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Greenroofs & Walls of the World™ Virtual Summit 2011 Episode 12: Wind. Water. Heat. Grow. Greenroofs. Panel Presentation

on February 29, 2012 at 4:20 pm under

Today we have the pleasure to air the panel presentation “Wind. Water. Heat. Grow. Greenroofs.” from our inaugural  2011 Greenroofs & Walls of the World™ Virtual Summit with Dr. Bill Retzlaff, David Aponte, Kevin Songer, and Joe Webb  on and our  GreenroofsTV channel on YouTube.

A couple I’d known for years and the others were newer aquaintances, but  I was very excited to get these four professionals together – with their combined years of experience designing greenroofs in high-wind prone areas across the U.S., I knew we’d have a great discussion:

Aramis and I met Dr. Bill in 2006 at  Southern Illinois University Edwardsville  when I was invited to speak there through Kelly Luckett, AKA The Green Roof Guy – the president of Green Roof Blocks, a contributing editor of ours, and a good friend.  Kelly had been collaborating with Dr. Bill and his  G.R.E.E.N. program – a relationship of trialing  different aspects of greenroofing, including wind testing in June 2009, that has lasted for quite a few years now.  Although he hasn’t shared anything new in a few years,  Dr. Bill is also a contributing editor of; you can read about his work here.

I met architect Joe a few years ago at one of the Greening Rooftops for  Sustainable  Communities  Conferences when he talked about his emphasis on sustainability and presented on one of his greenroof projects,  Cheyenne I (251 Medical Center Blvd.).  In 2008 the building with its new greenroof came through Hurricane Ike, which  barreled  through Houston, unscathed.

We met fellow Latin, David, in Singapore in November, 2010 when we both spoke at the  International Skyrise Greenery Conference.  David talked about the similarities and differences between the climates of tropical Singapore and sub-tropical Puerto Rico.  Of course, his island is known for its prime location during hurricane season.

We still haven’t met Kevin in person (but hope to!), but were very impressed with his knowledge and experience with greenroofs in Jacksonville, Florida, having corresponded with him as well as read his blog posts and discussion board posts on native plants and wind trials.

This panel of experts say that greenroofs are impacted by wind, water and heat on an unrelenting basis.  Through wind trials and real hurricane survival stories in Houston, TX, Jacksonville, FL, Edwardsville, IL, and Puerto Rico, we have met those challenges and will discuss various projects’ responses and successes to Hurricanes Ike and (any others?). Drought, hot winds, and unseasonable 100 ° days can also quickly desiccate or kill greenroof plants.

Dr. Bill Retzlaff moderates discussing wind studies and plant trials for greenroofs at  Southern Illinois University Edwardsville.  Joe Webb talks about his project which endured 110 to 120 mph winds and 11″ of rain in 24 hours and shares water mapping and Living Building Challenge Water requirements.  Kevin Songer talks about the Outdoor Turbine Hurricane Simulator at the University of Florida, water conservation through ‘nature-based irrigation design,’ and the importance of biodiversity.  David Aponte speaks to his experience of engineering and designing greenroofs with the correct growing media and plants in hurricane-prone, sub-tropical Puerto Rico.

Bill Retzlaff, PhD, Co-Director of G.R.E.E.N., Chairman of the Research Committee of Green Roofs for Healthy Cities, Biological Sciences Professor and Associate Dean of the College of Arts and Sciences at Southern Illinois University Edwardsville (SIUE), has conducted wind tunnel testing of green roof systems and contributed research data for the new green roof wind uplift standard.  In addition, a 16,000 sf green roof on the SIUE campus has just experienced a wind “event” with no uplift or damage.  Dr. Bill is also a contributing editor on (2006); he is the G.R.E.E.N. Editor and talks about the various trials at the SIUE Green Roof Research Center.

