In the drive to increase density in cities to accommodate the increased demand for housing among younger urban professionals, planners and developers have concentrated on taller multifamily buildings full of apartments and condominiums.

The Great Recession halted the building boom, leaving many developers and architects averse to large-scale projects with greater financial risk and exposure to long-term construction liability. In response to these factors, as well as changing market preferences, some developers are now experimenting with small- and intermediate-scale projects to increase density in a shorter time frame and at lower risk.

At the same time, most architecture firms no longer design single-family houses except for very wealthy clients. Some firms are experimenting with designing single-family homes at intermediate densities that enable them to spread their fees over more projects than when they work on one-off, high-design, custom-built houses.

Some cities recognize that increasing density in urban areas outside commercial cores requires experimenting with ordinances that increase flexibility for developers to infill smaller sites in a way that permits more innovative solutions to site planning problems.

Los Angeles enacted a small-lot ordinance to allow construction of fee-simple, infill housing on small lots in multifamily and commercial zones as a way to enable compact building footprints and minimal streetfront and setback requirements. Whereas homeownership options traditionally had been limited to condos or single-family homes on typical 5,000-square-foot (465 sq m) lots, the passage of the small-lot ordinance extends ownership options to include townhouses, rowhouses, and other types of infill housing typically only available for rent.

Elan Mordoch, a Los Angeles developer of high-design apartments and condominiums through his company EMC Partners, perceived the opportunity the ordinance presents to create profitable single-family housing designed by well-known architects at an intermediate scale. Such units would now be feasible because the design fees and land costs could be spread over more units while both higher-quality design and outright land ownership would allow creation of units that would be in higher demand and of greater value.

Mordoch found a large older, single-family house with six bedrooms but only two bathrooms, located on a lot 80 feet (24 m) wide—60 percent wider than the standard 50-foot-wide (15 m) lots in the neighborhood—and 140 feet (43 m) deep. The Los Feliz area, just east of the higher-end Hollywood Hills, is becoming a higher-density neighborhood and draws people attracted to its revitalized shops and restaurants, as well as to recreational and educational offerings in nearby Griffith Park, where a large observatory is located. Two-story apartments border the site on three sides on Kenmore Avenue, a tree-lined two-lane street with two parking lanes and sidewalks. A six-story apartment building stands across the street.

Under the zoning of one unit per 1,500 square feet (139 sq m), the quarter-acre (0.1 ha) site could hold as many as seven apartment units. But using the small-lot ordinance, Mordoch and Los Angeles–based Rios Clementi Hale Studios (RCH) found a way to design and build six 1,800-square-foot (167 sq m) urban houses on three levels, each with three bedrooms, three-and-a-half baths, a two-car garage, and a roof terrace. This works out to 24 urban houses per acre, almost four times as dense as the predominant single-family-lot pattern of 50-by-140-foot (15 by 43 m) lots.

The challenge was to plan the site and each of the houses in a way that would make the whole site, and each of the houses, urbane as well as dense. And that required very careful design so that each house is light and airy and exposed on three sides to the outdoors, yet private. There were to be no constricted inside units.

The site-planning technique chosen by RCH architect Michael Martinez and principal Bob Hale was to create an articulated courtyard in the center of the site surrounded in a U shape by three sets of two houses each.

Unlike the more typical townhouse configuration, which would share long walls with only limited light and air admitted at either end, Martinez butted only the short walls of the two-house groupings, exposing the two long walls, as well as the opposite short walls, to light and air. Rather than a common party wall, those paired short walls are actually separate structural walls with one foot (0.3 m) of space between them covered by a sheet-metal expansion joint.

What appears to be the common courtyard actually is owned as adjoining lots of each of the six houses. The driveway provides shared access to all the owners, and a maintenance agreement covers its upkeep. Although the courtyard is only 26 feet (8 m) wide, it is articulated with pervious pavement and planting beds and acts as a driveway providing access to the houses. The T-shaped driveway provides space for cars stored at each house at the end of the courtyard to back up before driving away.

The lots are different sizes, offering somewhat varied private outdoor space. The lots for the two front houses are 1,800 square feet (167 sq m); the two more secluded lots at the rear are 1,600 square feet (149 sq m); and the houses in between have the largest lots at 2,000 square feet (186 sq m). In addition to separate designs for the private outdoor space at grade, each unit has an accessible roof terrace of about 400 square feet (37 sq m).

The site plan for the houses uses the same basic 22-by-35-foot (7 by 11 m) footprint for each building. However, the orientation of the houses on the lots and the floor plans within each house provide variation that allows each to take maximal advantage of exposure to the sun, privacy, and views. The shared driveway, designed as a courtyard, also permits much more control over views.

