A green wall or roof is an urban and architectural element in areas that otherwise have no natural green context.

A green facade has the ability to transform the outer skin of our cities into a living landscape, allowing the concrete and brick to become environmental assets themselves.

As consumers we place a high value on areas that incorporate pockets of green. We can create more desirable places to live and work by cloaking some of our urban landscape with a living tapestry.

This urban greening not only represents visual enhancement, it is also an investment – an investment into the building, into the environment around it, into the habitat it can support and the energy it expends.

The psychological benefits of going green

Greenery has been shown to have a positive impact on our mental health. The importance of a green aspect in healthcare settings has a raft of literature supporting it. The more we have access to green space – even if it is just a view from the window, the happier we feel.

Plants help filter particulate in the air

The leaves of climbing plants provide a large surface area. Leaves are able to absorb and filter out dust and pollutants, they can trap carbon dioxide and are able to produce oxygen – vital for the wellbeing of our environment.

Green walls increase humidity levels

In cities there is a fast runoff of rainwater into the sewage system due to hard surfaces like concrete. Because leaves hold water on their surfaces this increases humidity.

Energy conservation

A green wall on a building helps with cooling of the building in the summer – this is due to the leaves providing shading form the hot sun, therefore reducing the solar glare on the building. An additional cooling effect is provided by evaporation and transpiration. Evergreen species trap a layer of air against the façade which reduces convectional heat loss offering a degree of insulation during winter.

A green wall can protect and potentially even extend the life of the architectural surface beneath it. The harmful effects to stonework of acid rain, UV light and wind can be reduced by a covering of leaves.

Encouragement of wildlife

A green wall encourages urban biodiversity within our cities. Climbing plants can provide a nesting habitat for birds and can be important sources of food for them. Insects and bees will also be attracted. Green facades can compensate to some degree for the inevitable loss of habitats by urban developments, encouraging flora and fauna to return.

Noise reduction

The addition of a green wall to a building is very effective at absorbing noise from the surrounding area, contributing towards a more pleasant environment.

Climbing plants have developed a variety of different climbing mechanisms by which they attach themselves to the support provided.

Broadly speaking, there are the climbers that are self-clinging or ones that need support. There are 3 main types of support that can be provided for these species; a trellis or framework made up of horizontal and vertical elements, just vertical supports or just horizontal supports. This will depend on the type of species chosen and the limitation of the design.

There are 4 main categories of climbing plants;

1. SELF-CLINGING CLIMBERS

This includes climbers that use lateral shoots with glandular discs that adhere to any surface, and adventitious root species that can grow over large distances without any means of auxillary support. Boston Ivy (Parthenocissus tricuspidata) and climbing Hydrangeas (Hydrangea petiolaris) are examples.

However, occasionally these types of climber can cause damage to the building, and this kind of greening is best avoided if possible. It is much better to provide a green wall façade system that climbers can use as a scaffold to climb up – this means that the building gets all the benefits from being greened, but avoids any potential structural damage.

2. VINES - CLIMBING PLANTS

Vines have a very strong natural tendency to grow vertically. They twine around their supports by the circular movements of their stem tips. There are many different types of vines that can be used on a green façade using vertical supports, some examples are listed below;

In theory, vines only need vertical supports, however in the case of wisteria for example, with a little effort, vines can be trained along horizontal supports. The spacing needed between the vertical supports depends on the species.

For slow to moderate growing climbers the gap between the supports to ensure maximum coverage needs to be approximately 200-400mm. For very vigorous species the supports can be as much as 800mm apart.

3. LEAF-TWINING CLIMBERS and TENDRIL CLIMBERS

Leaf- twining climbers depend on their leaf stems to hold on. These tend to be mainly deciduous. During the winter the dead leaf stems continue to hold onto the support even though the stems are more brittle. Much of the weight is taken by the plants stems being intertwined around the supports.

The most popular leaf-twining climbers are Clematis and Nasturtiums (Tropaeolum).

Examples of these climbers are;

A combination of horizontal and vertical elements offer the best kind of support for both of these types of climbers.

The size of the lattice depends on the vigor of the plants chosen. Slow to moderate climbers for example clematis, would need a smaller grid size than a vigorous climbing species such as grape vine.

4. RAMBLERS AND SCRAMBLING PLANTS

These types of plants use thorns, bristles and prickles in order to climb their way up a support. Their means of growing does not make them ideal candidates for upward growth, instead they lend themselves perfectly to be trained in a largely horizontal manner. This makes them ideal for large stretches of horizontal growth with a small vertical range.

The ideal support is composed purely of horizontal supports, the optimum vertical distance between the supports is approx. 400mm.

Other Considerations

Our green wall systems can be designed to incorporate a variety of climbers with different climbing mechanisms. We can also help to design a façade to fit almost any space, using a combination of horizontal, vertical and trellis façade.

The design of your green façade can also incorporate edible plants, for example tomatoes, runner beans, cucumbers, melons, courgettes, peas and passion-fruit can all be successfully grown amongst more permanent plants. This provides you with year long interest and also the potential of a tasty harvest!

Our vertical garden systems can also be adapted to be used as a method of creating an espalier or pleaching.

GREEN WALL TRELLIS LEAFLET download here

Get information about our NEW Green Wall trellis system.