Green wall

A Green wall, also known as a living wall or vertical garden, is a wall partially or completely covered with vegetation including a growing medium, such as soil or a substrate. Most green walls also incorporate an integrated water delivery system because they require regular irrigation to sustain the plants. Green walls are found both outdoors and indoors in both public and private spaces, and they serve multiple purposes including aesthetic enhancement, air purification, and the promotion of biodiversity in urban areas.

History

The concept of the green wall dates back to the hanging gardens of Babylon, one of the Seven Wonders of the Ancient World. However, the modern green wall with integrated water delivery systems was invented by Stanley Hart White in 1938, a professor of Landscape Architecture at the University of Illinois. The technology for green walls has evolved significantly since then, with advancements allowing for more sophisticated irrigation systems and a wider variety of plant species that can be supported.

Types

There are primarily two types of green walls: exterior green walls and interior green walls.

• Exterior Green Walls: These are installed on the exteriors of buildings and can range from a few square feet to entire walls. They help in reducing the overall temperatures of buildings, thus reducing energy costs for cooling. They also improve the outdoor air quality and help in reducing the urban heat island effect.

• Interior Green Walls: Installed inside buildings, these walls are often used as living art or to improve indoor air quality. They can help in reducing Volatile Organic Compounds (VOCs) and increasing indoor oxygen levels.

Benefits

Green walls offer numerous environmental, social, and economic benefits. Environmentally, they contribute to biodiversity, reduce the urban heat island effect, improve air quality, and manage stormwater. Socially, they can improve well-being, reduce stress, and increase worker productivity when installed in office spaces. Economically, green walls can increase property values and reduce energy costs by providing insulation.

Challenges

Despite their benefits, green walls face challenges such as high installation and maintenance costs, the need for a constant water supply, and potential issues with water damage and mold growth. The choice of plants is also crucial, as they need to be suitable for the wall's orientation, the local climate, and the available light.

Installation and Maintenance

The installation of a green wall involves setting up the frame, which holds the plants, the irrigation system, and the growing medium. Maintenance involves regular watering, fertilizing, and pruning to ensure the health and growth of the plants. Advanced systems may include automated irrigation and nutrient delivery systems to reduce the labor required for upkeep.

Examples

Notable examples of green walls include the Musée du Quai Branly in Paris, France, designed by Patrick Blanc, a pioneer in green wall technology, and the CaixaForum Madrid in Spain. These examples showcase the integration of green walls into modern architecture and urban landscapes.