Green Walls: An Overview

By Ian Salamanca
Editor-in-Chief

This week i'm going to talk about a concept both myself, and the Sustainability Club of LATTC are fascinated by; Green Facades, Living Walls, and Vertical Gardens. We'll look at what those mean and how they differ, some substantial benefits of including them in your design, and some DIY methods in multiple scales.

Patrocínio House- Architectural Record "Record Houses 2013"

Types of Green Walls

Green Facade:

From: Flickr

This style of planting is reserved for climbing and cascading plants; Typically used to cover the structural elements, or the building's facade.  While many older buildings feature sprawling ivy, this isn't what we generally consider as a "Greenwall" today. Without proper consideration, the ivy can easily take over, damaging the building's structure-making maintenance and repairs difficult. Though some inherent benefits remain, this method has become obsolete by newer methods.

From: Freshdesignblog.com/

What is typically designed today, is a series of Cables, Wires and Nets, or Modular Trellis Paneling.  These both are feature a separation between the plant and the building, allowing massive plant growth with little-to-no worry of structural damage.

Modular panels:

These provide the designer to the freedom to organize and rearrange the plants to achieve their desired outcome.  Since they are standalone pieces, maintenance can be done with more ease, and adjustments are possible. These panels also are ideal for including a Biofiltration system (as discussed below) since the water and light can be fine tuned on a plant by plant basis.

From: Products.construction.com/ (JAKOB)

Cables:

These are useful when the plant is a fast growing vine, since they are strong enough to climb on their own. Since there is more space between each cable, it's best to have plants with dense foliage. The construction is pretty much as it sounds, cables held in place by structural anchors.  This style is obviously fairly rigid, so cable tension is important to consider during the maintenance stage.

From: Greenroofs.com/

Wire or Rope Nets:

Netting is needed when dealing with a slow growing vine, one that needs more support to keep climbing. This is created by running either steel cables or rope into a netting system, using similar anchorage as the cable systems.  This design is much more flexible, allowing more freedom of design.  Though some tension is needed in maintenance, not nearly to the extent as just cables.

From: Weyume.com/

Living Walls:
My personal favorite, as they can accommodate the widest range of plant species, including edibles which is known as Urban Agriculture.  Living walls could be made as modules, or static, it could be made from plastics, synthetics, clay, metals or concrete. They can be attached or could be freestanding, giving almost ultimate freedom of design.  Due to their complexity, they require not only more maintenance than the other two styles, but require the maintenance to be planned out in the design stage.  Since each species has it’s own needs and requirements, it is crucial to be aware of what they are and the best way of delivering them.  Living Walls are perfect for Biofiltration.

Modular Living Walls can be tailored specifically to the plants within the pieces, soils and nutrients already implemented in the planters.  Often times these can be pre-grown, allowing a more complete look upon completion.  Depending on the plant type, many of these modules can be installed inside the building since they are inherently self-contained.

Biofiltration

From: ManhattanPlant.com

"An ‘active’ living wall is intended to be integrated into a building’s infrastructure and designed to biofilter indoor air and provide thermal regulation. It is a hydroponic system fed by nutrient rich water which is re-circulated from a manifold, located at the top of the wall, and collected in a gutter at the bottom of the fabric wall system. Plant roots are sandwiched between two layers of synthetic fabric that support microbes and a dense root mass. These root microbes remove airborne volatile organic compounds (VOCs), while foliage absorbs carbon monoxide and dioxide. The plants’ natural processes produce cool fresh air that is drawn through the system by a fan and then distributed throughout the building. A variation of this concept could be applied to green facade systems as well, and there is potential to apply a hybrid of systems at a large scale."

-Passage From: Green Roofs for Healthy Cities: Introduction to Green Walls -  www.greenroofs.org

Benefits of Green Walls

From: RudeBaguette.com

While the benefits are numerous, the simple fact that it opens the possibility of vegetation in urban environments is enough for us to consider this a TRUE Sustainable Solution. We understand that there is no substitution for the natural world, and each new building we erect stamps out more of that world.  By bringing the vegetation back into the design we are lessening that footprint.

Inherent benefits

Each design will bring it's own advantages, however here are some of the basic benefits that most green walls can provide.

