what Matt and Solveigh McCulloch did over 10 years ago. They spent $14,000 for a modified A-frame for their Bryce Mountain getaway. Unfortunately for the McCullochs, who like to do things themselves, their adventure in kit-building started on the down side -- literally. The truck carrying the windows, roof trusses, siding, all the studs and joists, slipped on a steep incline -- and before anyone know what was happening, all thhe goodies tumbled into a ravine.

"We spent a week carrying the lumber up to the site -- and of course, it was raining every day. It was horrible," recalls Solveig McCullouch. The couple is till putting the finishing touches on their house more than a decade later.

Fortunately, not everyone takes on the challenge of doing it themselves, which while cutting the dollar costs can take its toll. The McCulloch house was designed and put up exactly according to the standard kit offered by the now defunct New York State firm manufacturing Aframes. While building it without a contractor suits only a handful of potential buyers, many like to take a liberal hand in the design of their almost-custom home.

Big operations like Deck House and Techbuilt and Acorn, all of which operate in the greater Washington area, allow their clients freely to adapt their houses for little or no design fee., Several years back, Fred and Sharon Spilhaus brought land in Potomac and went to Techbuilt with some ideas. Spilhaus looked at the designs the firm offered and then took a scissors and tape and began to combine elements of several standard offerings. All tthis thinking was then taken ot architect Don Hawkins who translated those ideas into a Techbuilt kit house complete with a delightful two-story library off the master bedroom suite. What Spilhaus and Hawkins did was to take that dramatic expanse of space provided by the cathedral ceiling on the first floor and build a catwalk off the master bedroom accessible by a doorway from above and a ship's ladder from below. The effect is a dramatic, efficient use of what otherwise would have been soaring but effectively useless wall space.

The knack of a kit house seems to be in taking ordinarily small spaces and making them seem alrge by the use of soaring ceilings and clever uses of what architects call site lines -- openings in walls to allow you to see through to the next space and beyond. None of the rooms are any bigger than in most tract homes, but the sense of space is far more expansive, and that, it seems, is the name of the game for today's housing. Where to get kits that explain the kits

For more information on kit houses, contact Home Manufacturers Coucil, 1201 15th St. NW 822-0576. Information also is available in The Kit House Catalog by Michael Coffee (New York: Pocket Books, 1979).

Manufacturers mentioned in this article:

Acorn Structures, Inc., 1809 Mill Ridge Court, Annapolis, Md. 261-1781 or 301/757-5220.

Techbuilt New England, 6801 Whittier Ave., McLean, Va. 734-0557.

Deck House, 2003 Huntwood Dr., Gambrills, Md. 858-0626 or 301/793-3949.

Three local firms will panelize house pland to make a kit or offer kit designs themselves:

Cumberland Corp., 10706 Vandor Lane, Manassas, Va. 631-2048 or 471-6111. Offers about 40 models of vacation and primary homes, including a solar model.

Northern Counties Lumber, P.O. Box 97, Upperville, Va. 471-4035. Will panelize any house plan; also offers 25 vacation and primary home kits and soom will offer an all-wood, earth-sheltered kit house.

First Colony Homes, P.O. Box 224, Calverton, Va. Metro area: 2738817; Virginia: 703/788-4222; Prince William County: 703/369-7799. Will panelize any conventionally framed house plans. CAPTION: Pictures 1, typical of innovative and dramatic kit house design for the 1980s is Acorn's Solar Series 2200 (about 2,200 sqaure feet), this one built in Annapolis for $190,000 plus the cost of the lot. Margaret Thomas; Picture 2, the view from the kitchen. The quarry tile floor is not just decorative. It rests on a foot-thick mass of crushed rock that helps store heat for the south facing house. Margaret Thomas; Picture 3, the living area of the house boasts wall cut throughts with views into other rooms. Margaret Thomas; Picture 4, this exterior view of an Acorn "Crow's Nest" house in Cabin John shows the fornt entryway. The living room, with its four clerestory windows, is the section of the house to the left, the bedroom wing, the section to the right. Not visible from the angle is the "crow's nest" itself, a tiny 5-by-5 office tucked away at the very top of the stairs. Margaret Thomas; Picture 5, Nearly every room in this Acorn "Crow's Nest," which is in Cabin John, opens on to the central staircase. This feature and the cathedral ceiling in the living room give an air of great openness to a house that has relatively little floor spare. All of the bedrooms alsso have cathedral ceilings, making them seem less cramped as well. The exposed beams are characteristic not only of Acorn structures but also many other contempory kit houses. Margaret Thomas; Picture 6, The library of Fred and Sharon Spilhaus' Techbuilt house in Potomac has a catwalk accessible by doorway from the master bedroom or by ladder fromt he floor below. Margaret Thomas;