Advantages of green roofs
Green roofs have an invaluable aesthetic, practical, ecological and economic value. They create a biologically active surface that takes part in the air purification process and has an impact on the climate both in the place where they function and in its surroundings. In addition, they are responsible for better rainwater drainage and they look spectacular in every form, so they are added value for the overall effect of a building’s architecture. Additionally, intensive green roof systems create an area that can be safely used by people.
Green roofs as an “airbag”
Walls and roofs of buildings have the properties of heat accumulators. The resulting phenomenon is called the “heat island”. It involves an increase in the air temperature in agglomeration centres by at least 1 to 2°C. Sometimes the temperature in a very crowded city centre rises by as much as 10°C. At the same time, the air humidity decreases. That is why vegetation in such places is so important, as it creates a barrier to the greenhouse effect on the roof surface. This happens through the evaporation of water accumulated by plants and reflection of solar radiation. Such an “airbag” results in higher humidity and lower temperatures in and around the building. For example, a roof covered with bitumen tar paper heats up to 60-70°C in summer, while a green roof heats up to 25-40°C. These numbers speak for themselves.
Natural rainwater management
It is worth knowing that just a 2-cm layer of greenery can retain up to 60% of rainwater. Then, it evaporates, thus increasing the air humidity. In this way, the vegetation relieves the municipal sewage system, enriches the air with oxygen, which is so important for us, and at the same time reduces the content of poisonous carbon dioxide. For example, a green roof with an area of 15 m² is able to produce oxygen for up to 10 people per year, while absorbing 10-20% of dust and gases from the surrounding air.
Insulating and protective values of green roofs
Green roofs also constitute a great protective and insulating barrier for the facility on which their system operates. The green roof reduces outside traffic noise by reflecting and partially absorbing about 20-30dB. It is also an additional thermal insulation that protects the building against excessive heat loss and, on the other hand, against overheating. The vegetation layer also prevents damage to the roof caused by birds, wind and exposure to sunlight.
Architectural shaping of space
Green roof systems make it possible to hide installation devices located on roofs. The combination of the concept of greenery at different levels - from vegetation in apartments, on terraces and on roofs, through vegetation around buildings, enables the creation of homogeneous compositions. Shaped in a thoughtful and consistent way, green architecture distinguishes the building from the others.
A roof is the perfect place for greenery
Green roofs constitute an opportunity to regain the biologically active surface that has been lost in the urban space. As there is still little space for greenery in large urban agglomerations, it is an ideal way to arrange space, the purpose of which is not related to the local spatial development plan.