Even if a facade appears very simple, a lot of work goes into the design behind the scenes.
For a project to be successful, it will need to balance client expectations and the available budget and time constraints with what is possible on a functional level.
Here’s an outline of the elements that need to be considered when designing a green facade.
The individual client’s expectations and goals will define the project. It can be helpful to give each different aspect of the client’s goal a weighting to determine what is most and least important.
For example, one client may want a quick-growing climbing plant wall, while another may be more focused on the thermal aspects provided by the facade. Another still may want a green facade to create customer appeal, such as in a shopping centre.
Without a clear picture of what the client wants to achieve at the start, the project risks missing the mark.
Building and site assessments
What the client desires needs to be balanced with what is possible on the site in question. A thorough site assessment will help in determining the most suitable structure and installation methodology.
Considerations here include:
- The characteristics of the building – such as its height, size, aspect, any shadowing or reflection from nearby structures, wind forces, and load-bearing capacity.
- Access for work and equipment – multi-storey projects require the use of cranes, scaffolding, lifts and other large pieces of machinery and equipment. It’s important to assess how the site will be accessed and how it could impact on surrounding properties and passers-by.
Climate and environment
This includes assessing local weather conditions, rainfall, temperature ranges, sun direction, shading, and how the building’s height and / or local vegetation could impact on the finished structure.
In a green facade, plants may be grown from the base of the wall at ground level, in which case the soil may need to be assessed, or through a hydroponic system to deliver the required nutrients. In some cases, such as in very high buildings, the plants may be grown in containers at varying heights up the wall.
Options for plant selection include twining plants or vines (such as wisteria and honeysuckle), which work well with vertical steel cables, and leaf-stem climbers or tendrils (e.g. clematis) which are usually best with cross-hatch structures that allow them to spread outwards. The plants may need to be trained to attach to the support structure.
Adhesive-sucker and root climbing plants (such as ivy) should be avoided, as they can damage building walls.
Scrambling-type plants (winter jasmine for example) that don’t grow to tall heights may also help to avoid a ‘bare’ look at the base of the facade.
The plants selected will need to be matched with the local climate. Other factors to consider include how quickly the plants will grow to height, how much sun they need, their light and wind tolerance levels, and how drainage, irrigation and maintenance will be managed.
The need for expert consultations
A successful green facade installation involves input from a team of experts, including a:
- Project manager – to oversee the overall project and keep it within budget and time constraints.
- Structural engineer – for assessments of the site and determining the most suitable support structure and methodology.
- Horticulturalist – to advise on substrate, plants and maintenance.
- Irrigation consultant – to provide advice on the best methods and systems for irrigation and ways to recycle and reuse water.
For assistance with your next project, speak with Tensile Design & Construct here.