GREEN ROOF COMPONENTS
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PART 1 - GENERAL

1.1 SCOPE

Furnish all labor, materials, tools, and equipment to unload, hoist and install GreenGrid^® Green Roof System provided by Weston Solutions, Inc. (WESTON). GreenGrid^® modules shall include growth media and vegetation as specified on drawings or as directed by the Project Engineer. This work shall also include installation of edge treatments, rubber pavers, decorative ballast, slip-sheet, and an irrigation system, if specified.

1.2 RELATED WORK SPECIFIED ELSEWHERE

a. Roofing Systems

1.3 QUALITY ASSURANCE

a. There should be no deviation made from this specification or the detail drawings without prior written approval 14 days prior to the start of the project.

b. Before installation of the modules, the waterproofing surface shall be inspected by a technical representative of the waterproofing installer/manufacturer to determine the adequacy of the waterproofing surface to accept the modules.

c. It shall be the Owner’s responsibility to determine the adequacy of the structure to support the existing and proposed loads. Verification of the integrity of the waterproofing for water tightness shall also be the responsibility of the Owner if the green roof is installed on an existing waterproofing system.

d. Upon completion of the installation, an inspection shall be conducted by a GreenGrid^® Technical Representative to ascertain that the modules have been installed according to these specifications and details. This inspection is not intended to be a final inspection for the benefit of the owner but for the benefit of determining whether a warranty shall be issued.

e. The green roof modular components, growth media, vegetation, and other optional materials will be purchased from Weston Solutions, Inc., or through a licensed distributor.

1.4 SUBMITTALS

a. When the proposed project components vary outside of this specification, submit these altered components for review.

b. Submit an installation plan including but not limited to: waterproofing quality control, system delivery, and maintenance plan until green roof acceptance.

c. Provide a detailed water hook-up plan if an irrigation system is required on the drawings.

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PART 2 - GREENGRID^® MODULES

2.1 MODULES

a. GreenGrid^® Modules are formed of 150 mil (2.5-inch and 4-inch) and 200 mil (8-inch) recycled (100% post industrial) High Molecular Weight Polyethylene (HMWPE) protected with UV inhibitor and stabilizers.

b. GreenGrid^® Modules sizes (Module OD = ± ?”):

1. Ultra-Extensive:

a. 2’x2’x2.5”

2. Extensive:

a. 2’x2’x4”
b. 2’x4’x4”
c. 40”x40”x4”
d. 2’x2’ Triangle

3. Intensive:

a. 2’x2’x8”
b. 2’x4’x8”
c. 2’x2’ Triangle

c. GreenGrid^® Module to be delivered to the project location complete with growth media and pre-planted with vegetation of the color and type desired by the client suitable for a green roof application.

d. GreenGrid^® Module weights (maximum wet weight):

1. Ultra-Extensive System (2.5-inch): 11-13 lbs per sf wet

2. Extensive System (4-inch): 18-22 lbs per sf wet

3. Intensive System (8-inch): 35+ lbs per sf wet

e. GreenGrid^® Module clearance above the roof is 0.5 inches.

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2.2 GROWTH MEDIA

a. GreenGrid^® Growth Media is an engineered light weight blend consisting of inorganic and organic components. Formulations are based on the German FLL “Guidelines for Planning, Execution and Upkeep of Green-Roof Sites”

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2.3 VEGETATION

a. Extensive - GreenGrid^® recommended Extensive plant mixes are composed of highly drought resistant ground covers that can thrive in a non-irrigated (climate dependent), rooftop environment in the project location. Vegetation shall be selected according to their USDA hardiness zone classification.

i. Recommended planting density - Vegetation should be supplied in a minimum size of 2-inches deep by 1.5-inches wide (plugs) and planted 4 to 6 inches on center (18 to 16 plants per 2x4 module, respectively).

b. Intensive – GreenGrid^® recommended Intensive plant mixes shall include grasses, perennials, and/or groundcovers that can thrive in an irrigated or non-irrigated, rooftop environment in the project location. Plants shall be selected according to their USDA hardiness zone classification.

i. Typical planting density - Vegetation should be supplied in grow-plug or quart size containers and planted in the GreenGrid^® green roof modules at a rate of 8 to 12 inches on center (11 to 8 plants per 2x4 module, respectively).

c. Vegetation shall be installed in accordance with the landscape design

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2.4 GREENGRID^® ACCESORIES

2.4.1 Rubber Pavers (optional)

a. Standard Paver size: 2 feet by 2 feet, and 1.75-inches in depth. Various paver depths are available.

b. Pavers are composed of 100% recycled rubber and are available in various colors.

c. Standard Paver weight: 7.5 lbs. per square foot.

