1200 Building Ecoroof 1200 SW 12th 

Portland Oregon   Project Objective  The objective of the 1200 Building Ecoroof Grant Application was to supply a “least cost” solution on an urban high rise structure, but as the project developed we realized that there is an opportunity for another channel of communication. Currently, many Ecoroof solutions are focused on esthetics and liability rather than accomplishing their objective for least cost. The result in the market place is that General Contractors are out of touch with affordable solutions and they are reluctant to be held responsible for Ecoroof construction without expensive and unnecessary design elements, some of which I do not feel are appropriate for our local climate. Building Owners, Architects and General Contractors still are looking to nationally marketed Ecoroof systems because they include extensive warranties. Therefore, our goal was to install an Ecoroof on a high rise building in the urban core that was so cost effective that building owners would consider Ecoroofs as a viable option when re‐roofing their buildings. We also wanted to supply an Ecoroof that provided enough warranty that liability concern would not a hindrance, and one that had minimal maintenance/operational costs.  We wanted to develop a solution that would: 

Provided protection over the roofing membrane from Uv and maintenance activity, extending the life expectance of the roof membrane. 

Provide storm water detention which would allow the building owner to receive Storm Water user fee discounts. 

Provided additional insulation. 

Reduce heat sinks in the urban core. 

Provide habitat. 

Assist in the promotion of Portland as a sustainable environment. 

Project Description Ecoroof size: 7,200 sq ft Project Type: Lightweight Ecoroof General Description: The 1200 Building is an existing 10 story affordable apartment project in the central downtown district of Portland. The building was constructed with concrete masonry units and corefloor in 1982. The building consists of a single story podium with 9 story tower that is set back 35 feet from the face of the podium. The project proposal is to install an Ecoroof on an existing 10 story urban building that does not require structural upgrading and is cost effective. In order to accomplish that goal the design was limited to 3.5 inches of Progro Max Light soil medium with potted sedums and sedum cuttings. Material will be craned upon the roof using #1,500 totes. After the soil material is spread, it will be wrapped with jute fabric to prevent wind scour and then planted. The irrigation system would be temporary and placed on top of the soil.

Existing Conditions Built-up roofing with cap sheet. Note existing whole house roof top fans. Fans were removed and curbs were extended to 1’ above structural slab. Heat recovery ventilator system was added on the roof. The recovery system will capture the heat (BTU’s) from the building exhaust and return the tempered air to the common areas. Existing parapet used a riglet to terminate the roofing membrane, and the remaining parapet was exposed. New design included a TPO membrane extending from under the parapet cap down to the roof deck. The membrane is a separate sheet from the roof deck, which would allow for replacement without modification of the Ecoroof.

Ecoroof Design

First we determine if the 1200 Building could add an Ecoroof without structural modifications that would make it cost prohibitive. If the additional load is less than 5% of building mass you are not required to analysis your buildings for seismic upgrading, and therefore only have to be concerned with the dead load capacity of the buildings structural system. Through structural calculations we determined that we had to limit the design of our saturated load of 16.75 pfs.

Roof Membrane. We selected a 15 year Firestone TPO roofing membrane, which includes overburden (Ecoroofs) in the warranty. The membrane also acts as a root barrier, eliminating the root barrier cost.

Leak Detection. For building owners and managers the number one concern regarding Ecoroofs is leaks. The general public still believes that Ecoroofs can cause leaks, and if a leak is discovered in an Ecoroof, finding the source is next to impossible. To combat the concern Architects and building owners lean toward cost punitive solutions that price Ecoroofs out of consideration. Multiple leak detection systems are now coming to market. These

