Maintenance tasks
Maintenance falls into a number of categories:
- Establishment maintenance occurs during the first one to two years after installation and is undertaken to fully realise the design intent and outcomes. For vegetation, this includes tasks such as pruning, weed control, and irrigation to ensure healthy and vigorous plant growth.
- Routine or recurrent maintenance includes regular works that are undertaken to ensure the roof, wall or facade is maintained to a minimum or required standard of appearance, functionality and safety. For vegetation, this can include tasks such as weeding, pruning, removal of leaf litter and, in some cases, mowing.
Cyclic maintenance is scheduled interventions at less frequent intervals that maintain infrastructure. It includes maintenance of the underlying building structure and of specific components of the green roof, wall or facade system. This may include infrequent pruning or other formative management of woody vegetation, such as coppicing, or annual treatment of decking or other hard landscape elements to maintain their safety and functionality.
- Reactive and preventative maintenance is undertaken when some component of the system fails suddenly, or shows signs of imminent failure. Failure may be due to a long-term problem that has gone undetected (such as blocked drains by tree roots), or sudden damage resulting from an extreme weather event (such as stormwater incursion).
- Renovation maintenance includes works that change the design intent. This may arise after a change of ownership of a building which instigates a desire for change, through to remediation of a design failure.
Some typical maintenance activities for green roofs, walls and facades are outlined in the table below. These are intended as a general guide only: each site will have its own specific requirements and some listed will be more relevant and/or specific to a wall, roof or a facade.
Common maintenance tasks
Maintenance objective |
Tasks |
Maintain planting design |
Plant replacement, infill plantings |
Maintain plant growth |
Remove waste plant material (leaf litter, prunings, weeds), inspect for signs of pests or disease and treat as needed, make seasonal adjustments to irrigation volume and frequency as needed, ensure adequate nutrition levels for plants; inspect after severe weather events (e.g. wind or heat) to look for signs of stress |
Minimise weeds |
Mulching, weed control |
Manage lawns |
Regular mowing, annual renovation |
Maintain trees |
Regular pruning, annual tree inspection, brace and support as needed |
Maintain climbing plants |
Annual or biannual pruning to maintain density and cover and to remove growth from fixtures (windows, drains). Rejuvenate to renovate habit and growth |
Rejuvenate climbing plants |
Vigorous pruning to renew stems and encourage new basal growth (every 5-7 years) |
Monitor plant performance |
Maintain records of plant health, vigour and coverage, pest and disease impact |
Maintain substrate |
Top-up of growing substrate may be required due to wind, rain or animal activity (check the depth of the growing substrate before any additions are made to ensure weight loadings are not exceeded) |
Maintain irrigation (and fertigation) systems |
Manually test and inspect the irrigation system regularly and monitor any automated systems (check volume of irrigation delivered, its frequency, substrate moisture content, and, for hydroponic green walls, nutrient levels in the water supply) |
Monitor plant nutrition |
Maintain a log of fertiliser additions and records of pH and electrical conductivity values before and after addition of fertiliser |
Maintain drainage |
Ensure roof drains are clear and functioning, remove dirt, litter and other deposits from drain inspection chambers, check plumbing hardware, check condition of filter sheet and deeper layers if necessary |
Maintain non-vegetated zones |
Remove vegetation from perimeter zones and around other equipment and fixtures |
Maintain wind protection features |
Check the condition and fit of protection systems |
Maintain safety systems |
Check safety anchor points for fall arrest systems, check access points, e.g. ladders and stairways, check electrical safety of power points, lighting and irrigation control system |
Maintain waterproofing |
Inspect flashings over waterproofing membrane terminations, inspect wall fabric for any damage from water, fertiliser or plants, conduct leak detection of waterproofing on a green roof – if possible |
Maintain other hardscapes |
Clean or oil decking or furniture, inspect green wall or facade support systems for any loose attachments or fittings |