Archatrak Inc. |
FRP Elevated Green Roof Trays
‘Extensive’ green roofs are typically defined as having growing media less than 8'' deep, use small, low-growing plant species such as succulents, require minimal maintenance and relatively low water needs.
A modular tray system filled with 4''-6” of growing media and plantings is generally the simplest and most versatile means of creating an ‘extensive’ green roof . But in many cases there’s a need to elevate the planter trays to cover service pipes, electrical conduits and surface irregularities, to raise the plantings to match the height of paved areas, or to correct for the slope on the rooftop.
Fiberglass grating panels supported by adjustable height pedestals undoubtedly offer the most effective and versatile means of supporting raised planter trays. The fiberglass panels not only provide a solid base for the planter trays, but can provide support for pavers set among the plantings – porcelain, stone or concrete. Expanded polystyrene (EPS) foam is combustible and labor intensive to install while concrete pavers are extremely heavy and may exceed roof loadings with filled planter trays.
Some of the other benefits of using fiberglass grating panels to elevate and support an extensive green roof tray system include:
- Less pedestals needed c.f. concrete pavers
- Large panel size (typically 4' x 8') ensures much faster installation
- Superior wind uplift protection – interconnected panels create a continuous surface
- Allows space for irrigation pipes under the plantings
- Water drains freely via the open grid structure
- Minimizes weight loading – just 2.5 – 4 lb/sq.ft. (depending on panel thickness)