The blog data here is a continuation of my previous Green Roof blog. Feel free to refer back to the site to my new Green Roof blog because it does contain alot of information - and I will be posting the same info both here and on the Green Roof for Florida blog for some time.
We use succulents in most all of our green roofs. Succulents are an excellent green roof plant in many different ways. Succulents generally store water in their stems and leaves in significant quantities. Cacti leaves are practically non-existent and most photosynthetic functions in cacti occur in the stems. Succulents have stomata on all green surfaces but at much lower surface densities than most other plants.
Because succulents store water they can survive and in most cases still 'look good' after a significant drought. Another benefit to succulents is one of offering a deterrent to fire through their water filled leaves and stems.
Some other drought tolerant non-succulents such as the sages and grasses produce flammable volatile oils that can add fuel or accelerant to a fire.
Most succulents do not need fertilizer in quantities required by non-succulents. We have seen the base nitrogen content in rain provide sufficient nutrients for many green roof succulents.
Succulents also do well in well-drained soils that will wick and absorb a minimum amount of water.
Today engineered soils, such as the MetroVerde engineered soil blends have taken the place of most 'dirt' on the roof.
And finally, we are now prepared to say in our opinion, the green roof plants we propagate and raise like round rays and pots better than square ones.
After viewing first hand the growth qualities and characteristics of our green roof plants grown from seed in round and square containers, and cuttings in both, we believe the round container has less negative impact on root formation than the square shape.
Although there is not a huge significant difference, we've noticed a definite difference in size and in transplanting issues.
Unfortunately round pots are not as space efficient as square pots.
Has anyone out there seen studies conducted on the difference between square pots and round pots? I'd like to hear from them.
Happy green roofing!
Sunday, December 21, 2008
Tuesday, December 16, 2008
Irrigation for Green Roofs. Have you already made up your mind?
A great article on green roofing technical issues by Kelly Luckett appears on a recent Green Roof Website and I recommend the read - lots of good info.
You can find my comments to irrigation issues as follows: (Note - I am pretty much against irrigation on a roof - too much tort liability exposure in my opinion remember Byrne v. Boadle from 1L?)
Hello Kelly:
I read your article on irrigation with interest.
I'd love to talk with you about how you can design a green roof to survive without irrigation.
I understand you may consider it hard to do, but it is very possible.
As a plant biologist for many years and a Florida nursery owner with my wife we too have held a great interest in green roofs, and have trials that have been in the field for years.
Now Florida is different from anywhere in the nation. We have the four H's - heat, humidity, hard freezes and hurricanes. And also a bunch of attorneys who got rich off of mold litigation and are looking at any irrigated roof as a lawsuit, arguing the mold in the building did come from the irrigated roof...
Lawyers aside, we wanted to develop a roofing system that was cheap and lightweight and would meet product approval for Florida Building Code - stricter than IBC - and was evergreen, could be used on sloped roofs, treated stormwater and provided wildlife habitat.
We tried trays and tray systems and mat systems like XeroFlor - http://www.xeroflora.com/ and everything in-between
We consider our 10 years or so of seeing trials not work, our biggest successes.
Tray based systems will not survive long term in Florida. This is our opinion. We do not represent XeroFlor but we have found mat systems are best for Florida's unique climate.
Florida is quite possibly on the verge of removing ballast, be it LECA or Expanded Clay or gravel from approved roofing materials lists because of hurricane damage possibilities. Imagine a roof full of gravel or expanded clay and a hurricane - now imagine the pellets flinging towards fenestration like a shotgun blast in a 150 mph gust.
Florida typically requires all roofing material to be permanently attached to the roof (DCA Roofing TAC guidance)and typically considers a green roof to be part of the building envelop.
So back to the irrigation...You can do a green roof in Florida without added irrigation - I don't know about north of Atlanta - but here in Florida it is certainly possible.
We have roofs in place that have not had a drop of irrigation from day one. And they are doing very well.
Sure, you see signs of stress during 2 month droughts.
But they still look pretty good...
And you don't have to fool with a mechanical system that can fail - one that supplies pressurized water...
And they do fine without fertilizer, but they like fertilizer too...
We heard the same advice years ago. You have to fertilize and irrigate. But our roofs speak for themselves. No irrigation. No fertilizer. No maintenance.
