Commercial Roof Garden
Commercial Client’s Roof Garden
Upgrading a well-known client’s roof garden space
“ Due to the location and associated load bearing considerations, Willowbrook used lightweight bulk materials, with moisture retaining qualities for the planting medium. ”
The recycled plastic planters contained a liner with drainage holes in the base. The bottom third of the containers were filled with a terracotta 8-16mm. LECA (lightweight expanded clay aggregate) an inert, bulky material with moisture retaining qualities.
A landscape membrane was installed over this to separate the LECA from the compost above. The lightweight planting medium was a blend of sandy loam, coir, PAS100 Green compost and LECA. All the planting was 10-30 L. pot grown for instant effect.
- The loam itself complies with BS 3882(2015) and is screened to 10mm.
- The Coir is ground coconut husk from Sri Lanka (Peat substitute).
- PAS100 Green compost (Publicly Available Specification) – industry standard for organic material, screened to 10mm, adding nutrients to the mix.
- LECA 4-10mm. is incorporated into the compost to reduce bulk density and enhance drainage characteristics.
- A mulch layer of terracotta LECA completed the project, providing an ornamental finish with moisture retaining properties.
- An irrigation system ensures that the planting receives adequate moisture throughout.
The gallery below shows the planters and a section of the completed commercial roof garden space