AN INTRODUCTION TO GREEN WALLS:

LIVING WALLS

Mehdi Rakhshandehroo Faculty of Design And Architecture, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia

Abstract

• In the challenge of urban expansion and environmental preservation, sustainable development is a significant response to our century’s requirements. Although vertical greening (green walls) are not a new concept but flourished during the last decade as one of the approaches to sustainability. Vertical gardens, vertical farms, balcony gardens, containers or planter boxes greening, green or eco-buildings, wall planters, and green envelops are all different types of green walls. Planners and designers can look for enhanced solutions where the façades are more than tinted glass barrier; greening the building envelope with vegetation can be used as a mean to restore the environmental conditions in urban areas.

• Environmental benefits of green walls have been proven on both new and existing buildings; they can be applied for insulating against environmental impact, mitigating the effect of urban heat island, increasing biodiversity and ecological value, outdoor and indoor comfort, air quality and social and psychological wellbeing. Green walls are categorized into living walls and green facades; living walls which are the subject of this presentation categorized into passive and active systems, Mur-Vegetal and Landscape walls according to their systems and growing method.

Introduction • Since 2000 years ago climbing plants have been manipulated to the main

building façade.

• They may be applied as indoor or outdoor systems.

• The selection of plants and soils should be different according region and

climate.

• Selected plants roots can grow in: o The wall material directly

o Ground

o Modular panels attached to the façade

Source: http://makinglewes.org

Benefits

Environmental benefits include:

• Aesthetic enhancement

• Pollution filtration

• Requisition carbon dioxide

• Decrease in fine dust levels

• Cleaning the air

• Photosynthesis

• Serve as an “extra insulation” to

decreases the wind flow and heat

radiation

• Blocking of the direct sunlight

• Energy saving

• Sound reduction

A bridge in France,(Source: http://urbantimes.co)

• Green walls (vertical greening)

can be categorized According to their

systems and growing methods:

1. Green façades (direct and indirect

system)

2. Living walls (passive, active, Mur-

Vegetal and landscape wall)

This presentation will discuss

different issues of living walls.

Living wall, Source: http://makinglewes.org

Living walls

• Living wall systems (LWS) are built of modular panels, each part holds its

own soil or artificial growing medium

• In a comparison to green facades most of these systems:

o Need more detailed design

o Have complicated layers, supporting materials and mechanism of water and

nutrient

o Are more energy consuming and difficult to maintain

o Apply a variety of plants, mostly evergreen plants as ferns, low shrubs, perennial flowers

and even edible plants

o Offer much more creativity and aesthetic

• The durability of living wall systems are important to take into account:

o Living wall systems based on planter boxes last more than 50 years.

o Living wall systems with panels based on felt layer have an average life expectancy of 10 years

Living walls based on: a- planter boxes, b-foam substrate, c- felt layers, (source: R. Sharp 2008)

Passive living walls

• They are mostly applied in modular

systems.

• As modular systems are usually pre-

grown, can provide an immediate green

effect.

• They should be supplied with irrigation

system along the wall at different levels

• A waterproof substance separates the

building wall and system to prevent wetting

problem.

• Fertilizers, emitters, Insulation and lighting

systems may be required.

Living walls components: 1- Panels, 2- Non-soil structural growth

medium,3- Plants,4- Remote irrigation/fertilization system,5- Stainless

steel frame, (Source: Gsky.com)

Passive living wall, (Source: La societe Green wall)

Active living walls • Apply a forced air flow through the subs-

tract.

• It is intended to be integrated into the

building’s infrastructure and designed to act as bio-

filter indoor and ecological air conditioning system.

• Rich nutrient water recirculated from a

manifold.

• Two layers of synthetic fabric sandwich

the roots mass.

• The plants absorbs carbon monoxide and

produces cool fresh air by a fan that pulls

environment air through the system and distribute it throughout

the space.

• Where this system is integrated with the

building's air condition, reduces energy

consumption.

Active living wall, (Source: GM Canada and air quality solution)

Mur-Vegetal

• Mur-Vegetal is an exclusive type

pioneered by Patrick Blanc who is a

French botanist specialized in plants

from.

• This system consists of two layers of

synthetic fabric with several pockets

that physically keep growing media

and support plants.

• It is held by a frame and supported by

a waterproof substance against the

building’s main wall.

• The irrigation system that propels,

water from top to down, also

distribute nutrients to the plant’s

roots.

Mur Vegetal (Source: http://flickr.com/photos)

Landscape walls

• Landscape walls are an

evolution of landscape berms.

• They are:

o Normally sloped against the

vertical barrier and have the

major functions of slope

stabilization and noise

reduction.

o Constructed from some stacking

material made of concrete or

plastic with spaces for plants

and growing media. Landscape wall, (Source: http://www.herculesmfg.com)

Thank you

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