Building Physics traditionally focuses on the effects on and in a building. With the increase in the number of high-rise projects in the urban environment, the 21st century introduces a new aspect in the building design. The physical impact of a building on the environment is increasing. Large glass surfaces provide for, potentially undesirable reflections . Buildings higher than 30 meters have considerable influence on wind speeds at street level and shadow effects lead to a reduction in daylight to surrounding buildings. An environmental test provides insight into the situation that is to be expected around a building and formulates an opinion whether further investigation by using wind tunnel tests or computer simulations is advisable.
In the Netherlands, no legislation which impacts on the physical environment are implemented. Since 2006 there is the NEN 8100 standard, which prescribes an environmental study for wind conditions in projects with building heights exceeding 30 meters. Also, the larger cities each have their own policies when it comes to high-rises. The past few years one has been working hard to launch a European standard, but for now this is not at hand. However, a sustainable project always takes into account aspects that are not yet regulated by law. Not being able to reach the revolving door of a nursing home because of headwinds created by flow along the building or a underpass where cyclists cannot safely pass because of strong drafts are supposed to be undesirable.
Condition of light
A (high-rise) environment, where many continuous glass surfaces are present, causes next to strong varying wind conditions, also more fluctuation in the light on the Street. Glittering on the sunny side of a building may cause thermal discomfort of the pedestrians. Reflections of other buildings on the shady side of other Building may cause visual discomfort. Here too, unsafe situations like temporarily blinding of a motorist cannot be ruled out. Awnings, recessed frames, a special coating and intervals in the glass surface may limit the influence and their subsequent effects. The shadow effect of a building however is also not desirable at all places. Surrounding buildings may be partitially stripped of sunlight and therefor require additional measures to meet the health and safety – requirements. In New York skyscrapers were realised according to the classic pie shaped model, in which a 3 to 5 stage building space is maintained between the buildings in order to get sufficient daylight at street level. Do you want to know if your plans are environmentally friendly ? We will evaluate the project conditions and advise you about a possible plan of action.