Case Study: How the StormCap System is rehabilitating an ailing green roof pioneer and improving functionality for years to come.

The StormCap System is enhanced by Urbanscape for superior stormwater management and plant health.

By Rodney Chaney

The Severn Bank green roof  in Annapolis Maryland (MD) was ahead of its time.  Like many building owners who needed an onsite stormwater solution, this green roof was intended to be a workhorse. With historic rainfall in recent years, it was starting to burn out in sections.  Stormwater Capture Co was invited to inspect the problem and offer a solution to improve its functionality and restore its beauty. Below is the full story about this traditional green roof, now transformed with the StormCap system enhanced by Urbanscape.

Black stallion profile standing outdoors on a cloudy and stormy day.

Green Roof Pioneer: The beginning

The 13,000 square foot Severn green roof sits atop of a four story parking garage connected to a five story office building.  Its primary purpose was to address stormwater management needs near the historic downtown area of Annapolis – likely one of the first in Maryland built for the purpose of managing contributing stormwater.  Tecta America a pioneer in North American green roofs was consulted and contracted to install the roofing and green roof.   Tecta America has diligently maintained the roof since.

Stormwater Workshorse

For years, the green roof had functioned as designed. This workshorse managed well over seven million gallons of stormwater and maintained a healthy plant palette that the owners in the adjacent offices would look upon with pride.  The amenity space within the green roof area has provided a place to enjoy lunch or take a call alfresco.

Fast Forward A Decade Later: “Houston, we have a problem”

The Severn green roof had been designed to accept the contributing runoff from nearly half of the adjacent 20,000 square foot building roof managing the anticipated rain event. It retained both precipitation and runoff.  This workhorse managed twice the amount of water that fell directly on it. It was a great setup and worked beautifully for over a decade. Then, something happened…

Dealing with Historic Rain Events

Two exceptionally wet summers appeared to have caused the green roof to die in several significant areas. This was confusing as two wet summers should not have been enough to make the roof fail. After all, it had been designed to withstand a good bit of runoff.

In the last several years the region has seen historic rain events.  Many site stormwater management systems and municipal storm sewers have

Although many areas of the green roof were lush with excellent coverage other areas had almost completely burned out and in need of rehabilitation.

been overtaxed.

What went wrong and how to fix it?

As symptoms became apparent the owner and Tecta America were quick to act.  Stormwater Capture Co was asked to provide 3rd party consultation.  At the initial inspection, we were surprised to discover that although many areas of the green roof were lush with excellent coverage other areas had almost completely burned out.  What had gone wrong and how could we fix it? Upon closer inspection, we found several contributing factors.

Green roof with wet feet

The overflows designed to manage the onslaught of heavy flow from the contributing roof area hadn’t provided the fail-stop to keep the roof from “bogging out” for extended periods.   Even with a record of 7”+ rain events there was no evidence that the excess flow was reaching the height of the collar to allow for bypass.  Compounding the problem, the drainage assembly at sumps had been built at a time when drain perimeters weren’t typically installed.  In addition, the biomass of over a decade had accumulated to a point where the additional mechanism of evaporation was slow to dry.  While biomass is good, with these other factors this green roof was left with prolonged periods of “wet feet”.

If the green roof needed to manage only the water falling on it, this system would likely have continued to thrive.  However with this pioneer in contributing drainage, it was necessary to move the stormwater throughout the system more efficiently.

StormCap improves roof functionality and restores beauty

To remedy the problem, six hundred linear feet of perforated drain tile was trenched throughout. The indirect pattern allow for improved movement of water to all areas of the green roof.  Then eight expanded drain sumps were opened and framed with new SCC .063 perforated metal edge, SCC drain board, and ballast. Following this, the overflow on the “high side” of the green roof was adjusted by lowering the bypass collar height.  It was factored that 99% of rain events will be treated by the green roof.  So, even in heavy rain events the overflow won’t be tripped too often.

Upon our inspection, we found that only 3,000 square feet out of the total green roof footprint needed replacement.  This was the center of the green roof that received  the majority of contributing drainage.  We decided to solve this problem using several methods.

StormCap berm hosts deeper rooted natives and adaptives such as rudbeckia, asters, beards tongue, russian sage, lavender, phlox and babtisia.

Re-using Native Plants

After removing 3,000 square feet, we were able to reuse all of the nutrient rich biomass that had been built up over the past 12 years to build semi-intensive berms to harbor some deeper rooted natives and adaptives such as rudbeckia, asters, beards tongue, russian sage, lavender, phlox, babtisia, etc.

