Roof/Sky Garden
Introduction
There are generally 2 types of green roof – extensive or intensive green roofs. Extensive green roofs are lightweight with shallow soil substrate and are designed mainly for ecological benefits and aesthetic. It requires minimal maintenance of once or twice a year as plants selected are self-generative and of low maintenance.
On the other hand, intensive green roofs (roof gardens) are associated with added weight and designed to be accessible, thus suitable for recreational use. It has more intensive planting ranges from ornamental lawn, shrubs to trees. It requires frequent maintenance of watering, weeding, fertilising, mowing, etc1.
Green roofs have benefits such as improved thermal performance and aesthetics, reduced urban heat island effect and stormwater runoff, creation & preservation of habitat & ecological biodiversity, etc. These benefits can only be maximized with proper maintenance2.
Maintenance of rooftop greenery should be conducted such that the quality and performance of the greenery is maintained and it does not compromise the performance of the rooftop. It should prevent or identify and rectify problems to rooftop greenery such as falling plant debris, plants failing, overgrown plants, roots compromising roof systems, water ponding, mosquito breeding, etc. For ease of maintenance, design and access to green roofs should be well-considered to provide safe and effective maintenance1.