Topic 4 Intensive Green Roofs
According to the German Landscape Research, Development and Construction Society (2018) «Green Roof Guidelines – Guidelines for the planning, construction and maintenance of green roofs»1,
- Intensive green roofs are significantly heavier constructions.
- Intensive greening may consist of perennials, grasses, flower bulbs, summer flowers and shrubs, in some cases trees, as well as lawns.
- They can be flat, height-differentiated or punctually constructed. They are comparable with ground-based open spaces in the possibilities of use and design diversity with appropriate equipment.
- The plants used place high demands on the layer structure.
- This type of green roof can only be sustained through intensive care, especially regular water and nutrient supply.
- The soil substrate layer can reach 500mm.
- Saturated (with water) intensive roof mass can reach 750 kg /m2 and even 1000 kg /m2.
- See also Module 4.
Intensive green roofs can most easily be compared to building a garden on a roof. They are usually multifunctional and accessible. They require more weight and a deeper system build-up.
The word ‘intensive’ refers to the amount of input required to maintain a green roof. As parks and gardens, they need frequent maintenance, just as a park or garden needs to be tended on a regular basis. The maintenance is regular and depends on the landscape design and the chosen plant material. Anything is possible from lawns, perennials, shrubs, trees including other landscape options such as ponds, pergolas and patios.
A simple lawn will need regular mowing and irrigation during summer, whilst a green roof with plenty of trees and shrubs may also need irrigation and attendance to the vegetation.
Intensive Green Roofs
HOFT (House Of the Flying Trees) – a house of flying trees in Riga, Latvia. It is a green world view, a tribute to the city’s history and the trinity of modern architecture. Gentle restoration of the historic façade, installation of trees as part of the building’s architecture, structural glazing as a mirror that reflects the surrounding historic building and serves as a podium for tree installation. As a volume that seems to say, “I’m not the main one here, I’m just giving the opportunity to enjoy the world outside and inside ”.