David L Aponte, MSCE, GRP has a Master’s of Engineering in Water Resource Engineering and a Bachelor’s of Science degree in Environmental Engineering with several years experience in green roof design and the construction industry.  He is founder of PR Green Design, Inc. (PRGD) which is responsible for 80% of all the green roofs built in the island of Puerto Rico.  Projects range from small ecological roof to big scale intensive greening.   Since 1996, more than 150,000 sf of green roofs have been installed in Puerto Rico, but not all have survived the harsh environment of the tropics, especially in the extensive category.   As this new wave of green roof construction is reaching the Caribbean market many doubts and misconceptions have taken over local designers.   Should green roofs be designed here equally to those in northern climates?

Kevin Songer’s passion is restoring ‘volumetric green’ to the urban core, designing green roofs for MetroVerde.  MetroVerde’s green roof designs are structured for cyclone and hurricane impacted areas with native plants.  He holds a B.S. in Biology and a Juris Doctor in law (environmental and land use).  Kevin writes a daily green roof blog, Living Green Roofs.  He is a LEED BG+C and an ISA Certified Arborist & Municipal Specialist Arborist.  Follow @kevinsonger on twitter.

Joe Douglas Webb, AIA, is the principal of a small Houston based architecture and planning firm, Webb Architects, that specializes in commercial architecture, planning and city design projects.  Registered to practice architecture in 14 states, he is currently chair of Blueprint Houston, a past president of AIA Houston, a member of APA, USGBC, ULI and a NCARB Certificate holder.

After the presentation on the second day of the 2011 Greenroofs & Walls of the World™ Virtual Summit, Dr. Bill, David, Joe, and Kevin were available for a live Q & A session; the transcript was available archived for 30 days for participants of the Virtual Summit – unfortunately, we do not have it available now – one of the reasons to participate in this year’s Virtual Summit!

Note: Due to technical and other difficulties from the second party vendor who filmed our illustrious panel of four, this video did not have our standard 2011 Greenroofs & Walls of the World™ Virtual Summit branding initially, including the shots from Google Earth. We did, however, add it to the four affected panel presentations so that they would be effectively identified for posterity.

Enjoy!  Visit to see the Panel Session “Wind. Water. Heat. Grow. Greenroofs.” or click below:

Watch earlier videos on our exclusive Virtual Summit play list, or see the following Virtual Summit videos now available on our GreenroofsTV channel on YouTube:

Episode #11: “GreenRoofs in Australasia”  by  Matthew Dillon.
Episode #10: “The Vertical Garden – from Nature to Cities: An Interview with Patrick Blanc”  by  Patrick Blanc  and  me  with an introduction  by  Caroline Menetre.
Episode #9: “Sloped and Complex Green Roofs”  by  Richard Hayden.
Episode #8: “The Portland Ecoroof Program: A Cross-section of the Green Roof Movement in Portland, Oregon”  with  Tom Liptan,  Matt Burlin,  Amy Chomowicz,  Casey Cunningham, and  Alice Meyers.
Episode #7: “Constructing Gardens in the Sky”  by  Terry McGlade.
Episode# 6:  “Sky Meadows – Integrating People and Nature: Sustainable Green Roofs and Roof Gardens”  by  Dr. Nigel Dunnett.
Episode #5:  “Greenroofs & Walls for Educational & Social Equity in the Bronx”  Panel Session with  New York State Senator Gustavo Rivera,  Bronx Borough President Ruben Diaz Jr.,  Robert Bieder,  Jon Beuttler,  Jess Dannhauser,  Javier Lopez  and  Steve Ritz.
Episode #4:  Keynote Address “CSR, Corporate Social Responsibility – The Who, What, Where, When and How” by  Ralph Velasquez.
Episode #3:  “CDA Leads the Way for Incorporating Green Roof Space in an Airport Environment”  by  Rosemarie Andolino.
Episode #2:  “2011 Top 10 List of Hot Trends in Greenroof & Greenwall Design”  by  Haven Kiers  and  me.
Episode #1:  Opening Keynote Address “A New Place”  by  Charlie Miller.
VS2011 Opening Address  by Linda Velazquez (me!).

If you’re looking for an overview, make sure to see our  2011 Virtual Summit Highlights video (6:18) and our  2011 Virtual Summit Trailer (2:59).

Check back next week on GreenroofsTV for our 13th installment from the Greenroofs & Walls of the World™ Virtual Summit 2011!

~ Linda V.