I spent years watching plants grow in Florida roof gutters, and in the cracks of hot asphalt pavement in over 100 degree heat, with desiccating winds, and watched plants grow in cracks of retaining walls for overpasses, and did they ever continue to grow!
One of my favorite green roofs is located in the roof gutter of the gas station next to our local Blockbuster Movie shop. No one irrigates it. No one fertilizers it. It is there year in and year out.
Maybe green roofs can be designed, installed and survive without irrigation. We know they can here in Florida...even with our harsh sun, heat, winds and storms...
I smile every time I read of someone saying it can't be done...
You can find my comments to irrigation issues as follows: (Note - I am pretty much against irrigation on a roof - too much tort liability exposure in my opinion remember Byrne v. Boadle from 1L?)
Hello Kelly:
I read your article on irrigation with interest.
I'd love to talk with you about how you can design a green roof to survive without irrigation.
I understand you may consider it hard to do, but it is very possible.
As a plant biologist for many years and a Florida nursery owner with my wife we too have held a great interest in green roofs, and have trials that have been in the field for years.
Now Florida is different from anywhere in the nation. We have the four H's - heat, humidity, hard freezes and hurricanes. And also a bunch of attorneys who got rich off of mold litigation and are looking at any irrigated roof as a lawsuit, arguing the mold in the building did come from the irrigated roof...
Lawyers aside, we wanted to develop a roofing system that was cheap and lightweight and would meet product approval for Florida Building Code - stricter than IBC - and was evergreen, could be used on sloped roofs, treated stormwater and provided wildlife habitat.
We tried trays and tray systems and mat systems like XeroFlor - http://www.xeroflora.com/ and everything in-between
We consider our 10 years or so of seeing trials not work, our biggest successes.
Tray based systems will not survive long term in Florida. This is our opinion. We do not represent XeroFlor but we have found mat systems are best for Florida's unique climate.
Florida is quite possibly on the verge of removing ballast, be it LECA or Expanded Clay or gravel from approved roofing materials lists because of hurricane damage possibilities. Imagine a roof full of gravel or expanded clay and a hurricane - now imagine the pellets flinging towards fenestration like a shotgun blast in a 150 mph gust.
Florida typically requires all roofing material to be permanently attached to the roof (DCA Roofing TAC guidance)and typically considers a green roof to be part of the building envelop.
So back to the irrigation...You can do a green roof in Florida without added irrigation - I don't know about north of Atlanta - but here in Florida it is certainly possible.
We have roofs in place that have not had a drop of irrigation from day one. And they are doing very well.
Sure, you see signs of stress during 2 month droughts.
But they still look pretty good...
And you don't have to fool with a mechanical system that can fail - one that supplies pressurized water...
And they do fine without fertilizer, but they like fertilizer too...
We heard the same advice years ago. You have to fertilize and irrigate. But our roofs speak for themselves. No irrigation. No fertilizer. No maintenance.
I spent years watching plants grow in Florida roof gutters, and in the cracks of hot asphalt pavement in over 100 degree heat, with desiccating winds, and watched plants grow in cracks of retaining walls for overpasses, and did they ever continue to grow!
One of my favorite green roofs is located in the roof gutter of the gas station next to our local Blockbuster Movie shop. No one irrigates it. No one fertilizers it. It is there year in and year out.
Maybe green roofs can be designed, installed and survive without irrigation. We know they can here in Florida...even with our harsh sun, heat, winds and storms...
I smile every time I read of someone saying it can't be done...
Sunday, December 7, 2008
Green Roof Planting Media - Second and Third Generation Products
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
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
Sunday, November 30, 2008
Choosing Plants for Green Roofs - The Season for Sedums to Die in Florida
Tis the season for some sedums to go dormant in Florida....
We have had a month of drought. The days are becoming shorter and shorter. The winds are brisk and desiccating. Temperatures have ranged from 60 to 80 degrees F during the day and 30 to 60 degrees F at night.
We have had three light to medium frosts.
Too much for some of the sedums...
The alliums are turning brown on top too - the brown curly cues typical of drought.
The Florida climate is the biggest drawback to using sedums on Green Roofs - at least don't count on the succulents being your prime plant...
They usually come back out in the spring.
Happy green roofing!
Monday, November 24, 2008
Green Roofs use of Expanded Clay and Lightweight Expanded Clay Aggregate
The State of Florida has recently requested studies analyzing the use of gravel and aggregate on roofs and the potential of gravel ballast to break windows and other fenestration components of a building during hurricanes.
