It could be argued that our current national housing policy -- at least pertaining to low- and moderate-income families -- is to have no national housing policy.

Although federal involvement in financing and producing affordable housing has steadily dwindled, efforts by state and local governments have continued. Likewise, some developers, architects, engineers, landscape architects, contractors and building material manufacturers continue searching for ways to create housing for less cost.

It's a tough search, for reducing significantly the price of housing is increasingly difficult.

On the one hand, consumer expectations are higher than ever, regardless of income level. People today take for granted spacious rooms, air conditioning, dishwashers, refrigerators with icemakers, prewired cable TV, sound-proof walls and maintenance-free exteriors.

Such aspirations are reinforced constantly by media messages. Surely the biggest kitchens, living rooms and bedrooms to be seen in America are those depicted routinely on television sitcom and soap opera sets.

On the other hand, the price of labor and materials -- so-called hard costs of a dwelling comprising site preparation, utilities, landscaping, structure, enclosing skin, plumbing, electrical and mechanical systems and finishes -- has risen faster than average American incomes.

And all housing, whatever its type, must still satisfy local, state and national building codes that generally establish minimum design standards for comfort and safety. Below such minimum criteria, further cutting of quality or quantity -- and costs -- is presumably unacceptable, if not illegal.

In addition to codes, zoning ordinances generally limit housing densities on residentially zoned land. Affordable housing, no matter how cheap the housing unit itself, may be precluded in many locations simply because of the cost of land and the quantity of grading, excavation, piping, paving and landscaping required for land development.

Therefore, to lower housing costs, design and production tactics must whittle many different elements of expense, rather than hacking away at only a few.

Reducing land and land-development costs remains a high priority, and one tactic for achieving this is to allow increases in residential density on sites designated for development of affordable housing. This necessitates public intervention, but not necessarily public expenditure, to identify properties and devise zoning overlays. It also requires safeguards to ensure that affordable housing is a result, and that such housing is available only to low- and moderate-income households.

Substantial density increases, perhaps by several hundred percent, often are required to lower per-unit land costs to levels of affordability. To cluster units on sites and cut infrastructure costs, conventional yard and setback regulations also may have to be relaxed.

In the early 1970s I was able to design and build six new, detached, one-family dwellings on a single lot in the District of Columbia. The 39,000-square-foot lot, which already had a 1930s vintage house on it, couldn't be subdivided into separate lots because of an inadequate frontage.

But the D.C. zoning ordinance, which prescribes minimum lot sizes of 5,000 square feet in R-1V zones, such as this lot, allowed up to seven houses on the property without subdivision if the dwellings collectively had adequate "hypothetical" yards surrounding them. Moreover, the houses had to share a single driveway, water supply and storm and sanitary sewer connections.

An unorthodox site plan, made possible by liberal but enlightened zoning interpretation, dramatically lowered the land cost per dwelling unit. The lot and original house sold for $57,000 in 1971, of which about $33,000 represented the value of the bungalow and its one-seventh share of land. Consequently the effective land cost for the six new houses was only $24,000 or $4,000 per dwelling, a bargain even in 1971.

In designing affordable housing units, architects and developers must make tradeoffs among several variables, all of which directly affect cost: size of unit, both in floor area and volume; dwelling shape and geometric complexity; type of structure and type and quality of "skin" (including roofing, siding, insulation and windows), heating and air conditioning systems, equipment and finishes.

They must evaluate first costs against operating or life-cycle costs, knowing that generally better products, while more expensive, last longer and require less repair and maintenance. But some products or features can be omitted, while cheaper ones installed initially can be upgraded later. Moreover, houses can be designed so they can be expanded.

This implies investing generously in those components of a house that are most permanent, most difficult to modify and most critical for durability and satisfaction of basic shelter needs -- the building shell.

Thus, savings can be achieved by forgoing garages and carports, fireplaces, trash compactors, electronic air cleaners, intercoms and built-in furniture. Even closet doors are optional, although adequate storage is not. Inexpensive materials can be used for items not affecting structural integrity or weatherproofing. Such components include kitchen appliances and cabinetry, decorative trim and millwork, light fixtures, plumbing fixtures, interior painting and finished flooring. All of which can be upgraded later when household economic conditions improve.

By contrast, the basic shell of the housing unit -- structural frame, roofing and flashing, insulation, sheathing, siding, windows and glazing, exterior doors, sealants -- should not be compromised. They must be durable, weatherproofed and energy conserving.

Another tactic is to make spaces that are enclosed but unfinished. Potentially habitable attics and basements are especially cost effective since most of the components needed to enclose them -- roofs, structural framing, foundation -- have to be constructed anyway. If configured properly for future modification, such cheaply built spaces can greatly expand personal living territory with modest expenditures.

Architects also can design housing to accept additions more readily. Proper siting of dwellings can reserve yard space in which to expand. Internal room and circulation patterns can be extendable, either vertically or horizontally. Windows providing critical light and ventilation can be placed to avoid conflict with later additions. Foundations and structural elements can be sized for increased loads imposed by vertical expansion. And overall house geometry can permit visually harmonious massing when new wings, bumps or bays are appended.

Affordable housing is still possible, but only through a combination of efforts. Designers and builders must continue looking for incremental, cost-saving gestures when they may shape housing units. Municipal and state governments must continue considering and adopting new policies that decrease land and financing costs. And consumers must postpone fulfillment of wish lists.

Unfortunately, regardless of how costs are trimmed and expectations lowered, many American families still will need subsidies to rent or purchase any kind of decent housing. Roger K. Lewis is a practicing architect and a professor of architecture at the University of Maryland.