Green facades can range from complex systems for multi-storey buildings, with plants growing in containers at different heights, to simpler systems where the plants grow from the ground, allowing inexpensive installation of greenery on low-rise buildings.
Wall protection and different facade treatments
Waterproofing treatment of the wall is not required for green facades. It is important to select plant species with a growth habit that will not damage the fabric of the wall. Some species with adventitious roots or scrambling stems can damage the building fabric over time, such as Common Ivy (Hedera helix). However, self-clinging climbers are exceptionally well suited to many vertical building surfaces, particularly old stone structures or those with minimal exposed mortar, and have lasted a long time without negative impacts on the building fabric.
Plants can damage buildings by physical and chemical means, over timescales of centuries. Damage can be superficial, causing only aesthetic changes to the facade, or more structural damage may result, usually over much longer time periods. If in doubt, choose a green facade where the plants are grown on a support system that is installed separately from the building.
Support systems for facades involving plants that have tendrils or twining stems (see here) may be made of plastic, timber, metal, or stainless steel cables or cable mesh. Design of the support system must consider the intended lifespan of the facade, the growth habit of the plant species, and how spacing and offset from the wall can help to provide the desired end result. .
For containerised systems, plant species choice and the spacing and volume of containers are critical for establishing effective facade coverage. Specialists in green facade design and installation can provide advice on the most suitable system and the best construction approach.
Wooden trellises are prone to damage by weather and plant growth and many plastics become brittle over time with ongoing exposure to UV light, heat and cold.
Metal systems have the longest lifespan and require less maintenance. Stainless steel cables and trellis are low maintenance and have a long lifespan and probably offer the greatest flexibility to suit a variety of plant species and wind loads. Steel nets and mesh provide additional options, with closer ‘weaves’ than horizontal and vertical cabling.
Support systems are suitable for very structured arrangements where greening has to be maintained away from windows or because of the other building constraints, such as the geometry of the building facade. A facade support may provide aesthetic appeal when the plants have not yet grown to full size and in winter where deciduous climbing species are used. Support systems can be separate from a building and used to create a green facade for privacy or shade.
For more on green facade construction see the ‘related pages’ menu on the right.