DEERFIELD, MASS. -- "In all traditions, the roof represents the essential element of shelter, and once the frame of a roof exists, the shape of a building comes clear," Pulitzer Prize winning author Tracy Kidder writes in House, his architectural exegesis set in central Massachusetts.

Not far from Kidder's own home near Amherst, a lead-coated copper roof recently poked its nose up between white pine and river birch, puncturing the placid skyline of "The Street," a strand of historic houses along Deerfield's main thoroughfare.

Taking shape beneath the roof's steeply gabled silhouette is what any Post Modernist would recognize as a barn. A faded shade of tomato red, it is a starkly rectangular structure pierced with a scattering of tiny apertures. In case the reference is in doubt, two weathered brown tobacco barns alongside echo its shape in sotto voce.

Still, as Historic Deerfield's public relations director Grace Friary drolly admits, a farmer stumbling upon this outsized shelter might be more than a little surprised. Completed in May, the 27,000-square-foot building is not really a barn but the museum's new Collections Study Center, Deerfield's first major construction project since the inn was renovated in 1980.

The center is the result of phase one of a two-part $12 million capital campaign launched in January 1994. The new facility cost $6 million to build; another $2 million was raised for its ongoing maintenance. On August 19, Historic Deerfield announced that it had completed phase one two weeks before the deadline for meeting a challenge from the Kresge Foundation for $500,000. Among 570 contributors are the National Endowment for the Humanities, the Arthur Vining Davis Foundations, and the Brown Foundation. Phase II of the capital campaign is also proceeding ahead of schedule. A million of the $4 million goal for general endowment has been met.

Set back from "The Street" by 350 feet, the Collections Study Center manages to be both monumental and unobtrusive, no small feat for a two-story, concrete-clad newcomer in an archaic world of clapboard siding and documentary paint samples. Designing it required meticulous attention to the museum's practical needs as well as the aesthetic and environmental requirements of the village, as Philadelphia architects Ueland Junker McCauley can attest.

For its distinctive coloring, lead architect Anthony Junker looked to the center's nearest neighbor. The circa 1725 Dwight House is painted cream with touches of dusty blue and red. Its mottled slate roof subtly sets the tone for the center's distressed facade, whose variegated texture was achieved through sandblasting.

One of the architect's few concessions to ornamental embellishment was the entrance, which incorporates cast panels with motifs derived from artifacts in Historic Deerfield's well-known collections, including a Wethersfield and Hadley chest, an embroidered rug, and a candlestick.

"We didn't want a signature building. We told the architect that at the outset," says Historic Deerfield's executive director, Donald R. Friary. "We didn't want the exterior to compete with the village environment, or the interior to compete with the collections." The interior's subdued palette combines three shades of gray paint, touches of cherrywood trim, gray carpeting and vinyl flooring in imitation of slate.

Completed in a year, the Collections Study Center houses gallery space for changing exhibitions, a permanent setting for the Helen Geier Flynt Textile Museum, and open study/storage facilities for roughly 9,000 artifacts. Curatorial staff gets new offices, conservation and photography studios, and an object preparation workspace. For the public there are meeting rooms and computerized access to objects on view in open storage.

"We didn't sacrifice anything in terms of quality or essential space, and we actually cut the cost of the building substantially in the last round," says Friary, who benefited from the experiences of Colonial Williamsburg and Winterthur, where similar projects have recently been completed.

"Walking in, people will see two cases with recent acquisitions," Friary explains during an early spring tour, shortly before curatorial staff moved into its new home. With admiration for its artfully exposed rafters and ductwork, the director looks up at the lobby's cathedral ceiling and beyond to the glass-sheathed expanse of visible storage, ultimately the repository of 3,500 objects.

From the lobby, visitors are invited to ascend the open stairway, bringing to mind Marcel Duchamp's famous depiction of modernism in motion. "They enter open storage through a glass box and are surrounded by objects," Friary says. "There will be cases for ceramics, glass and metalware. Furniture will be lined up against the glass."

At the base of the staircase is the entrance to two galleries, one for changing exhibits, the other for textiles. The latter has curved walls. "It is well-suited to costume and textiles because they are flexible," Friary explains. The textile gallery leads through pocket doors to the temporary exhibition gallery. The unadorned space, which features an entire wall without exit signs, thrilled the museum's exhibit designers. Across the way is a seminar room, which will have room for 40 people and several large casepieces. Upstairs, a classroom has been set aside for meetings of staff and Deerfield's annual summer fellows.

For the first time, staff photographer Amanda Merullo will no longer lug heavy equipment around Deerfield's none-too-compact campus. The photographer's studio - a hollow, high-ceiling space that could easily double as a kunsthalle for contemporary art - is adjacent to her office and many photo files. In her darkroom is a sink salvaged from the Deerfield Inn, which burnt in 1979 and was rebuilt at a cost of $2 million by the museum.

An objects conservation workshop on the ground floor will soon receive visiting conservators and Historic Deerfield's upholsterer, who works under the guidance of curators using the latest re-upholstery techniques. A textiles conservation laboratory includes both vacuum and water table for cleaning fabrics.

"The temporary storage facility is designed to accommodate the contents of one house museum," says Friary, recalling a time not long ago when curators fumbled in dark corners retrieving and replacing collection items. Temporary storage will also serve as a staging area for exhibitions, and as a checkpoint for processing new acquisitions and loans. Entering objects will be spared the shock of the new, lodging temporarily in a small antechamber whose micro-climate is minutely adjustable.

In May, curatorial staff moved out of several warren-like nests behind the house museums and in the administrative building into rationalized, state-of-the-art quarters affording some of western Massachusetts's finest views. A rear entrance leads upstairs to a chevron arrangement of offices, occupied at one end by architectural conservator Bill Flynt and by deputy director and curator Philip Zea on the other.

Down the hall from staff is secure/compact storage, housing 4,200 textiles, ceramics and furniture, including duplicates, teaching objects and light-sensitive wares. Collections manager Will Garrison worked with the designers on plans for the new facility, which boasts reinforced doors and floor, and rolling shelves for maximizing storage.

Sophisticated devices, including steam humidifiers for precisely maintaining the interior climate, are lodged in the attic. "It's very complicated as far as a smaller building goes," says site superintendent John Randall, pointing out a tub designed to catch spills and leaks before they happen.

When Historic Deerfield's Collections Study Center opens on September 25, 1998, the public will at last be able to explore the museum's extensive collections and learn more about the village's development through a thematic display organized by Zea and assistant curator Amanda Lange.

Focusing on the spread of gentility in rural, western New England and in Deerfield particularly, the 150-object show will be the largest organized by Zea since he arrived at Historic Deerfield in 1981. "Basically, it will look at how the `haves' discerned themselves from the `have nots,'" says Zea. "The acquisition of various social skills and emblems of a refined way of life were an expression of social power."

The curators' other big project is organizing and interpreting visible storage. "It is tough finding a balance between storage space and teaching space," says Zea, whose approach has been to "divide and conquer," placing small exhibits on technology between cases of otherwise uninterpreted material.

"We needed this building desperately," Don Friary says later over lunch � tuna sandwich, no chips, no sprouts. "It will make such a difference to the way we operate and realize our potential. We have outstanding collections. They should be shown, interpreted, and researched."

In his 32 years at Deerfield, Friary had never been so intimately involved in building. The process, from budgeting to blueprints to bulldozing, was both instructive and highly relevant to Deerfield's progressive sense of history. "What fascinated me was that the construction of this steel frame building was very much like the construction of a timber frame building in 1750. Everything is there."