A common problem when identically designed units are juxtaposed across small courtyards is that the windows of one unit look directly into those of its opposite neighbor. One benefit of having an architectural firm experienced in custom house design is its ability to avoid such conflicts. Rios Clementi Hale used high clerestory windows to maintain privacy yet admit light and air. In other locations, double-height windows were juxtaposed with solid walls containing stair towers, for example, between the rear units and those in the center.

The footprint of each house provides about 770 square feet (72 sq m) of space per level to incorporate a variety of functions and spaces. At grade, a garage can house two cars, one compact, in 16- and 22-foot-deep (5 and 7 m) spaces. A flexible 430-square-foot (40 sq m) space with a full bathroom carved out of the garage area can be used as a home office or a guest bedroom. If a kitchenette were added to the space, it might be turned into an accessory dwelling unit.

The second level of each house contains the living and dining rooms, the kitchen, and a half bath in a variety of configurations depending on where the internal staircase is placed. Bay windows with floor-to-ceiling glass, kitchen islands, and gas fireplaces articulate the living spaces. Because the houses are 36 feet (11 m) tall, including the roof terraces, internal spaces on the second and third floors are nearly ten feet and nine feet (3 and 2.7 m) tall, respectively, filling the rooms with light and expanding their more-compact areas.

The third level contains a master suite with a separate shower and tub, dual sinks, and a walk-in closet; a second bedroom; and a laundry closet.

The choice of fee-simple lots rather than what could have been apartments or condos changes a broad spectrum of development considerations. The market for fee-simple ownership is broader, and the home values are higher than those for communal ownership. In Los Angeles, condo association fees are more than $400 per month versus no more than about $60 to $80 for the shared-maintenance expense at this development, Mordoch says. At that rate, he contends, the expense differential alone amounts to about $70,000 in capitalized value. In addition, other potential capital assessments for condos, and their shared-decision-making structure, do not appeal to many prospective buyers.

From the developer’s perspective, the approval process for condos is very different from using the small-lot ordinance to secure a specific set of entitlements. “For example, the small-lot ordinance allows for certain setback reductions for side and rear yards,” says Mordoch. “However, these setback reductions are discretionary, and the entitlement outcome is less clear from the outset than for most condominium entitlements, where the building envelope is a function of the lot’s specific underlying zoning parameters.”

For both architects and developers, construction liability insurance for condos, as well as the time and expense of litigation required for many projects, often makes the risk and cost unacceptably high. Says Martinez, “The architectural insurance requirements for condominium projects make them less attractive than the fee-simple housing allowed by the small-lot ordinance.” Also, unlike the condominium statute administered by the state, the small-lot ordinance is administered locally.

The higher market value for fee-simple ownership was important in order to make the project feasible. Mordoch bought the single-family house and lot in April 2013 for $730,000. He expects each of the six houses to sell for about $850,000, which he says is competitive in the Los Angeles market. He notes that high soft costs for the project add at least $70,000 per unit to the land costs.

Mordoch worked closely with architects to simplify the structural diagram, making the units more efficient and more straightforward and less expensive to build. He notes that the simple rectangular, common footprints and diagrams of the units eliminate additional footings, as well as internal shear walls, reducing cost without lowering quality. And external shear walls are stacked, eliminating the need for expensive transfer beams. Such techniques allowed him to select more-expensive commercial-grade architectural window systems, stucco and wood siding, quieter cast-iron plumbing rather than plastic pipes, and other materials and finishes while maintaining feasible margins.

He says he and his equity investors are confident that the extra costs for nearly custom design will appeal to a discerning market of 25- to 50-year-old urban professionals, many with smaller families, who seek a more urbane lifestyle in a walkable neighborhood close to cafés, restaurants, and a mixture of other services. Completion is scheduled for April 2015.

This kind of innovation in intermediate-scale single-family housing development offers an alternative to more complex urban solutions. The city was able to increase the density of single-family housing to 24 units per acre (60 units per ha), a density common in garden apartments. The developer was able to create higher values with complete fee-simple ownership, and at lower risk. The architecture firm was able to make inroads in the design of single-family housing from which it had long been excluded except for high-priced, custom-designed, one-off houses. And a new kind of urbane single-family house, on lots owned outright, is available to those buyers often relegated to more distant suburban locations.

William P. Macht is a professor of urban planning and development at the Center for Real Estate at Portland State University in Oregon and a development consultant.