Preliminary research by the University of Florida shows that gravel ballast may be the cause of unnecessary glass failure and subsequent water damage.
Hurricane Alicia in 1983 devastated the Houston area, and much of the urban fenestration damage was attributed to gravel ballast ripped off the roofs by the hurricane force winds and shot across the city like pellets.
As Florida's green roofing industry develops, designers should be aware of the potential for tort damage liability once their specified product damages anothers property.
We should be careful about placing any gravel or pellet like material in a green roof until all the appropriate studies have been conducted to determine the level of safety for such product use.
Preliminary research by the University of Florida shows that gravel ballast may be the cause of unnecessary glass failure and subsequent water damage.
Hurricane Alicia in 1983 devastated the Houston area, and much of the urban fenestration damage was attributed to gravel ballast ripped off the roofs by the hurricane force winds and shot across the city like pellets.
As Florida's green roofing industry develops, designers should be aware of the potential for tort damage liability once their specified product damages anothers property.
We should be careful about placing any gravel or pellet like material in a green roof until all the appropriate studies have been conducted to determine the level of safety for such product use.
Wednesday, November 19, 2008
Frost & The Florida Green Roof
Tonight is the second night of the November 2008 winter where the outside temperature is expected to drop below freezing. Last night there were low in the mid to low 20's all across North Florida and the same is expected tonight.
Expected seasonal weather like this creates a huge challenge for the vegetated roof designer in Florida. Not just cold weather alone - because many northern green roofs survive much colder temperatures.
No - it is the combination of two weeks ago we were experiencing heat and humidity at high levels and now the frost - little if any hardening off of the roof plants.
I pose a question here. What happens when many of the native plants here that are deciduous or produce leaf litter - what happens when leaf matter dies from frost or drought? One of the answers is that we see a marked increase in leaf litter buildup.
Leaf litter turns into fuel once ignited. Dead plant matter, dried by desiccating cold winds can easily and rapidly burn when exposed to a spark or heat source.
Fire occurs in nature to cleanse dead plant matter from the environment and return nutrients to the soil. The chance of a roof fire increase once flammable, dried leaf litter accumulates on a green roof.
ASTM has recognized this potential problem and is developing standards for green roof plants.
The good designer will also strive to incorporate plants that prevent or greatly reduce the chances of leaf litter build up.
As we enter the season where many plants are dropping their leaves and becoming dormant, we should ask ourselves as we design green roofs, about potential fire issues with the plants we are selecting.
Better safe than sorry.
Expected seasonal weather like this creates a huge challenge for the vegetated roof designer in Florida. Not just cold weather alone - because many northern green roofs survive much colder temperatures.
No - it is the combination of two weeks ago we were experiencing heat and humidity at high levels and now the frost - little if any hardening off of the roof plants.
I pose a question here. What happens when many of the native plants here that are deciduous or produce leaf litter - what happens when leaf matter dies from frost or drought? One of the answers is that we see a marked increase in leaf litter buildup.
Leaf litter turns into fuel once ignited. Dead plant matter, dried by desiccating cold winds can easily and rapidly burn when exposed to a spark or heat source.
Fire occurs in nature to cleanse dead plant matter from the environment and return nutrients to the soil. The chance of a roof fire increase once flammable, dried leaf litter accumulates on a green roof.
ASTM has recognized this potential problem and is developing standards for green roof plants.
The good designer will also strive to incorporate plants that prevent or greatly reduce the chances of leaf litter build up.
As we enter the season where many plants are dropping their leaves and becoming dormant, we should ask ourselves as we design green roofs, about potential fire issues with the plants we are selecting.
Better safe than sorry.
Monday, November 17, 2008
Green Roofs in Florida and the Southeastern US. Insulation values for real?
We can all assume that thick intensive green (vegetated roofs) provide a measure of insulation - but what about thinner, extensive green roofs? Do extensive green roofs, say 2 to 4 inches thick provide insulation benefits?
Jincy, Ruairi and I have tracked the insulating factors of several extensive roofs, comprised of the MetroVerde mat roof system during the 2008 summer season.
What we found was very interesting.