systems can produce a positive and negative electronic charge over the roof, providing pin point breaks in the electronic field that can be detected using proprietary instruments. Current market price for the installation of these systems is $0.50 per square foot for installation, and over $3,500 per trip for detection. The available systems are patented pending, and therefore competitive costs for detection are not yet available in our market. Still for the initial cost of $0.50 per square foot it is substantially less costly than poured membrane systems, and it replaces a roof flood test. Upon completion of the installation test you have established a base condition in-time where the roof was established as leak-free. Thank you for your inquiry and for specifying the ILDNW Electronic Field Vector Mapping (EFVM) test on your recent project. EFVM testing is a quality control test designed to determine the water-tight integrity of membranes used for roofing and waterproofing. The system uses the natural attraction of negative and positive electrical charges to locate leaks, as well as minute flaws, in roofing and waterproofing systems. EFVM provides a snap-shot in time of the integrity of roofing or waterproofing membranes. The test is an empirical test; if there are breaches or leaks, the test will find them. The test can be used as you have, for quality control testing in new construction and it is just as often used for forensic testing. EFVM can find leaks in existing membranes, through many types of overburden and under many different conditions. I hope you never have to use the system on this project again, but take comfort in the fact that if your new roof system leaks, we should be able to find the source with great accuracy, thus minimizing one of the most expensive aspects of owning a building. Thank you, once again!

How EFVM® Works:

ILD®’s proprietary EFVM® test is a low-voltage method that creates an electrical potential difference between a non-conductive membrane surface and conductive structural deck or substrate, which is earthed or grounded.

A. Small electrical pulses are directed onto the membrane. The electricity is searching for a ground connection.

An electric field is created by applying water on the membrane surface and using the water as a conductive medium. A breach in the membrane creates a vector (ground fault connection), which can then be measured by a certified ILD® technician.

B. If the membrane is watertight, the electricity is isolated and does not find a ground connection.

The EFVM® technician reads the electric flow traveling across the membrane, mapping the “vectors” with pin point accuracy.

C. If the membrane is not watertight, the electricity makes a ground connection and is pulled toward positive poles.

Once EFVM® testing is complete, customers receive CAD drawings, picture documentation and a written report detailing the location and nature of all breaches and defects.

Soil Mixture.

Pro-Gro Max Lite Extensive Tested Weight Weight per cubic foot Water Retention weight per cubic foot Water Retention, Volume % Dry Weight 9.0 pounds per cubic foot. 0.0 pounds (dry) 0.0 % (dry) Field Moisture Capacity (FMC) 39.0 pounds per cubic foot. 30.0 pounds 47.6% Saturated Bulk Density (SBD) 50.7 pounds per cubic foot. 41.7 pounds 68% Conclusion – At Field Moisture Capacity, 4 inches of media will hold 10 pounds of water or 1.2 gallons. At Saturated Bulk Density, 4 inches of media will hold 13.9 pounds of water or 1.7 gallons. I hope this is helpful. Please call me if you have any questions. Thank you, Dave Andrews Pro-Gro Mixes Office 503 682-3500 Cell 503 320-0620

Moisture retention. Because we are using a thin soil base that is light weight and free draining we eliminated the drainage mat. The mat would actually dry-out the soil base to the harm of the planted material since it supplies air movement under the soil structure. Since the roof membrane warranty relies on some protection from the overburden (Ecoroof), we received approval from Firestone to replace the drainage mat with a moisture retention blanket.

Drainage channel and walking path To accommodate walking paths to the elevator penthouse, service to mechanical, and to provide a drainage path to the roof drains a 2” thick x 2’ wide path of 1 ½” minus round drainage rock was installed. Using the drainage rock instead of pavers for the walking paths will allow for the migration of planting into the rock base. The filter fabric was “tucked” under the soil for a distance of 1’ at the edge of the path to keep the soil from migrating into the rock base.

Wind Scour. The soil material is so light that it will move with the wind currents prevalent at the elevations roofs of urban buildings. The concern was resolved by wrapping the soil with jute fabric which will decompose after the sedums are established.

Irrigation. We originally considered using a domestic residential sprinkler that would be operated by building maintenance, but we had concerns regarding damage that would result from irrigation hose movement. We were also informed that the landscaping sub-contractor wouldn’t extend warranty over the planting material without an irrigation system. We eliminated drip irrigation since the MaxLite soil material is so free draining, the drip irrigation would not be able to supply adequate moisture to all of the plants. The final design is a surface mounted “disposable” system, that is intended to operate for the first 3~4 years depending on the condition of the planting. The final cost of the irrigation system increased by over 120% because the building has inadequate water pressure at the building roof and the only available supply line size was ½” domestic. The resulting design used low pressure sprinkler heads and increased the number of irrigation zones from 2 to 7.

