Greenroofs have continued to gain support in the roofing community. They meet the goal for higher performance buildings. They provide a sustainability angle for large and small structures. They reduce stormwater runoff in hardscape environments. And, greenroofs provide visual aesthetics.
As an essentially vegetated landscape on a flat or sloped roof, greenroofs are sometimes dismissed as an option due potentially higher up-front investment. The long-term costs of a greenroof, however, are commonly lower. It mitigates the effects of storm water in several ways and provides a long life-span for the roof with negligible maintenance. A greenroof slows water flow, retaining up to 75% of the rainwater, which alleviates significant pressure on a stormwater infrastructures.
Geocells are helping the greenroof market continue to grow.
SLOPED GREENROOF EROSION CONTROL
Soil on a slope is at risk of erosion during storms, and when that slope is on a roof that erosion can be concerning. Geosynthetics provide stability for soils and security for vegetation in flat and sloped greenroof installations.
In Bangalore, India, StrataWeb® was utilized to provide a sloped greenroof design on a residential structure high performance and durability against adverse weather conditions while preserving a natural look.
GREENROOF PROJECT EXECUTION
While conventional gardens on a rooftop usually consist of a few pots and planters, a green roof system can cover the whole roof area with the cultivation of plant life without soil erosion. If the whole area was landscaped, it typically would be completed with vegetated soil, which could lead to heavy erosion and a lot of maintenance.
For the client in Bangalore, Strata Geosystems’ civil engineering technical team designed a StrataWeb® solution. The cost-effective, long-term design approach provided an HDPE geocell confinement system that prevented soil from slipping off the roof.
The process was simple: The StrataWeb® panels were placed across the roof, infilled with either soil or mulch, compacted using minimal equipment, and vegetated.
The securely anchored system supported the mulch and soil effectively to prevent erosion and reduce maintenance. The engineered perforations in the cell walls allowed for drainage for when the stormwater volume exceeded the uptake rate from the plants and the soil’s ability to retain more moisture.
The engineered system added significant value:
- Increased roof life span with significantly lower maintenance
- Sloped greenroof installation was completed within a week
- Very environmentally friendly
- Strong insulation characteristics for the home
- Exceptional aesthetics
Learn more about Strata Geosystems geosynthetics and engineering at www.strataindia.com.