Using a Extech Infrared IRC40 thermal imaging unit we measured the temperature of the roof decking undersides for roofs with (A) extensive 3" thick mat based vegetated roofs planted with allium and iceplant, and (B) asphalt shingle covered decking.
Not surprisingly, the underneath of the roof decking on asphalt shingle roofs averaged 125 - 130 degrees F during July, August and September 2008.
Temperatures of the undersides of the roof decking below asphalt shingles covered with the MetroVerde extensive mat systems averaged 84 - 86 degrees F at the same time of day.
Moreover, it is expected that the green roof mat system will protect the asphalt shingles from solar degradation.
So do extensive green roofs insulate a roof from solar gain? The answer is an undeniable Yes!
Jincy, Ruairi and I have tracked the insulating factors of several extensive roofs, comprised of the MetroVerde mat roof system during the 2008 summer season.
What we found was very interesting.
Using a Extech Infrared IRC40 thermal imaging unit we measured the temperature of the roof decking undersides for roofs with (A) extensive 3" thick mat based vegetated roofs planted with allium and iceplant, and (B) asphalt shingle covered decking.
Not surprisingly, the underneath of the roof decking on asphalt shingle roofs averaged 125 - 130 degrees F during July, August and September 2008.
Temperatures of the undersides of the roof decking below asphalt shingles covered with the MetroVerde extensive mat systems averaged 84 - 86 degrees F at the same time of day.
Moreover, it is expected that the green roof mat system will protect the asphalt shingles from solar degradation.
So do extensive green roofs insulate a roof from solar gain? The answer is an undeniable Yes!
Green Roofs in Florida and Cooler Weather
It is becoming cooler and night now and well should be - it is almost Thanksgiving & most green roof plants on our projects are very happy that the long and tortuous ordeal with Florida's heat and humidity is almost over for a season...
Many of the plants bear battle scars from Tropical Storm Fay (way, way too much water) and the ever present afternoon humidity bath.
The Sempervivums are starting to revive...you can see new growth expanding out from the middle of the plant, the brown, wilted areas falling away from the perimeters.
This is the time of year for dormancy for some of the sedums - - they are turning brown and melting away while others are just melting after a long stressful battle with the Florida humidity.
Iceplant is doing well. Iceplant planted on the ground melted out during T.S. Fay but those clumps on the roofs actually thrived.
Interestingly, the allium likes the cold weather too - its leaf blades perk right up.
So now is a major time for seasonal change in North Florida for green roofs. Stay tuned for more updates!
Many of the plants bear battle scars from Tropical Storm Fay (way, way too much water) and the ever present afternoon humidity bath.
The Sempervivums are starting to revive...you can see new growth expanding out from the middle of the plant, the brown, wilted areas falling away from the perimeters.
This is the time of year for dormancy for some of the sedums - - they are turning brown and melting away while others are just melting after a long stressful battle with the Florida humidity.
Iceplant is doing well. Iceplant planted on the ground melted out during T.S. Fay but those clumps on the roofs actually thrived.
Interestingly, the allium likes the cold weather too - its leaf blades perk right up.
So now is a major time for seasonal change in North Florida for green roofs. Stay tuned for more updates!
Friday, November 14, 2008
Green Roofs in Florida -
Palms and/or other trees on roofs present many challenges to the designer. In Florida these issues can include: (1) weight, (2) wind speed uplift during tropical storms or hurricanes, (3) irrigation and maintenance requirements, (4) fire safety and more.
Though I focus on thin, lightweight Green Roof mats (much less expensive) there will be clients who would like to have a roof with trees. Certain challenges are presented to us in designing a roof capable of supporting trees. First and foremost your structural engineer has to provide a deck capable of handling the loading.
We will be collecting photos of Florida green roofs that include trees and large shrubs. Send your photo in to Kevin for posting - along with a description of the roof, location, how long the roof has been in existence and other data.
Holidays are coming up - what better way to celebrate than with a blooming green roof!
Cheers..
Monday, November 3, 2008
Green Roofs can be vertical green vines also - Choosing the right plant and planting system lays the foundation for success.
Try a MetroVerde Shade Trellis! Based on the concept that a deciduous vine will block solar gain during the summer when the leaves are growing and allowing needed heat during the winter months when the leaves are off - MetroVerde's shade trellis combines plant requirements with awning frame design to produce a product that 1. cleans stormwater, 2. provides habitat and 3. creates a beautiful sense of place!