Not only did this reuse the existing material and help manage the excess of stormwater from the impervious deck area, it also created a great sightline from the amenity area that didn’t exist before.

StormCap Pre Vegetated Roof SystemStormCap Solution

The removed area was replaced with a high efficiency StormCap 1+3 profile by Stormwater Capture Co. Our proven assembly, consisting of  UrbanScape’s® high-performance needled mineral hydro blanket topped by our pre-vegetated mat, provides a healthy and instantly green roof .  This innovative systems now provides the retention needed and stormwater flow necessary to avoid “the bog” that was causing parts to die out in recent years.

Green again! 

After a few days of prep and a Saturday installation, the result amazed the owners Monday morning when they arrived to work.  Their green roof was in fact GREEN again!  The instant coverage of the sedum mat and the addition of the semi-intensive berms surrounding the amenity space were striking.  Less noticeable but more important than the “instant” coverage was the fact that the green roof will now manage stormwater more effectively and be ready for the sunny days well as the storms ahead.

Proud Green Roof Owners

The functional upgrade, and the addition of new visual interest, gave the owners a greater appreciation of what a healthy green roof can provide environmentally and emotionally.  In this scenario, we were able to solve a problem, add functionality, as well as provide a great new aesthetic to this existing “workhorse” green roof.

Your Green Roof Specialist / Design Consultant / Maintenance Support

Stormwater Capture Co offers a single source solution for a complete green roof system package such as the StormCap system. We are a one-stop-shop. Supplier of vegetated mats, high performing base layers, pavers and accessories.  We customize the system to local requirements and provide warranty and support.

Contact us for more info or a free quote on your upcoming project.

 

16 Jul 2018
Living Roof - Camden

Johnson & Johnson World Headquarters, New Brunswick, NJ

Stormwater Capture Co is featured in WATERPROOF! a quarterly magazine that is a great information resource for all types of waterproofers, including residential and commercial waterproofers, foundation contractors, and thousands of large roofing contractors.  The magazine reaches 10,000s interested readers throughout the U.S. every quarter.  Download the article: Waterproofing-Green-Roofs, Waterproof Mag, Summer 2018

 

About Stormwater Capture Co

Our team prides itself in being a hassle-free, one-stop-shop supplying vegetated systems that can be customized to local requirements, with warranty and maintenance support. We also offer ​access to a variety of analytical support service​s such as ​stormwater calculations specific to location ​and building/roof type.

We specialize in supplying green roof systems with​ high water retention-to weight ratio such as the StormCap system. Our premium base layers ​include​ the ​Needled ​M​ineral ​H​ydro ​B​lanket and can be easily cut to fit any shape and design.​ Contact us 855-786-7626 or send drawings to info@stormwatercaptureco.com get an estimate for your project.

 

Copyright © 2018 Stormwater Capture Co. LLC. All rights reserved.

 

 

Dedicated to sustainability, NYC Convention Center embodies world-class technological innovation

NYC Convention Center green roof brings nature back to urban core.

The 6.75-acre green roof on the Javits Convention Center makes the 27-year-old building an example of sustainable retrofitting – attracting many species of birds, bats, bees and even tourists who go on rooftop tours.  This NYC landmark is also closely monitored by a team of engineers from Drexel University and The Cooper Union for the Advancement of Science and Art who have designed and installed sensor systems to track its environmental impact.

CEO very pleased with performance of vegetated roof

In a recent interview with NPR (see video below), Javits’ CEO Alan Steel explained the significant aesthetic, environmental and economic benefits of the green roof.

Honey harvested in Fall of 2017 from NYC’s rooftop.

“Besides the great reaction, there are practical benefits.  We have three hundred thousand bees, we’ve seen 25 different species of birds on the roof. We reduced the temperature out here by about six degrees Fahrenheit and we also save about seven million gallons of stormwater runoff that’s absorbed in the  soil and the plants.  We’ve been able to reduce our energy consumption by about twenty six percent and that translated for us last year (2016) into a saving of about three million dollars.”  Javits is now also selling honey harvested from the rooftop.

“The success of our sustainability program epitomizes our rebirth as an organization, and this first batch of honey illustrates how far we have come in our efforts to reduce energy, create a wildlife haven and improve the quality of life in our neighborhood,” said President and CEO Alan Steel.

Green roofs are a learning laboratory for Engineers

Professor Franco Montalto in the department of Civil, Architectural and Environmental Engineering at Drexel College is the lead researcher on the Javits green roof project. He says in recent years the City of New York has made major commitments to sustainability and green infrastructure.