Costs 7,200 square feet @ $36,091.86 = $5.22 per square foot

1200 Building Summary Structural Engineering 1,200.00 Project Management 2,000.00 Permit 1,500.00

Leak Detection* 5,800.00 Soil (53 bags) 4,041.00 Trucking to site 1,200.00 Lift soil to roof 2,500.00 Landscaping 10,373.00 Irrigation** 4,988.00 Electrical for irrigation 375.00 Hose Bib 1,500.00 Contractor fee 1,846.62 PL & PD insurance 268.24

Total 37,591.86

*Leak Detection system was carried as a subcontract to the roofing sub-contractor which added mark-up twice. Total avoidable cost approximately $0.30 per square foot. **Water pressure at the top of the building was inadequate resulting in 7 additional zones to the irrigation system, along with low pressure sprinkler heads. Total avoidable costs approximately $0.33 per square foot. 7,200 square feet without extraneous costs = $4.59 per square foot

Challenges to Resolve

General Contractors are still inexperienced with the installation of Ecoroofs and are therefore reluctant to promote their installation.

o Lack of understanding leads to liability concerns. o GC’s are unable to accurately price, or capable of guiding the process to cost effective

solutions. o Lack of experience leads to coordination problems

Possible Solutions: Change marking of installation from the general public to commercial

roofers and Property Managers. Provide information to commercial roofers regarding available grants so

that they can coordinate Grant applications. (Currently Energy Trust of Oregon incentives are often coordinated by Electrical and Mechanical Contractors.)

Provide a standard design Ecoroof with qualified vendors and projected pricing that matched the available Grant per square foot cost.

Proper Ecoroof design o Too many General Contractor’s Ecoroof experience are those designed by Landscape

Architects that want them designed as Roof Gardens, adding soil depth, weight, structural requirements and complexity to the design. Possible Solution

Change the marketing strategy to from “Roof Garden” to cost basis. Re-roofing the 1200 building cost approximately $18.00 per square foot for 15~20 year expected life (removal, insulation, membrane and flashing). An additional $5.00 per square foot may result in doubling the roof life in today’s dollars……..or with a successful BES Grant, for $0.00 out of pocket.

Cost of leak detection system Possible Solution

Leak Detection was sub-contracted through the roofing contractor, adding addition O&P to the cost per square foot. Contract directly with vendor.

Current leak detection systems are not competitively priced. Negotiate a price per sq. ft. with selected vendors’ that would be included in the BES qualified vendor list.

Maintenance Program

Provide walk-thru to review and replace planting monthly until the fall of 2010 Turn on irrigation system July 15th Review irrigation coverage until September 15th 2010 Turn-off and drain irrigation system September 15th Provide one-year walk-thru and report to Bureau of Environmental Services. Log roof top activity

o Do not allow landscape maintenance with tools. o Log roof access for mechanical and elevator maintenance.

Conclusions By proving that you can install an Ecoroofs on a high rise building for approximately $5.00 per square foot, it allows BES the opportunity to consider changing its Gray to Green Initiative program to market driven approach. We can realistically accomplish the goal of 43 acres of Ecoroof coverage in the metropolitan area, by empowering the roofing and building management industry with an obtainable and affordable solution. Knowledgeable control over the product and process is essential in order to control costs. Perhaps if a standard system was developed, similar to the one used on the 1200 Building, BES could focus their energy and assets providing the product to the market place, rather than managing a Grant program. For instance:

If only one system was used, then determining if buildings were suitable for 16.75 pfs saturated weight would be a simpler study. Existing on-call Engineering services for structural analysis could be used for the program.

Using pre-qualified product and sub-contractors could result in lowered costs through a system approach.

Further cost reductions may be achieved by teaming with select roof membrane manufactures.

Special Thanks During this process the availability and spirited enthusiasm from the staff of Bureau of Environmental Services was contagious. Special thanks to; Tom Liptan Alice Meyers Amy Chomowicz They make working hard for a great result fun.