Outdoor Comfort Great Outdoor Space – Great Cities
“The difference between a mediocre city and a great city are great parks and a fabulous outdoor space” 1 But what makes a good outdoor space? Apparently, that it is built to a human scale and is adaptable for various uses, such as recreation, markets and social gatherings.
But who is responsible for the outdoor space? The book “Learning from New York” 2 explains that careful, thoughtful city planning and governance, as well as engaged citizens, can create fabulous outdoor spaces in streets, parks and squares. In other words, a city’s planners and politicians are not the only ones responsible for outdoor space, its citizens are too.
I like this place in my city
Totally liberating streets from car traffic is still a good strategy to reclaim useful space for the people. A car-free space can be used more democratically and with greater flexibility than one is car-filled. This strategy was explored in an experimental virtual dialogue led by Aedes at the FutureCityLab 2012 conference in Berlin. At the Aedes exhibit “Cities in Progress – Please do (not) disturb” we posed the unfinished sentence: “I like this place in my city, because of …” and got tremendous feedback. A selection of interesting articles from this exhibit can be found online.
Many characteristics of well-loved, outdoor, urban spaces are universal. A lack of cars and a high probability of accidental or planned encounters with other people are important for us. These outdoor spaces should also be designed for use under various weather and climate conditions. They should have, as a minimum, sunlit and shaded areas, rain and wind protection if necessary, good ventilation on hot days, and furniture that is multi-purpose and is composed of inviting materials and finishes.
Climate Change and Outdoor Space
In the building sector, saving energy is traditionally related to building end-uses. We see that energy-saving regulations and codes focus primarily on individual buildings, their systems and their energy performance. The space surrounding an individual building is typically only considered with respect to the daylight or shading potential that it provides. However, the urban outdoor space can offer so much more; this is particularly important given the global problem of climate change.
We must ask ourselves: “How can urban outdoor spaces be used to fight against climate change?”
In summer 2003, a heat wave in Europe led to intolerable conditions for residents and tourists alike. Cities, especially Paris, were severely affected. Paris covers only half the land area of Berlin or London, but has a higher proportion of impermeable surfaces. These surfaces store more heat than green spaces and release this heat back into a city; these surfaces and conventional buildings create urban heat islands. However, green spaces can counteract the effects of urban heat islands through shade and evapotranspiration. The temperature in the middle of a green space greater than 1 hectare is at least 1°C cooler than the surrounding built environment. Studies show that having 10 % more urban green spaces around the world could delay an overall global temperature rise until 2080.
Design for Outdoor Comfort – Carefully Planned Green and Blue
Outdoor comfort can be improved by introducing passive and active strategies that are tailored to local climatic conditions. Outdoor comfort is influenced by many environmental parameters such as solar radiation, infrared radiation from the surroundings and from the sky, air temperature, humidity and wind speed. Manipulating these parameters, and considering user clothing and activity levels, allows outdoor comfort to be assessed and compared between different scenarios.
Realized projects prove that simulation and planning tools are becoming more and more precise. Such tools allow climatic improvement measures, such as wind protection and shading, to be studied in detail. Therefore, improvements to “The Green and Blue” – parks and public realms with softscape and water features – can be precisely designed prior to construction or renovation, with guaranteed results. Furthermore, spots within a single outdoor space/property can be adapted for different activities (eg. sport vs. sitting).