Greenfix extensive lightweight green roof for low roof load
With a Greenfix extensive lightweight green roof, you achieve a green roof solution for roofs with limited load-bearing capacity. You retain the benefits of an extensive system, but with an even lower load and faster installation.
This solution is ideal for renovations or light structures where traditional green roofs are not possible. You combine water retention, protection of the roof waterproofing, and aesthetics without structural interventions.
Technical advice for your green roof
Contact us for support with assembly, sizing, and choosing the right Greenfix system for your roof project.
Technical specifications
The lightweight system has been developed for maximum efficiency and minimal load:
- very low weight gain on the roof
- prefab or modular construction possible
- quick installation and limited processing time
- good water retention and drainage
- low maintenance
Characteristics of an extensive lightweight green roof
- water buffering volume: >50 l/m²
- saturated weight: <100 kg/m²
- total built-in height: ±10.5 cm
- roof pitch: 1 – 5°
Applications and integration
You mainly use lightweight green roofs on renovation roofs, steel structures, or buildings with limited load-bearing capacity. They offer a quick way to green existing roofs without a heavy build-up.
A slight slope is also recommended here. For a flat roof, use the Greenfix Retain buffer board (20 l/m²), optionally filled with 4/20 aggregate for walkable applications.
Structure of Greenfix extensive lightweight green roof
Greenfix sedum mat
A ready-made vegetation layer with coconut mats planted with at least 8 different species of sedum. The choice to instantly enjoy a green view. Thickness: 30 mm.
Greenfix extensive substrate mix
Green roof substrate. Mixture based on lava rock composed of organic and mineral components. Thickness: 60 mm.
Greenfix substrate board
A hydrophilic rockwool slab with a high water-holding capacity that serves as a substrate replacement. Height 25 mm.
Greenfix Retain
Perforated dimpled membrane acting as a drainage layer. Equipped with a filter geotextile on top, with an integrated water retention capacity of 6 l/m². Height: 20 mm.
Greenfix Protect
Protective layer made of recycled textile fibers to protect the roofing membrane against mechanical damage. Greenfix Protect also has a leveling function.
Greenfix root barrier film
Optional membrane to be installed if the roof waterproofing is not root-resistant.
FAQ
1. When do you choose a lightweight green roof?
For roofs with limited load-bearing capacity or in renovation projects.
2. How much does a lightweight system weigh?
This depends on the structure and saturation, but is significantly lower than classical systems.
Are his performances comparable to standard extensive?
Yes, but with a focus on weight loss.
4. Is roof preparation necessary?
Yes, checking the bearing capacity and waterproofing remains essential.
5. When do you use Greenfix Retain?
For flat roofs or increased water buffering.
