Technical assessment first
Green roof weight varies with water and the chosen build-up. Have the structure, roof slope, drainage and waterproofing assessed. Not every existing or new roof is suitable without changes.
Maintenance belongs in the design
Ask what inspection and care are needed. Drains must remain accessible. Clarify who supplies and warrants the planting system, edges and waterproof layer.
Vegetation, rooflights and drainage on one roof
Consider planting together with rooflights, edges and drainage. Not every square metre needs vegetation, and maintenance zones must stay accessible. Ask which planting system is specified, what loading was used and who checks the waterproof layer. Include upkeep: who inspects drains and plants, and how is the roof reached safely? Selecting the option in the configurator does not replace this technical design.
Keep inspection points and drains accessible
Agree how the roof will be safely inspected and who keeps drains clear. Ask which areas around rooflights, edges and penetrations remain unplanted. Match planting to the waterproofing below. Keep maintenance instructions with handover documents so responsibilities for vegetation and the roof remain clear.