“The Javits Center green roof exemplifies the kind of environmentally sensible urban redevelopment projects that the City wants to encourage. The retrofit building will reduce urban runoff, mitigate the urban heat island effect, and, potentially have a cooling effect on the streets and buildings that surround it. Our research will seek to quantify these benefits,” said Montalto.

Watch NPR feature on Javits

Montalto’s research team is currently also monitoring more than 15 other green infrastructure sites in New York, New Jersey, and Pennsylvania. Students from The Cooper Union will monitor the data and use it to learn about and model functional sustainable design projects.

“The Javits Center green roof project provides Cooper Union students with a significant learning opportunity to study sustainable design and use New York City as a learning laboratory,” said Dr. Joseph Cataldo, a professor in the Albert Nerken School of Engineering at The Cooper Union.  “Our students are presently developing a model to predict the thermal behavior of the green roof using climate and infrared data. This information will be helpful to better gauge hydrology and temperature variations of the green roof, which, subsequently, is an important part of determining and understanding temperature patterns in green roofs and New York City as a whole.”

“Water and energy are intimately linked through the process of evapotranspiration,” Montalto said. “Incident solar radiation changes liquid water, originally deposited on the roof by precipitation, into water vapor which then leaves the roof surface. The energy consumed by this process keeps the roof and building cooler than it otherwise would be, since without the green roof this energy would simply heat up the roof surface. At the same time, if the air in the vicinity of the air conditioner intake pipes is cooler, these units have to work less to cool the -already cooler- building.”

For more on the Drexel and Cooper Union green roof research, click here.

About Stormwater Capture Co – Supplier of High Performing Vegetated Roofs

Stormwater Capture Co supplies green roof systems with high water retention to weight ratio, ideal for retrofits and new builds.

Our team prides itself in being a hassle-free, one-stop-shop supplying vegetated systems that can be customized to local requirements, with warranty and maintenance support. We also offer ​access to a variety of analytical support service​s such as ​stormwater calculations specific to location ​and building/roof type.

Stormwater Capture Co supplies a range of systems from lightweight to biodiverse.  Premium base layers ​include​ the ​Needled ​M​ineral ​H​ydro ​B​lanket.  Sedum blanket and base layers can be easily cut to fit any shape and design.​

Contact us 855-786-7626 or send drawings to info@stormwatercaptureco.com get an estimate for your project.

Copyright © 2018 Stormwater Capture Co. LLC. All rights reserved.

05 Apr 2018

Case Study

Project Name……………………Johnson & Johnson World Head Quarters
Location…………………………..New Brunswick, NJ
Size…………………………………4641 ftover 7 atrium rooftops
Date Installed……………………December 15 & 16, 2017
System…………………………….StormCapTM
Construction Type…………….Steel
Designer………………………….Mark Yanchuk, J&J
Installer…………………………..Robert Ganter Contractors Inc
StormCap pre vegetated roof system

High performing StormCap system is wind tested and retains up to 2.6″ of rainfall for superior stormwater management.

State-of-the-art building technology reduces Johnson & Johnson HQ footprint

One of the main reasons the green roof was included in the design of the building was to reduce the stormwater runoff from the roof and protect local watersheds. The vegetated roof also helps increase the lifespan of the roofing membrane and keeps the building, and surrounding area, cooler on hot days.

Johnson & Johnson’s World HQ has seven vegetated roofs using the StormCapTM vegetated system and has been awarded the first LEED Existing Buildings Gold Certification in New Jersey. The high performing, low maintenance StormCapTM system was selected for its superior water retention-to-weight ratio. Innovative and easy to install, this system uses quality pre-grown mats, engineered growing medium and high performing base layers such as Urbanscape®’s Needled Mineral Hydro Blanket which has superior water retention characteristics holding 90% of its volume in water. The green roof has no permanent irrigation.

The sedum blanket is delivered with 85% foliar coverage and provides an instant green cover. It consists of 10-12 species of sedum specially selected for their heat/drought tolerance and year-round visual interests.  The sedum blanket helps reduce water

Additional benefits for the employees

Research shows there are additional benefits for the employees and company itself, as views of nature promotes positive levels of well-being among employees and keeps employee performance at optimal levels. Good for the building, good for the environment and good for the employees and community. Win-win-win.

About Stormwater Capture Co

Our team prides itself in being a hassle-free, one-stop-shop supplying vegetated systems that can be customized to local requirements, with warranty and maintenance support. We also offer ​access to a variety of analytical support service​s such as ​stormwater calculations specific to location ​and building/roof type.

We specialize in supplying green roof systems with​ high water retention-to weight ratio such as the StormCap system. Our premium base layers ​include​ the ​Needled ​M​ineral ​H​ydro ​B​lanket and can be easily cut to fit any shape and design.​

Contact us 855-786-7626 or send drawings to info@stormwatercaptureco.com get an estimate for your project.