From: Commuterservicesfl.com/

Air Quality

Reduced Emissions- This one stems primarily from parking structures, where there are car emissions built up.  It's been shown that by including green walls into the design, the heat island effect can be drastically reduced.

Absorbtion of Carbon Dioxide, Noxious Gasses, and other pollutants- I was surprised to find out that plants can absorb many more chemicals than just Carbon Dioxide; Formaldahyde was a particularly shocking one.  By including Green Walls on the inside of a building, you can not only provide freshe clean air, but can actually filter the toxic elements.

From: Markiluxawnings.com/

Heating and Energy Efficiency

Reduction in both Direct and Ambient Temperature- Since the majority of the sunlight hitting the building is going to be absorbed by the plants, the amount of heat actually making it inside is much lower.  Without the ability to radiat outwards from the concrete it will actually lower the surrounding climate. This is beneficial to both building owner and surrounding neighbors.

Limits the movement of heat- By adding the extra barrier, green walls can better keep the heat they do have.  This is crucial when dealing with locations with drastically different summers and winters.  By better maintaining the temperature naturally, the building becomes more energy efficient.

Natural Forces

From: Plantsinaction.science.uq.edu.au/

UV Protection- Once again, the plants are absorbing the majority of the sun's rays (compared to same building without Green Walls) giving the buildings' finishes protection from sun damage.

Wind Disruption- While most notable on projects where the wall acts as the barrier (I.E. Parking Structure) where the wind is a direct influence to the inside of the building, this also happens when simply alongside the wall. They can mute the wind's effect to better seal windows and doors, and give upper-floor balconies better stability.

From: Sony

Noise Reduction- In a similar fashion, (to how it disrupts wind) plants are naturally acoustic blocking, and do wonders to mute the outside distractions.  A good example of this in practice is the Edmonton International Airport in Alberta Canada.  I would be interested in finding a recording studio that uses this technique.

Design Specific

Some benefits are based on things like (but not limited to): Plant type, Location, and Design.  The desired outcome is important when designing a green wall; maintanence should be an important consideration throughout the lifecycle. 

EDITT tower, Singapore.
From: Inhabitat.com

Asthetics

Since each design relies on the specific factors of it's location, it's pretty safe to say no two green walls are alike. This uniqueness allows a lot of freedom of design.  With replaceable, and arrangeable modular units the Green Wall becomes less of a structure and more of an art piece.  Since the various plants also have differences in texture, color and form, the possibilities are vast.  Green walls will become our flags of definition, in a world of reproduction.

Biodiversity

From: 33 Goddess Lane.BS

Depending on what was planted, there have been studies indicating that Green walls can bring about Biodiversity.  Migratory birds and bees have already shown interest in the close cousin, Green Roofs.  It is important to keep in mind that most of this research is relatively new, and specific recommendations have yet to be laid out. So if you are planning a green wall of your own, record your findings!

From: Sidewalk Sprouts.WP

Urban Agriculture

Possibly my personal favorite. By creating green walls that incorporate edible plant species, and doing so in an urban space, it will provide a much needed assistance to a problem of city life. The availabilty of fresh, quality produce for low-income areas; a simple step towards feeding the nation's hungry.

From: CGWV.com/

LEED Certification

While each project will produce it's own unique outcome, including Green walls can potentially secure up to 18 LEED Points!  This shouldn't come as a surprise since you now know, the buildings that implement these become more efficient. For more information please consult the LEED Standards, or the PDF located at the bottom of the post.

In Conclusion:

Not only are Green Walls good for your designs, but good for the environment and financially sensible. Sounds pretty sustainable to me! I'll leave you, for now, with a beautiful infographic, and a list of resources.

Be sure to follow us later this week as we bring you more about this, on Wednesday with some case studies, and on Friday with a curated collection for your weekend! If you enjoyed this please share it, and be sure to FOLLOW us for updates!

From: Hotel-Latour.co.uk/

Resources:


Australian based Blog post outlining some amazing benefits: http://www.yourhome.gov.au/technical/fs513.html
Super helpful PDF that helped structure this post: http://www.greenscreen.com/Resources/download_it/IntroductionGreenWalls.pdf