The wider Amsterdam Metropolitan Area will radically change in the next decade. Climate change forces cities to rethink the design of public spaces as heat stress and heavy rainfall has rapidly gained importance in urban design. Heat stress also increases the demand for cooling, which could negate strides made to reduce the energy consumption of buildings.
In the wake of the Covid-pandemic, people are spending more time at home, and the fine line between a house and office has blurred. During the pandemic and lockdowns, people noticed the sudden quietness and the lack of noise pollution. Unwanted sounds can make people ill, as noise increases the risk of heart diseases, correlated to long term exposure to stress.
“Working and living at the same place might make people more prone to noise pollution. This is especially the case in cities, with the humdrum buzz and sounds of traffic and human sounds. Lower traffic volumes during lockdown literally cleared the skies, increasing awareness about air pollution and how it affects our health. The pandemic has made us realize that alternatives are possible in respect to the way we organize our cities.”
The Amsterdam Metropolitan Area is also on the eve of a housing boom, with a demand for more than 200.000 newly built dwellings. About 80.000 houses will be built in the proximity of Schiphol Airport, areas where noise and pollution levels are traditionally higher than elsewhere. With a lack of space, the availability and allocation of land is constantly contested. Spatial claims are often in conflict with the needs of others, like noise and emissions from air- and seaports and quietness in residential areas.
Make Some Noise
In Make Some Noise we study the impact of the built environment on the propagation of aircraft noise and air pollution. Simultaneously, we look at crossovers between measures for noise abatement and their impact on heat stress and energy-consumption. Instead of conflict, we focus on ways to synergize interest that seem juxtaposed at first sight.
Buildings and green walls as noise barriers
Buildings can act as large noise barriers, yielding a noise shielding effect, also for aircraft noise. The extent of shielding depends on the angle at which sound waves hit a building. The angle is location specific, varying with the altitude and horizontal distance between aircraft and location. Sound levels around the buildings are subject to the shape, height and cladding, and distance between facades. Porous materials, like green walls, are examples of noise absorbents, at least in theory. Green walls can also contribute to the removal of fine particulate matter from the atmosphere.
Wind flows are influenced by buildings, influencing where, and in what quantities, particulate matter settles. Thermal isolation does not always limit noise ingress through facades, while lots of existing houses will have to be thermally insulated during the next years. Based on computational models and measurements, the shielding and abatement potential around buildings can be predicted, supporting urban designers and municipalities to design better areas close to airports. It also helps developers and architects to face noise-sensitive rooms, like bedrooms, towards the shielded sides of buildings. This is an example of a simple architectural intervention with serious health implications.
Green and blue measures to combat noise
Noise annoyance is not absolute but the outcome of context and person specific conditions. From an evolutionary perspective, sound is a trigger that mobilizes the body. Whether the trigger leads to nuisance depends on the environment and personal circumstances of the person exposed to the sound(s).
Laboratory studies have showed that people in urban environments with lots of trees and moving water see traffic noise as less unpleasant. This effect relates to visual and auditory masking effects evoked by trees and moving water. However, water droplets and trees are also valuable assets to combat heat stress, while simultaneously introducing more temporary water storage capacity.
“Noise measures can be linked to climate adaptation, with each penny spent paying off twice. Computer models can support the design process to predict where trees and water features are deemed most effective, for both the soundscape and local climate.”
Data collection to improve quality airport areas
The overarching aim of Make Some Noise is to develop a comprehensive toolbox supporting (urban) designers, municipalities, and developers to improve the quality of areas around airports. In this context, quality means less noise, less pollution, climate-adaptive and a lower demand for energy. Thereby, we focus on the impact of urban geometry, façade cladding and the design of outdoor space.
By linking and amending computational models, the ambition is to improve our understanding of the compatibility of single or combined measures in the light of noise, climate, pollution, and energy. However, computer models are fed with ‘real’ data, meaning that data collection in the real world is essential. The data is needed to teach algorithms and serve as benchmark for the output generated by computational models.
Field and living labs
Contrary to living labs, field labs are full-sized research facilities without occupants. In a field lab environment, innovations are tested before launched into the ‘real’ world. Noise measurements require a certain level of control, which is why a field lab environment fits in well with the ambition to validate and improve acoustic calculation models.
Alongside the field lab, our ambition is to work towards living labs in which innovations are implemented, and further developed, together with citizens and local communities. Living labs are a stellar opportunity to explore the efficacy of measures, both physically as behaviorally.
We are currently collaborating with the municipality of Haarlemmermeer and various other regional partners to draw up plans for the field and living labs. A first project under the umbrella of Make Some Noise is a climate sensing study, in which we collect weather data in low density and rural residential areas. Results from this study will be used to calibrate urban climatic models.