30 Mar 2018

Case Study

Project Name……………………2nd District Police Station
Location…………………………..Bethesda, MD
Size…………………………………4125 ft
Date Installed………………….. November 30, 2017
System…………………………….StormCapTM
Construction Type…………….Steel
Designer………………………….Michael Baker International
Installer…………………………..Gordon Contractors

Bethesda Police Department meets LEED® Silver Requirements

One of the main reasons the green roof was included in the design of the building was to reduce the stormwater runoff from the roof and protect local watersheds. The vegetated roof also helps increase the lifespan of the roofing membrane and keeps the building, and surrounding area, cooler on hot days.

The new 2nd District Police Station in downtown Bethesda is a unique public/private state-of-the-art police station designed to meet LEED® Silver certification requirements. It includes community space as well as a separate, secure entrance for police officers. The installation of the StormCapTM vegetated system with 1,000 plant plugs helps StonebridgeCarras developers meet the Montgomery County, MD Green Building and Sustainability Standards and Energy Guidelines.

StormCap pre vegetated roof systemThe high performing, low maintenance, StormCapTM system was selected for its superior water retention-to-weight ratio and excellent stormwater retention capability. The sedum blanket is delivered with 85% foliar coverage and provides an instant green cover. It consists of 10-12 species of sedum selected for their heat/drought tolerance and year-round visual interests. The sedum blanket helps reduce water evaporation, soil erosion and weed growth.

The Needled Mineral Hydro Blanket by UrbanscapeTM acts as a water reservoir to support plant health, and offers reliable stormwater management over the lifespan of the vegetated roof. Capturing up to 2.6″ (1.6 gal/ft2) of rainfall on the rooftop helps prevent stormwater pollution and protect local watersheds. The green roof has no permanent irrigation.

About Stormwater Capture Co

Our team prides itself in being a hassle-free, one-stop-shop supplying vegetated systems that can be customized to local requirements, with warranty and maintenance support. We also offer ​access to a variety of analytical support service​s such as ​stormwater calculations specific to location ​and ​building/roof type. We specialize in supplying green roof systems with​ high water retention-to weight ratio such as the StormCap system. Our premium base layers ​include​ the ​Needled ​M​ineral ​H​ydro ​B​lanket and can be easily cut to fit any shape and design.​ Contact us 855-786-7626 or send drawings to info@stormwatercaptureco.com get an estimate for your project.

16 Aug 2017

Case Study

Project Name…………………..Mastery Cramer Hill Elementary School
Location…………………………..Camden, NJ
Size…………………………………3000 ft2
Date Installed…………………..2017
System…………………………….StormCapTM
Construction Type…………….Steel
Designer………………………….Blackney Hayes Architects

 

StormCap pre vegetated roof systemStudents and teachers of Mastery Cramer Hill Elementary have a pleasing view of vegetated rooftop that changes appearance with the seasons.

Workers unroll the sedum blanket onto the growing medium.

A team of workers from Ganter Contractors install the nearly 3000 square feet of vegetated roof in less than one day.

One of the main reasons the green roof was included in the design of the building was to reduce the stormwater runoff from the roof. The vegetated roof also helps increase the lifespan of the roofing membrane and keeps the building, and surrounding area, cooler on hot days.

Needled Mineral Hydro BlanketThis school’s vegetated system features the lightweight Needled Mineral Hydro Blanket which acts as a water reservoir to support plant health, and offers reliable stormwater management over the lifespan of the vegetated roof.

The sedum blanket is delivered with 85% foliar coverage and provides an instant green cover. It consists of 10-12 species of sedum specially selected for their heat/drought tolerance and year-round visual interests.  The sedum blanket helps reduce water evaporation, soil erosion and weed growth. The green roof has no permanent irrigation.

Research shows improved behavior and academic achievement in students who have a view of natural landscapes from their classroom.

About Stormwater Capture Co

Our team prides itself in being a hassle-free, one-stop-shop supplying vegetated systems that can be customized to local requirements, with warranty and maintenance support. We also offer ​access to a variety of analytical support service​s such as ​stormwater calculations specific to location ​and building/roof type.

We specialize in supplying green roof systems with​ high water retention-to weight ratio such as the StormCap system. Our premium base layers ​include​ the ​Needled ​M​ineral ​H​ydro ​B​lanket and can be easily cut to fit any shape and design.​

Contact us 855-786-7626 or send drawings to info@stormwatercaptureco.com get an estimate for your project.