Green roofs

Green roofs


A green roof can use as a design element; either as a contrast in a dense urban environment or the roof can fit into the surrounding green landscape.

Modern green roofs are becoming more prevalent, and with good reason:

Positive effects of green roofs.

  • Green roofs have a positive impact on urban landscapes by utilizing the potential in creating recreational and green areas in an urban-intensive environment. They create a natural environment with flora and fauna that not only excites visual interest, but the very presence of greenery has been found to reduce stress.
  • Rainwater management. Green roofs have proven to be an effective strategy regarding both the quantity and quality of stormwater run-off. Extensive green roofs can retain 85% of the maximum rainwater run-off in the first few hours of a rainfall event and can reduce total runoff by 60%. By delaying and reducing stormwater runoff, green roofs reduce the risk of flooding and overflow, which reduces the pressure on the existing sewage system. (Source: Moran 2004).
  • Noise reduction. Green roofs reduce both internal and external noise. The higher the density, the better the sound proofing. Green roofs are particularly useful at the dampening sound, especially at low frequencies. An extensive green roof can dampen sound inside the building by 40 dB, while an intensive green roof can reduce sound by 46-50 dB. (Source: Peck).
  • Durable construction. Green roofs can extend the life of the roofing membrane, as the membrane-protected from heat and UV rays.
  • Indoor climate A green roof can contribute to a better indoor environment, as the growth insulates the roof and ceiling from overheating due to the sun’s rays. Green roofs also reduce air pollution levels by lowering the extreme summer temperatures.
  • U value. Green roofs provide a better U-value than a traditional roof.
  • Operation and maintenance: A well executed green roof helps to reduce maintenance on the ceiling, as the growth layer, protects the roof membrane. Well, drained roofs with moss and herbs can survive for long periods without water, while the weeds just wither and die.

While the ceiling is growing, a water-retaining drainage layer must be installed, which, depending on the roof’s slope, can be in the form of nonwovens, netting or trash plates.
If the slope is over 10 degrees, the green roof secured against sliding; e.g. in the shape of a reinforcement mesh or other frictional underlay.

Advantages of the inorganic materials in the roof

To install a green roof is not always without problems. The general attitude of both Construction damage Foundation, Danish Construction Association, and the Danish Building Research Institute is that the vast amounts of water, which accumulates in the green roof, can cause moisture problems.   Construction damage Foundation advice against makes green roofs directly on top of wood structures.

SkanDek consists entirely of inorganic materials and therefore rot and mold cannot come into the element, because of moisture problems. It makes SkanDek most suitable substrates for green roofs. As mentioned, a well did green roof also for smaller operations and maintenance on the ceiling when the growth layer protects tag septum. SkanDek is also available in an exclusive UV-resistant roofing membrane with root barrier specially designed for use as substrates in green roofs. During tag growth must also lay a water-retaining drainage, that depends on the ceiling slope can be in the form of nonwovens, netting or draining boards. If the inclination is beyond 10 degrees, have green roof often protects against slumping, for example in the shape of a kind of mesh or other friction in the substrate.


Sea West, wellness and swimming pool. SkanDek elements with intensive sedum grass built as a “duo-roof.”

Two types of drainage layer, which laid on top of the roof membrane, under the growth layer. SkanDek often uses plastic trays on low roof inclination, while the plastic network is using the large slope.


A green roof can combine with solar cells.