Among life's certainties -- death, taxes, hitting every pothole, always being in the wrong supermarket checkout line -- is the agony of remodeling.

Face it. Pain and suffering are part of the price for making anything other than cosmetic changes to a house or apartment.

Remodeling means enduring demolition and drywall dust; unraveling the mystery of how concealed structural, mechanical, electrical and plumbing systems are built and where they are located; and coping with countless unforeseen defects and deterioration, ranging from rotting or insect-infested wood framing to sheathing covered with mold.

Still, we feel compelled periodically to modify the size, configuration and aesthetic character of our personal living environments. This compulsion is fueled by strong desires for updated dwellings that accommodate changing household needs and activities, incorporate new technologies or respond to shifting tastes.

We endure losing the use of kitchens, bathrooms and bedrooms, sustained by prospects of a more fashionable kitchen, a swankier bathroom, a more commodious master bedroom with spacious walk-in closets, or a new study or studio.

All this points to another fact of life: Residential needs at ages 30, 50 and 70 differ significantly, as do household composition and finances. For a given amount of living space, a layout suiting a family of four is unlikely to be what a first-time homeowner needs. And when the family of four eventually becomes a pair of empty nesters, yet another layout is needed.

These realities are among the reasons that the Partnership for Advancing Technology in Housing (PATH) recently created the PATH Concept Home. A cut-away, scale model of the home, designed by Torti Gallas and Partners-CHK Inc., was unveiled last month at Union Station's Columbus Club.

PATH, which is administered by the Department of Housing and Urban Development, seeks to demonstrate that American homes can be designed and constructed to be much more flexible and adaptable to evolving needs.

"Open building" is PATH's primary strategy for achieving flexibility. Open building entails separating a dwelling's utilities -- networks of electrical wires and telecommunications cables, supply and return air ducts, and gas, water and waste pipes -- from structural and enclosure systems, in which utility networks typically are interwoven and buried.

Disentangling utilities from structural and enclosure components liberates the floor plan. Free of wires, pipes and columns, interior partitions can be easily eliminated, modified or added, allowing existing rooms to be expanded, shrunk, merged or reshaped. Such a system eases replacing or relocating plumbing and electrical fixtures, rewiring, and even relocating ducts and pipes.

To make visually dramatic two-story spaces or accommodate new stairways in multi-story dwellings, holes can be cut into existing floors more conveniently if utilities are not threaded throughout the floor joists.

A new idea for homes, open building has long been the norm for commercial and industrial architecture. In office buildings, utilities are always separated from structural framing and enclosure systems -- exterior curtain walls, interior partitions, suspended ceilings -- to maximize flexibility as tenants and uses change over time.

The PATH Concept Home achieves flexibility and plan liberation first by using longer structural spans to form the building shell and eliminating interior, load-bearing partitions. Second, rather than being embedded within walls, utilities are placed in dedicated, accessible chases and raceways running under floors and in baseboards that serve as conduits. Changing layouts within the shell is greatly simplified, making remodeling cheaper, quicker and cleaner.

Design of the PATH Concept Home is also based on a three-dimensional planning grid, part of PATH's effort to encourage adoption of industry-wide dimensional standards for manufacturing and assembling building components. The aim is to adopt modular sizes and interfaces for fundamental construction elements -- structural members, exterior wall and roofing materials, doors and windows, partitions, interior finishes and trim, cabinetry, and utilities -- to streamline construction and reduce costs without sacrificing customization options.

If manufacturers subscribed to a universal system of modular measurement, designers and builders could freely mix and match construction products in a kind of "plug and play" process. They would know that, even though they come from different sources, components would be dimensionally compatible and would reliably fit together.

PATH further believes that if homes were constructed mostly in factories instead of in the field, the quality of production housing would increase while prices would decrease.

Ultimately PATH's mission is to radically transform the way American homes are built and remodeled.

The group's concept home, asserts last month's PATH media advisory, "will offer a new, dynamic vision of home building: By 2010, home design and construction will be efficient, predictable and controllable with a median cycle time of 20 working days from groundbreaking to occupancy. Efficient production methods will result in cost savings that make homeownership available to 90 percent of the population."

This is an ambitious, laudable but optimistic agenda. There have been many attempts to rationalize, modernize and dramatically economize home building. Yet no effort has succeeded at the scale envisioned by PATH, mostly because serious systemic obstacles persist: home building industry diversity, fragmentation and competition; diversity in design norms and building codes from place to place; regional and socioeconomic market diversity; and variable economic conditions affecting housing finance and production.

Nevertheless, the opportunity to profoundly transform the industry could be at hand. Affordable, flexible housing is increasingly in short supply. New technologies for design and construction promise savings in time and expense.

With housing prices always rising, Americans may be ready to buy a new home that is not only within financial reach, but also can be easily modified to fit changing needs.

If this happens, the agony of remodeling perhaps could disappear from the list of life's certainties.

Roger K. Lewis is a practicing architect and a professor of architecture at the University of Maryland.