Typical roof garden sections

Below 2 typical roof garden sections. These are only to give an idea. Of course the designs change depending on the needs in the project.

The upper with conventional design. For drainage 2 nonwoven geotextile (filter fabric) layer and gravel in between were used on top of the waterproofing layer. (mineral drainage layer) Heavy and cost more to take the gravel to the roof. Bigger load on the concrete.

The below is with a geocomposite drainage layer, lightweight and easy to use. The drainage layer is only between 0.5- 1 kg depending on the material. ıt is factory made and tested material. The access water from the vegetation and soil comes to drainage layer and carried to channels.

How does erosion control mat function?

Geosynthetic erosion control mats help nature to establish a natural, vegetation cover, as it :

• acts as an artificial root-system
• holds soil particles and seeds
• reduces water and wind velocities
• creates a micro-climate and favours germination of seeds and growth
• reinforces the vegetation cover in the root-zone

Roof Gardens and Green roofs

Two systems - Two purposes

Roof gardens:

• To be used as a garden
• with rich vegetation on a thick layer of soil
• requires maintenance
  

Green Roofs:

• environment-friendly roof with a thin vegetal cover
• not to be used as garden
• low maintenance vegetation (mosses,
  sedums, herbs) on a thin layer of
  lightweight substrate

Geosynthetics erosion mats-Fields of applications

Fields of application of erosion control geosynthetic mats

• erosion prevention for embankments and slopes
• protection of riverbanks against erosion
• support of vegetation on steep slopes and geomembranes

Roof garden tips

Now it is spring and you may want to prepare a green roof. You know roof garden does not mean a garden on the roof only. It may be top of an underground garage or top of a underground structure.

An important thing is not to forget the drainage core of the drainage sheets or layers with a nonwoven (may be woven but non woven is cheaper) filter fabric.

The ready made drainage products already have filter on them. But you have to wrap filter on the drainage core. Otherwise the soil, gravel or etc may go inside the drainage layer and block the drainage or at least decrease the amount of water to be drained.

Drainage sheets are used to remove excess water.

On the drainage layers you may use a water retention layer depending on where you live.

For more information on green roof solutions check our roof garden section for all posts of this subject.

3D-Mat for erosion control

As seen on the picture above 3D mat is a three dimensional, structured, olive green (darker than the picture, you can see the speedlight lights) erosion control mat manufactured from polypropylene monofilaments.

It is easy the installation slopes upto 60 degrees. Covered with soil after seeding. Provides instant protection against soil erosion due to wind, rain, and flash flooding. Creates an artificial root system. Helps nature.

These type of erosion control products can be used for erosion protection of steep slopes, embankments, riverbanks, lakesides, shorelines, spillways, canals, and ditches. Also highly effective on golf courses and residential lawn areas.

decorative ponds

Decorative ponds for houses or even bigger ones like lakes are widely used by landscaping architects.

If you construct a pond on the side slopes you sometimes put some small sized gravel and some plants.

The plants and gravel or soil sometimes slide down to bottom of the pond.

3 dimensional geosynthetic mats for erosion control or 3D mat type green slope materials may help for this purpose.

On the membrane you can cover with a protection (nonwoven geotextile) and use mat.

These mats can also be used in fish ponds.
For the noise reduction property of the mats please check fountain section.

Roof garden system

In the design of roof gardens designers should choose the design system depending on the local weather and plant conditions. Because the climate and the plants are different in al the world. Especially the drainage layer is important for the plants.

Below another roof garden design is shown.

On the concrete substrate there is a waterproofing membrane and a root barrier on it. But in some designs it is possible to lay a nonwoven geotextile to protect the waterproofing layer and a protection concrete could be casted. So, the root barrier may not be used depending on the type of plants.

For the drain layer a geocomposite drainage layer can be used. Because it is made of light materials. Otherwise you should use gravel for drainage and it will cause a load of about 150 kg/m2 on the building. So, it is much better to use a composite drainage layer.

The drainage layer should have a good filter layer to prevent clogging.

On the drainage layer landscaping architects may use a water retention layer.

You can use a prevegetated mat and soil as growth medium on the top.

This system may be used as a good drainage system.

How can we control erosion?

In nature it often takes thousands of years till erosion has stopped and a gradual building up of a natural, vegetal cover has taken place.
Mankind can make artificial protection with concrete, stone, wood, etc. or help nature to establish a natural cover.

Also it is possible to use prefabricated plastic erosion control products. Three-dimensional erosion control mattings, made of polyamide monofilaments welded together where they cross, with an open space of over 95%.

long planters-drainage

If you have long planters, or some green areas in your balcony or terraces you may need a drainage layer in your planter to drain or to direct the water to drainage pipes. For this purposes you may use some prefabricated drains made of a drainage layer and filtre covered around it.

Even you may use the prefabricated vertical drains like colbonddrain horizontally.

Green slopes with wire mesh and Enkamat

Enkamat and wiremesh hold soil particals, stones and seeds. The Enkamat functions as a griplayer for hydroseeding.

First Enkamat is installed on the slope and then on it wiremesh.

As the green of the first hydroseeding does not cover the whole area, a second hydroseeding is needed.

Climbing plants have been planted in the toe of the slope. The last picture is taken one year after installation.

Especially near the roads you may have a green beautiful view.

Erosion control

Why erosion control

• during the erosion process soil particles are transported, resulting in the gradual deformation and destruction of slopes, banks, shores, rivers bottoms, etc.
• elsewhere, erosion causes undesirable sedimentation on agricultural land and roads, in rivers and drainage systems, etc.

How can we control erosion?

a)Existing slopes:

• prevent removal of the vegetation
• in case of new slopes protect the fertile surface layer by means of:
  -coarse, less erodible surface
  -flatter slopes / terraces
  -surface cover with concrete, stones, plastic sheets
  -temporary plastic sheets over surface in rain season
  -geosynthetic mats
  -biodegradable mats

b)In case of slopes of ditches/channels:

• revetment structure
• concrete blocks