ORO Editions

Spatial diversity. Vasilikou and Nikolopoulou (2020) found that sequences of interconnected urban spaces of high diversity result in a "differentiation of thermal pleasantness" and more "thermally interesting transitions."

Design Guidelines

Provide tempered linkages between buildings; in buildings with thin plans, place circulation at one edge. Where possible, make the links open to the outdoor air, but protected from the extremes of summer sun and winter wind. Design overhead layers primarily to protect while ensuring that vertical layers connect visually.

Balance climatic protection with admitting desired forces, such as light and air to the adjacent indoor space. Awnings, arcades and building step-backs can all reduce winter wind down-wash effects on pedestrians. However, during warm periods such urban air flows can be a comfort asset. In their classic The American Vitruvius, Hegemann and Peets (1922) identify the arcade and colonnade as elegant means to unify a street while allowing individual buildings' their expression on upper stories. Simultaneously, "it consists in the charm and feeling of security enjoyed by the pedestrian" while being "sheltered from the rain and sun without being deprived of fresh air." Daylight reduction to adjacent shops can be addressed by tall arcades or clerestory windows above. Create outdoor linkages with tempered circulation in sites with building groups, such as educational buildings, university and corporate campuses and downtown areas. Connect the tempered pathways to buildings and to a variety of outdoor rooms, squares and open spaces. Designing one scheme that works in both cool and warm seasons is difficult. Sequences of more sunny/open conditions alternating with more shady/narrow conditions (squares vs streets for example) offer options and a seasonal reversal of where comfort is found. Outdoor circulation provides greater views of sky and landscape; locate paths to enhance this.

Bias in cool climates to block wind; admit sun as a second priority; ideally, do both. In cold places, the paths may be glass-enclosed, with or without conditioning. In cold Anchorage, Alaska, planners recommend sidewalk arcades rather than awnings or canopies because they "avoid obstructing sunlight or views along the existing sidewalk and can provide a more comfortable, sheltered transition space between the indoors and outdoors." They also recommend transparent roofs that allow sunlight to reach the sidewalk (Anchorage Planning Dept 2007). Design awnings to avoid shedding snow and rain drip lines on the sidewalk.

Bias in warm climates to admit breeze and create shade. Keep the vertical dimension open for airflow. Locate circulation along the edges of courts, or along building street edges, especially on the north edges of either (in Northern Hemisphere). Guidelines for designing a layer of Overhead Shades that can protect outdoor spaces and buildings from high sun is addressed in DeKay and Brown (2014). Hot climates suggest opaque overhead shade, roofs with smaller daylight openings or vertical screens for westerly sun. Alternately, locate pathways in narrow north-south oriented spaces or streets between buildings that can provide for shade from low-angle sun. Cover pedestrian paths with glazing in cool, snowy or rainy climates. Glazed streets, such as in shopping arcade buildings, can be used like atria both for lighting adjacent rooms and for providing light to plants and activities that occur in their climate-buffered space. Potentially, they have the additional advantages of increasing marketability, reducing conductive heat loss and gain in the building (Buffer Zones), providing winter solar heat gain (Sunspaces) and serving as a passive ventilation stack (Stack-Ventilation Rooms)—strategies found in DeKay an Brown (2014).

Refine with C3 Scintillating Sun, G3 Existential Datum, G4 Shades of Brilliance and C4 Inhabited Periphery. Help build G5 Pockets of Shadow, R5 Heliotropic Rooms, S5 Phototropic Catenation and S5 Ingress Transitions.