Continuing with the green colonization in our buildings, we find more and more green facades throughout the current real estate park. It is curious how an element of horizontal planting has been adapted to become part of a facade typology that is booming at this time. Do you want to know more about green facades ?

Perhaps the most striking and illustrative example, due to its good execution and the large green canvas that it provides to the viewer, is the green façade found in the access plaza of the Caixa Forum building in Madrid . This 24-meter-high facade is made by the French botanist Patrick Blanc . With a total of about 15,000 plants and 250 varieties of these, occupying an area of ​​460 m2.

THE LAYING OF THE GREEN FACADES

It is important to understand how these facades are attached to the existing building . The most common is the execution of a substructure anchored to the original façade that is usually arranged as a grid where modules are inserted in which the elements that give an image to that characteristic green aesthetic are incorporated.

That is why the plant facades or facades green suit the type of enclosure that provides the building on which it is to be carried out, however not all plants can be found in a plant facade. This is basically due to two reasons: the substrate and the size of the cultivated vegetation .

A widely used plant can be moss or grass , especially when you want to create a contrast between the facade and the green color by forming shapes or squares. On the other hand, for complete plant facades, climbing plants with a high density of foliage are usually used, such as:

• Hedera helix  (common ivy)
• Solanum jasminoide  (false jasmine or solano)
• Wisteria sinensis  (wisteria)
• Parthenocissus tricuspidata ( vine or virgin vine )

In short, they are climbers that colonize large surfaces, they are well entangled with the facade and great contrasts are achieved with the building.

HOW DO PLANTS GROW ON GREEN FACADES?

The thickness of the substrate  makes the difference when it comes to arranging the plant species on the green facade. Normally there is a substructure anchored to the supporting façade where the plants are placed, either climbing or turfgrass or creeping herbaceous. The type of vegetation that we find on these facades may be extensive or semi-intensive (as in the case of green roofs) so a thickness of up to 15 or 30 cm, respectively, is more than enough. The Caixa Forum example mentioned has a substrate thickness of 1 meter due to the number of species of all kinds that are used in it. Surprise yourself with the image.  

The usual way for the substrate to support verticality is by covering it with a felt in which holes are made to place the vegetation.

Normally, vegetation that has adapted to growth on slopes is chosen, but if another type is preferred, what is done is to place it horizontally in the modules or turf that will form the green façade and once the plants are fixed to the ground, place them vertically. modules.

THE CHOICE OF PLANT SPECIES 

The native vegetation typical of each place is the most suitable to be placed on this type of façade, but going deeper into the type of vegetation, it is interesting to know the orientations of the facades on which the green façade is going to be executed since the conditions light and sun exposure is highly variable depending on their arrangement. To the west and south we will prefer a vegetation that tolerates high exposures to solar radiation, especially on summer afternoons. Unlike the facades facing north , where we would place a type of plant that does not require so much light for its growth and can withstand colder temperatures.

 LANDSCAPE AND ARCHITECTURAL DETAILS

Aesthetically and thermally, a good option is to place evergreen vegetation on the opaque parts of the original facade to maintain the green image throughout the seasons of the year, while openings such as windows, it would be recommended that the Non-deciduous vegetation because its leaves provide shade to the interior of the property in summer and the fall of these in winter allows the entry of sunlight. It all depends on how the structure of the plant façades is assembled, since if it goes by modules, it is even possible to make changes, as if it were a puzzle.

IMPROVE THERMAL INSULATION WITH PLANTS

Like any system that is made up of plant elements, thermal improvement is very remarkable. The filtered entry of light controls the light intensity of the interior of the building and, in addition, the placement of the vegetal modules on the aforementioned support substructure creates an air chamber between the vegetation and the original façade, causing greater thermal insulation. inland. All this with a much lower energy cost than with the traditional system.

 THE IRRIGATION SYSTEM, AN ESSENTIAL ELEMENT

The last point for understanding the green facades is their irrigation system . The most common option is the drip system whose origin is located in the highest part of the green wall and by gravity the irrigation spreads over the entire surface. However, day by day exudation or exudative irrigation is gaining prominence , of which we have already spoken in the odd post.

An important factor is also the reuse of water . In normal cultivation conditions, the water falls to deep layers and we will not know more about it (well, the aquifers …), but being a vertical cultivation things changes. As if it were a hydroponic crop , the water not used by the plants or absorbed by the substrate is collected in the channels at the bottom of the façade and can be reused, thus increasing its ecological gradient.

As you can see, there is a whole world that you have to know to get to execute this type of plant facades that we hope you have started to know through Gardenprue.