After literally thousands of soil mixture experiments we are making strong headway in developing the green roof soil medium that has the qualities we are looking for. As we look back over the years we can readily see how far we have come.
We've addressed the drainage and the flammability and the dust and the compactability and the water retention and the nutrients/organics issues.
Erosion was a huge issue that we wanted to resolve. Our focus was on lightweight, thin (low profile - primarily because of Florida's hurricane propensity), inexpensive vegetated roofs that would not only work on flat roofs AND we wanted our roofs to work on slopes - even severe slopes!
Today I installed a 20SF vegetated panel on a vertical wall at the house, less than ten minutes after the engineered soil and plants had been applied. Wow. We have come a long ways.
But we have a long ways to go.
Now that flexible vertical vegetated panels - less than 1" thick are a reality - now we are looking at technology that will allow us to apply vegetated panels directly overhead on ceilings. So here is the next challenge.
The era of filling planters or trays with dirt, loose soil mixtures, LECA or expanded clay and placing them on the roof is disappearing. Like the dinosaurs these applications will hang around for a while, with good usefullnes with large heftily
-engineered structures. LECA and Expanded Clay may soon be against building code in Florida for use on roofs - imagine a truck bed load of LECA pellets fling through the air in 150 MPH winds - something like a shotgun blast.
Toxicity free engineered planting media will be a requirement. LC 50 testing with minnows will become standard. Green building requirements will affect planting media design too.
The challenges are here - so are the opportunities...
Happy Green Roofing! Kevin