Design and planning of a green roof, wall or facade must incorporate an understanding of how the system will be maintained. Buildings owners and property managers need to understand what is involved in maintaining the roof, wall or facade and must be committed to managing it, otherwise the benefits outlined earlier in this document may not be achieved.
The systems, or assets, created must not exceed the skills, technologies and resources of those who will be given the responsibility for their maintenance. There are examples of green roofs in Melbourne that have been designed which require complex horticultural management, but the management has fallen to contract staff with no specialist expertise in green roofs, and the landscapes begin to deteriorate. This can result in user complaints and/or the need to replace an asset prematurely, which is inefficient and unsustainable both economically and environmentally. It may be that the green roof, wall or facade provider is best placed to undertake on-going maintenance on a contract basis.
The person or team with ultimate responsibility for management of the project/property must be clear about maintenance objectives and their capacity to undertake them with available resources. All design options proposed must be fully evaluated in terms of the maintenance they will entail.
Including ongoing maintenance costs is an important part of the design considerations, especially from the point of view of the client, or asset owner. To determine the ongoing maintenance requirements of a green roof, wall or facade consider engaging a consultant or contractor with relevant experience. Advice can be provided on the resources needed to maintain different design options and the likely expenditure needed to maintain the materials used. For large commercial projects, a maintenance impact statement can be provided by the landscape designer. Alternatively, specify maintenance objectives and standards early, so that the designer has these in mind to start with. More information on Maintenance is available here.
Consideration may be needed for renewal or removal of a green roof, wall or facade, especially where a temporary or short-term installation is proposed. The Melbourne Central shopping centre green wall was designed as a temporary installation, however with various interventions its life was extended for some years. Ultimately it was dismantled due to high maintenance costs for a wall in a position with very limited light. Although roofs, walls and facades can, of course, be designed from the outset to last for decades, in some cases they will be designed for a limited lifespan and therefore the opportunities for renewal or process for removal should be considered in the design stage.
- Site analysis
- Design objectives
- Drainage and irrigation
- Maintenance planning
- Sourcing skills, expertise and information
- Cost considerations
- Planning, regulation and local laws
- Building rating schemes and planing assessment tools
- Plant selection
- Plant establishment
- Urban food production
- Green roofs for biodiversity