Within a crowded urban landscape, open spaces stand out. Every city has them: oddly-shaped, forgotten parcels of land left behind in the rush of earlier development. Using an unwanted 1/3-acre gap adjoining a four-way intersection, Tucson architect Bob Taylor tucked a 1,600-square-foot main house around a landscaped courtyard and still found space for an office and guest quarters.
Reducing noise from traffic on the nearby streets and designing a residence that would afford him complete privacy were two of Bob's priorities. The others were building a home with an open and spacious floor plan, maximizing solar heat gain during winter months while minimizing it during the Tucson summers, and juggling spaces for two detached guesthouses and a possible third guesthouse.
One of the privacy-enhancing techniques Bob used is 10-foot-high perimeter walls made from sound-absorbing sand-filled concrete blocks. Tucson building codes allow 6-foot walls along property lines, but Bob realized that wouldn't achieve his privacy goals. Instead, he placed the 10-foot walls an allowable 25 feet back from the property line, filling in the space outside the perimeter walls with low-maintenance desert scrub plants such as mesquite and creosote bushes. Only the main entry doorway and garage door break the stucco surface of the walls.
Some walls of the home facing the street were formed using Polysteel molded foam blocks that can be stacked to create walls. Once the blocks are assembled, concrete is poured into a center cavity to create a sandwich of concrete between insulating layers of foam. The exterior is then given a protective finish coating.
"Polysteel gave me two big advantages in terms of its insulating and sound-deadening qualities," Bob says. "I probably paid more to have [the Polysteel] put in at the building site, but I've recovered that investment and have saved money in my long-term cooking and heating costs."
Borrowing from the Mexican concept of building residences around courtyards, Bob oriented his home so its south wall faces a courtyard with a fountain, pool, fireplace, and tropical plants such as Key limes, thin-leaf figs, and hibiscus. Glass panels for windows and doors dominate this wall and flank a living room fireplace. During winter months, the sun's low angle allows direct light into the living room where it heats the poured concrete floor. A roof overhang shields this room from direct sunlight during Tucson's intensely hot summers.
Lighting is done naturally, too. Skylights stretching the length of the house achieved Bob's goal of directing natural light into the home's core. These windows direct sunlight onto a series of concrete walls that collect solar heat and release it slowly at night to warm the interior. Ranging from 42 to 84 inches high, these walls also define the various living areas with no loss of openness.
Changing floor levels also define the interior spaces. The living and dining areas are on one level, while the adjoining kitchen and family room are elevated two steps. The master bedroom is six steps up a wood stairway, a design twist that enhances privacy and creates a basement beneath the master bedroom suite.
A secluded balcony adjoining the master bedroom is connected by five stairsteps to a 12 x 16-foot swimming pool. Adjoining the 4-1/2-foot-deep pool, behind a landscaped divider, is a somewhat more shallow 4 x 12-foot fish pond with foundation. Bob uses his pool for taking cool dips on summer days and relaxing poolside with the morning newspaper. He grows watercress in the fish pond. The pool waterfall and pond fountain create a constant sound of running water, which masks noise from the nearby city streets.
To create a home office and provide for guest quarters, Bob designed two separate guesthouses, each with a private bathroom, along the perimeter wall opposite the main residence's south-facing wall. One is for his busy architectural practice, which covers commercial and residential projects across Arizona. Should one of his elderly parents move to Tucson, Bob left room to construct a third guesthouse.
By incorporating a few simple techniques, homes anywhere can benefit from solar gain.
- "Figure out how you want to 'mass' your house if you're building features that retain solar heat -- things like concrete walls, large windows, courtyards, and tiled floors," Bob says. "The simplest feature to start with is designing one of the home's walls to face south, and then building lots of glass into this wall."
- Although south-facing windows allow direct sunlight into a home during winter, during summer those same windows will overheat interiors unless the wall also incorporates a sun-shielding roof overhang.
- Bob advises using solar charts, which are readily available at any public library, to research the angles at which the sun's slant will travel across your homesite during the year. As the sun progresses south throughout the year, pick the point at which you want to cut off the sun's direct path into the house. Design your roof overhangs to block the sun after that date, which will vary by climate.
- In Tucson, where the desert climate sends daytime temperatures toward 90 degrees by mid-March, Bob used the first day of spring as his sunshine cutoff date. Homeowners in Northern climates will want to delay that cutoff date until their local climate becomes uncomfortably warm.
- For desert climates, Bob advises insulating a structure's east and west walls to fight summer heat gains. He also suggests limiting the number of windows in these surfaces. "The better your insulation qualities, the more heat you'll block in summer and retain in winter," he says.