Green roof Construction

A green roof offers many advantages. Such a roof insulates well, counteracts the warming of the immediate environment, ensures a gradual drainage of water and purifies the air. Think carefully about the difference between an extensive green roof and an intensive green roof. An extensive green roof consists of fat plants, mosses or herbs that require little water and maintenance. An intensive green roof is a complete garden on your roof with grasses, shrubs and possibly even trees. Such a roof garden costs at least as much maintenance as your 'normal' garden around your house.

Constructing a green roof

With an extensive green roof of sedum (succulents) you contribute to the greening and sustainability of your living environment, but you also make it easy for yourself. When you purchase the sedum in the form of mats or cassettes, you can green your existing grey roof in a relatively short period of time. After this, you will receive tips and points of attention for laying your own green roof. To be sure of a solid and durable result, it is best to have your green roof installed by an expert green company. Such as Sedumroofshop, which specializes in the construction of sedum roofs.

Step 1: Assess whether your roof is suitable for a sedum roof

At 40 to 60 kilograms per square meter, a sedum roof is relatively light. With the advantage that your existing roof construction usually does not need to be adapted to carry the sedum. You can install a sedum roof on top of the concrete or bitumen of your current grey roof. To prevent the mats or cassettes with sedum from slipping off your roof, your roof must not be slanted more than 45 degrees. A tile roof is not suitable as a substrate for a sedum roof. Plastics cannot support the extra weight of a green roof. Roof tiles do not form a flat and stable substrate for sedum mats or sedum cassettes. However, you can replace the roof tiles with a different roof covering and then install a green roof on the new substrate.

Step 2: Check whether you need a permit for your green roof

Does the green roof you want to install weigh more than two hundred kilos per square meter or is the substrate layer (nutrient layer) thicker than twenty centimeters? If so, you will need a building permit for its construction. Most green roofs are so light and thin that you do not need to apply for a building permit. When estimating the weight, make sure that you assume a green roof that is saturated with water.

Step 3: choose your sedum plants

There are many types of sedum plants with which you can create a beautiful flowering sedum roof. Of the two hundred and fifty types of sedum plants, at least fifty are suitable for this purpose. Vegetable roofs usually incorporate the following six types of sedum plants in a sedum mat:

• Sedum acre
• Sedum album Coral Carpet
• Sedum hispanic
• Sedum lydium
• Sedum oreganum
• Sedum sexangulare.

Because each species flowers in a different period (of about five weeks), with the right combination of species you can make a sedum roof that flowers from April to September.

Step 4: Purchase all supplies

A green roof always consists of the following layers:

• protective film (protective fleece)
• drainage layer (drainage mat)
• substrate layer (roof garden soil)
• vegetation layer (e.g. sedum mats or sedum cassettes).

Between brackets are the materials you need for each layer. The substrate layer should be four centimeters thick when you apply sedum mats and six centimeters thick when you apply loose plants.

Step 5: Lay your green roof

As soon as you have all the necessities ready, you can start me laying your green roof. Please apply the following step-by-step plan.

1. Clean your existing roof thoroughly.
2. Apply a ball-wire grid to the hole of the rain pipe.
3. Place coarse gravel in a strip around this grid so that the substrate cannot wash into it.
4. Roll out the protective foil on the roof and cut this foil with scissors if necessary.
5. Roll out drainage roller, cut to size with scissors.
6. Roll out the filter fleece, but cut it with scissors.
7. Spread the substrate as evenly as possible over the roof. Do not use (sharp) tools to prevent damage to the roof.
8. Plant your plants in the substrate or roll out a vegetation blanket over the substrate.
9. Sprinkle the substrate lightly with water so that it can store moisture.

Would you like to know more about the possibilities of a sedum roof on your house? Please contact Groendaktotaal for a no-obligation consultation. We would like to get to know you!