Green roof design

Once regarded as a marvel, the various types of green roof are now a useful and striking element of landscape architecture. These green islands created on roof slabs meet both the technical requirements of architecture and the ecological demands dictated by nature.

A dense green carpet of sedum on an extensive green roof

The most common type is the extensive, low-maintenance green roof, which can provide the living conditions succulents need with a build-up just 10 cm deep.

A more recent trend is the biodiverse green roof, which offers a green oasis to plants and wildlife alike amid the concrete jungle of the city.

Ornamental grasses and flowering pinks on a biodiverse green roof

Intensive green roofs can offer a complete garden experience in the most unlikely places, with a stunning wealth of forms and colours.

Even the simplest green roofs deliver the benefits that have made this landscape solution such a popular choice today:

  • reduced temperature fluctuations both below and above the green roof
  • protection of the waterproofing against UV radiation and physical damage
  • retention of rainwater, easing the load on the drainage system
  • improved thermal and acoustic insulation of the structure
  • lower pollutant levels in cities, as the planting binds airborne dust
  • better operating conditions for rooftop plant and equipment thanks to less dust and lower temperatures
  • a habitat for plants and, in some cases, animals
  • higher permitted site coverage, as green roofs can count towards the green space index

Contemporary green roofs have a similar build-up whatever their type; the differences lie in the technical properties of the layers:

  • a protection fleece runs above the waterproofing (a separation fleece in an inverted roof build-up)
  • the drainage board stores water and drains away the excess
  • a filter fleece keeps the growing medium in place
  • the ‘soul’ of the green roof is a growing medium matched to the needs of the planned plants (not natural soil)
  • the vegetation, made up of a selection of plant species and cultivars suited to the conditions

For green roof design and coordination, we offer:

  • design of extensive and intensive roof gardens and roof terraces
  • consultation with garden designers and architects on creating extensive and intensive roof gardens and roof terraces
  • feasibility checks of green roof designs and material quantity calculations
  • development of alternative solutions