The Borneo Sporenburg development lies in one of Amsterdam‘s former working harbors. The city and West 8 Urban Design & Landscape Architecture planned an urban development with a density of 40 dwellings per acre (100 dwellings per hectare).
The block is 79 feet (24 meters) deep and unites the two extreme edges of the site. One side looks out across the water, while the other is part of an intimate, urban texture of narrow streets. The back-to-back dwellings are built above an internal street — a parking solution that enabled use of the ground-floor level for residential functions, which results in lively neighbor relations. The units also have patios and roof terraces, which are used as private outdoor spaces.
Dwellings on the north side are oriented toward the water. With two-story glazed lower facades, they take advantage of the natural light and view. The south-facing dwellings are oriented toward the inner street. Their elevations have a more closed design to ensure privacy. They also have a roof terrace facing an alleyway, which accounts for the staggered frontage.
A key question when discussing narrow houses is — what is considered narrow? The answer is based on historic precedents, which have been influenced by site conditions, cultural traditions, and technology.
On Amsterdam’s Singel Street, for example, there is a habitable unit whose front measures 3.3 feet (one meter). This, of course, is an extremely narrow space, probably a leftover gap between two structures.
Analyzing a room’s dimensions to ensure its proper functioning is one process for determining the best width of a dwelling. Highway-transit regulations could also be a consideration. When prefabricated, a unit with a width ranging from 14 to 16 feet (4.3 to 4.9 meters) can be shipped from a plant to a construction site without a front- or rear-car escort. A wider structure would be more expensive to deliver.
The minimum width of a dwelling also depends on the creativity of the designer. Past designs show that a 12-foot (3.7-meter) structure built on one to three levels can contain basic amenities.
It can accommodate a living room and kitchen on the ground floor, two fair-sized bedrooms on the second, and two more rooms in the basement or attic. The wider the design, the easier it is to fit functions within it. For my purposes here, dwellings up to 25 feet wide (7.6 meters) qualify as narrow.
Narrow houses can be detached, semidetached (attached on one side), or attached on both sides to form a row. When constructed in rows, they are commonly planned as part of a multistory, multifamily, high-density project.
Since their introduction centuries ago, and even more so today, their attraction has remained their groundedness. Whether used by one or several occupants, the design offers easy access to a back or front yard. Unlike apartment living, where a number of occupants share the main door, parking garage, outdoor spaces, and hallways, narrow townhouses offer independence and privacy.
The trade-offs include the narrow width, which can restrict interior flexibility, and reduced natural light to middle units. Front and rear yards also tend to be smaller compared to those of detached dwellings.
When cost-effectiveness is sought, choosing a suitable type of dwelling is a high priority. With a cottage, for example, the cost is lowered by building two stories on a single foundation, reducing land and infrastructure expenses. Another option, known as the “stuck townhouse,” offers further savings by placing two-story dwellings on top of one another. The savings, however, depend on the size of the overall footprint. Choosing a narrow design for these building types would lead to further cost reductions.
An alternative to a narrow single-family building is a multifamily layout with independent dwelling units. This type is known as a duplex when split in two, and a triplex when used by three households. By combining the design attributes of the single-family with “the plex,” additional housing types emerge, such as the fourplex, which is essentially two attached duplexes.