The necessity of adjustments

The alley offset, described in the last Technical Page, is a way of modifying alignment of alleys from one block to the next. It is used where baroque excess in vehicle size and speed would otherwise result in corrosion of the alley system’s multiuse flexibility. A similar effect may be gained by varying adjacent block alley types — changing from a C pattern, to an H pattern, a T pattern and so on. While even more effective in slowing vehicles, this tactic has disadvantages for the continuity of underground utilities. But to think of alley patterns as susceptible only to such remedial adjustments is to miss a larger truth. Alleys are one of the great, complex, support technologies of civilized life. Beginning as mere backyard drainage ditches, they have evolved as the increase of societal wealth produced more intensity and variety of vehicular uses, delivery and haulage services, and utilities. The rise of alley use and the refinement of alley design parameters paralleled an increasing sophistication in segregation of noxious uses in increasingly dense towns and cities. It must also be noted, as regrettable historical fact, that certain human beings were considered less desirable members of society and therefore “logically” were quartered amongst the noxious uses on the alley. Post World War II modernist planning almost never had alleys, for two reasons. First, with the stunning clarity of planning methods that distanced large use categories (noxious or not) from one another wholesale, separations at the level of a mere block looked too trivial to bother about. The alley became outmoded, not functionally but because of the scale at which planning operated. Second, the backyard was increasingly thought of not as the household’s concealed work area but as its secluded retreat. Alleys, let alone ancillary residences inhabited by “different” people, would have rudely intruded on the popular image of backyard aspirations. Consequently, in such places trash hauled to the front curb for pickup regularly exposed the backside of the American Dream to public view. Virtues of the alley rediscovered The last quarter century has seen a return to finer-grained planning. New urbanists led the way in rediscovering the virtues of the alley for service and in showing how to use alleys without compromising the restorative ambience of rear yards. Second, following slightly later, ancillary dwelling or work units on alleys, almost always above garages, were reintroduced as a desirable possibility. Alleys are now widely accepted, and ancillary garage units increasingly so. The time has arrived to study larger mid-block insertions, both those based on historical models and new, accessed by alleys. Particularly in places where land values are rising and housing affordability is threatened, alley-accessed complexes of smaller dwellings offer an incremental step, beyond garage units, between single family houses and multifamily apartment houses. Both in new neighborhoods and as insertions in existing neighborhoods with deep blocks, mews housing should join the toolkit of modifications to standard center-block alley patterns. Classic mews housing has a split alley surrounding two rows of two-story units facing inward to a linear pedestrian courtyard. Two problems must be addressed from the outset: appropriate design for the climate, and the danger that the mews will become a place to which the poor are relegated rather than one to which many are drawn by convenience, seclusion, and scale. The mews court must be tuned to the weather of its region, affording enough space for wind ventilation without becoming a sun-cooked expanse. The potential social problem is best addressed by including from the outset a variety of sizes and types of units and encouraging unit alterations. Doing this will help forestall slippage into economic monoculture and only add to the informality and unexpectedness that are part of a mews’ appeal.