Green Roofs - Another Volunteer Vegetated Florida Roof
Walking the streets of almost all cities and towns you can see plants growing in the toughest of places.
They grow in the cracks between the concrete in the middle of the busiest streets and interstates. They grow up walls, peaking from the tiniest of crevasses. The grow in gutters and in roof seams. Give a plant a chance and many species will grow just about anywhere there is a little sunlight and occasional water or moisture.
The philosophy we carried with us over the years of experimenting with how to successfully grow plants on roofs was simple. It was based on watching plants grow in the most inopportune places.
Our goal was to design a vegetated or green roof that inherently had the following characteristics: 1. Low weight, 2. Reasonable cost, 3. Leaves and color all year, 4. fire resistant, 6. heat, humidity and hurricane resistant, 7. Florida Department of Community Affairs approved, 8. treats stormwater, 9. provides habitat for wildlife, 10. was low maintenance, 11. could be used on slopes (we can go vertical), and finally - a roof that would last - season after season.
We believe we have developed what we set out to do!
Call Judy at MetroVerde - 904-294-2656 to find out more about your new green roof!
Sunday, November 2, 2008
Check out this Website - Living Houses! Living Group Designs and Plans Review by Karl Wilson
Wow! Karl Wilson revealed a set of Green Parking Garage plans and I met two green architects - Alain Dezii and John Szerdi this week. Their Architectural firm in Fort Worth is a living building - all the gray water is treated in modular interior wetlands and the only potable water is used in the faucets.
The open air plenum system keeps the 4 story building amazingly cool!
They even have roof gardens - with native grasses, palms and more!
Think of Alain and John when you need a green, living building design! Check out their website!
Think of Karl's solar panel shaded parking garage roof with living walls when you think institutional, medical or parking garages! Check out Karl's website!
The open air plenum system keeps the 4 story building amazingly cool!
They even have roof gardens - with native grasses, palms and more!
Think of Alain and John when you need a green, living building design! Check out their website!
Think of Karl's solar panel shaded parking garage roof with living walls when you think institutional, medical or parking garages! Check out Karl's website!
Monday, October 27, 2008
Florida Green Roof Project Continues!
The new Florida Green Roof continues to grow with more and more succulents, agaves and cacti daily!
Once the structural plantings are completed the oobleck will be added around the plants, allium seeds sown and then wait for the plants to take off and fill out the mats!
Contact Judy @ MetroVerde for your green roof!
Sunday, October 26, 2008
Green Roof Plants Bloomin! Florida Green Roof Project
October is a great time of the year for Green Roof Plants! Many of the species with flowers of a red hue are blooming! Email Judy for your personalized roof!
Friday, October 24, 2008
Sustainable Florida! Green Roofs! UCF Orlando October 21, 2008
I attended the Collin's Center Sustainable Florida Conference this week hosted by UCF. The event was eye-opening and inspiring. Our panel presented on the urgent need to restore vertical green to the Urban Core.
Benefits from vertical green in the Urban Core include; A. Stormwater cleansing, B. Creation of Wildlife Habitat, and C. Reconnection of humans to our connections with nature - A Sense of Place Reality in an otherwise electronic world.
Check out the Sustainable Florida Website!
Sunday, October 19, 2008
Save Energy - Make your tea outdoors - even on a cloudy day...
Simple way to save energy. Instead of boiling your tea water, place several tea bags in a glass jar and set out in the sun. Cover well. By the end of the day your tea is brewed!
Vertical Wall Hydroponics - grow your vegetables anywhere!
We are developing wall systems to grow vegetables, herbs and flowers on any wall with a hybrid hydroponic watering and nutrient system!
Hydrolettuce Part Two! Two Weeks old
It's been two weeks since we've planted the hydroponic lettuce and the plants have really grown! Stay tuned for more updates!
Update - Florida Green Roof Project - with installation of green roofing plants!
Plant installation on the New Florida Green Roof Project proceeding! Looks for more updates soon!
Thursday, October 16, 2008
Florida Green Roofing - what holds the plants to the mat during the initial installation? OOBLECK!
Least that is the nickname the agar based tackifier is called by the kids...very sticky to the touch...but it holds the expanded clay and other soil engineered materials together!
Use a concrete pump to move the slurry in large quantities. Hydroseeder outfits are not strong enough...
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