Saturday, December 19, 2009

Florida Green Roofs - Rainy December


Florida's weather has been at it again.  Drought and more drought then rain and more rain.  Very hot days then cold nights.  Smothering humidity then dry as dry can be.  Tough on the plants.   MetroVerde's MVGR3 system keeps the green roof plants irrigated but not too wet.  Designed for light weight, the engineered soil medium is typically no more than 2 inches thick.  Works well in Florida's harsh climatic conditions.  See www.metroverde.com or email judy@metroverde.com .

Thursday, December 17, 2009

Hurricanes, Wind Tunnel Testing, Florida Green Roofs and more


Extensive, non-irrigated green roofs for Florida and the southeastern US coastal areas.  Your MetroVerde Green Roof does not require irrigation, can survive long periods of drought, inundation, both freezing and sweltering temperatures while treating stormwater, providing wildlife habitat in the Urban Core and creating a beautiful Sense of Place.   Pictured above is the MV ER3 test panel at UF scheduled for wind testing in early 2010.  The test panel platform is adjustable from flat up to 45 degrees.  Because the system is a mat based structure - the roots are embedded into a monolithic, permanent platform - light weight - the MV ER3 weighs approximately 10 lbs per SF.

Saturday, December 5, 2009

Plants for Green Roofs in Florida

Bonsai style preparation for green roof plants in Florida is time consuming yet delivers results and is worth the time and effort. MetroVerde green roof plants are grown with no additional fertilizer and rely on native rainfall events for irrigation. The plugs shown above are one year old, having spent their life growing under conditions similar to what they will experience on the roof.

The plants shown here are Allium species - and we are experimenting with the native 'nodding onion' found growing across the southeastern United States.

I highly recommend anyone considering a vegetated green roof to plan well in advance and 'bonsai' the plants - acclimating them to the same harsh environment they will spend their life in on top of a roof.

Remember the 5 'H's of the Southeastern US and Florida - Hurricanes, High Humidity, Heat Extremes (Pressure cooker style), Hard Frosts , and High Winds that dry and dessicate plant leaves.

I wrote a blog entry last year about sprouting green roof plant seeds on the roof they will be planted upon - and though not always practical. In any event, growing the plants under non-fertilized, non-irrigated conditions until they are solidly established is a solid approach to plant success once on the roof.

I've seen too many vegetated roofs fail after the designer and installer use plants pumped full of fertilizer, not hardened off and used to significant amounts of irrigation. Once on a roof, the plants experience shock.

Natives are great - adapted native species excellent too.

Remember, prep your plants long before planting on the roof.

Kevin

Atlantis Living Walls - Living Walls for Florida, Vertical Green




Here is an interesting video of Atlantis Water Management System's Living Wall Concept. The design is solid, especially as the frame is made from 95% Post-Consumer recycled material - good LEED Compliant stats.

I'd make a few changes - such as setting the living wall frame off from the stucco wall by at least 4 - 6 inches and seal any penetrations for anchors with a good low VOC sealant.

Irrigation concept is good too, however I'd certainly capture the water as it exits the bottom of the system to prevent Slip and Fall litigation - you know how prone us American's are to lawsuits...look at the puddle at the end of the clip - Res Ipsa Loquitur.

The extra width will serve to provide stability - especially on free standing walls.

Any ideas how they could be used to treat stormwater?

Wednesday, December 2, 2009

Green Roofs for Florida - Irrigation required? No!


Now, many green roofs are not garden roofs. They are not full of lush, tropical vegetation with nitrogen fertilizers added and irrigated with water that should be charging our aquifers. The latest argument for irrigation of green roofs - is - it is OK if the irrigation water comes from recycled stormwater. Sounds good, right! But how many of proponents of rainwater recycling actually have had rainwater systems in place for some time? If they do they will tell you that the cisterns are empty most of the time! Yes, we have an annual rainfall amount of well over 50 inches per year, but we also have extended periods of time where there is little if any rainfall.

So the proponents of irrigated green roofs say - use city water backup!

I thought we were in water conservation mode here. Watering restrictions, etc...

Just don't irrigate your vegetated roof. Use native species! The other day on a conference call an engineer referred to the native species of plants as 'Weeds!"

It is all perspective. I like the thought of using native species, not irrigating and still having a great vegetated roof.

The above photo is a test panel at UF that has been sitting in a back lot with less than an inch of soil average for almost a year with no irrigation or fertilizer and is still functioning to drink and clean stormwater and provide habitat for pollinators, etc...

No, it is not Jungle Gardens. But it is a thriving, functioning Green Roof! Remember - there is a difference between Intensive Green Roofs that are irrigated, weight 10 times as much or more and cost ten times as much or more - and require massive structural support - and Extensive Green Roofs that are light weight, non-irrigated, non-fertilized and can be put on simple structures.