2.4.2 Edge Treatments (optional)

Standard: 0.040 Painted Aluminum (recycled content 91%) or 24 gauge Painted Steel (recycled content 28 to 35%) for placement on viewable edge of modules.

2.4.3 Irrigation Systems (optional)

Irrigation requirements will be dependent upon project location and plant selection. For Extensive GreenGrid^® Systems planted with a mix of highly drought resistant ground covers, an irrigation system is generally not needed (exceptions do apply to some arid climates). However, GreenGrid^® strongly recommends a backup system to irrigate the green roof during prolonged droughts or during hot dry windy weather patterns. Simple overhead spray system with spray heads, or spigot/hose/sprinkler systems are inexpensive and effective methods. These also provide the means to optimize the evaporative cooling effect of the GreenGrid^® Green Roof System during such weather events.

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PART 3 - EXECUTION

3.1 DELIVERY AND HANDLING

a. Installation Season:

1. Northern Climates: Unless otherwise permitted, module installation shall be done between April 15 and October 15, but not when the weather is below 50° F.

2. Southern Climates: Will be dependent upon weather and/or plant availability

b. Do not install on saturated roof surfaces or under freezing weather conditions, the latter unless with the express permission of Weston Solutions, Inc.

c. Coordinate the completion of installation within a 24-hour period from the time the modules are to be delivered.

d. Handle planted modules with care. Do not drop, kick, or point-load modules during handling and installation.

3.2 SITE PREPARATION

a. Perform module installation only after appropriate waterproofing system, with the proper taper to allow for drainage, has been installed and inspected. It is strongly recommended that these areas be flood tested prior to module installation to confirm water-tightness.

b. Erect safety signage and provide fall protection/fall prevention equipment as required under OSHA.

c. Restrict traffic from work areas until modules are installed and there after to restrict damage to the plant material.

d. Thoroughly sweep away all debris, foreign material, etc. from the waterproofing surface.

e. Refer to Waterproofing System manufactures’ recommendation toward acceptable slip-sheet protection fabric.

3.3 APPLICATION OF GREENGRID^® MODULES

a. Remove all debris from the slip-sheet surface that might interfere with installation of the modules or compromising the integrity of the waterproofing surface.

b. Place modules over the slip-sheet in the desired locations in accordance to the landscape design.

c. Modules shall be installed in straight rows, tight against each other, and arranged in the proper directional orientation.

d. Installed modules shall be watered sufficiently with a fine spray so as to thoroughly moisten the growth media from top to bottom. Water shall be free of substances harmful to plant growth. Hoses or other methods of temporary irrigation shall be furnished by the Contractor.

3.4 WARRANTY

a. GreenGrid^® Modules: WESTON warrants that each GreenGrid^® Module (the “Product”) will perform its function of containing plant growth media for a period of twenty (20) years from the date of shipment of the Product by Weston. As used herein, “Product” means only the module and excludes (i) any plants, growth media, and any other materials placed within the GreenGrid modules, or (ii) any irrigation, mechanical, structural, or electrical components contained therein or attached thereto.

b. Standard 30 Day Plant Limited Warranty: WESTON will supply replacement plant(s) free of charge for any plant found to be dead or in severe decline (beyond the point of returning to aesthetic and economic value) for a period of 30 Days from the date of shipment of the Product by Weston. This warranty only covers those species selected and/or approved selections by WESTON horticulturists. Those NOT approved but planted to meet a design requirement shall not be covered. This warranty is NOT in effect for plant material purchased and installed outside our recommended installation season (Installation Season: April 15th through October 15th) or plants purchased and installed by others.

c. OPTIONAL: 1 or 2 Year Extended Plant Limited Warranty. Please contact your local WESTON representative for details.

3.5 30-DAY MAINTENANCE PERIOD

a. Installation contractor shall maintain the GreenGrid® modules for a period of at least 30 days after completion prior to acceptance from building owner.

b. 30-Day maintenance shall include:

1. Water the GreenGrid^® System once a week (weather dependent) too aid in plant establishment. System shall be watered more frequently during extended hot and dry weather especially when plants are showing signs of wilting.

2. Perform spot weeding as necessary.

3. Repair, rework, and replant all areas that have washed out or are eroded. Replace undesirable or dead areas with new plants.

4. Apply suitable bio-controls, fungicides, or insecticides only as required to control diseases and insects. Comply with all applicable local, State and Federal regulations and label instructions when applying these materials.

c. Upon completion of the 30-day maintenance period, a written maintenance plan for the specific green roof system shall be submitted to the building owner. A GreenGrid^® Representative will be made available to go over this document.

3.6 ACCEPTANCE

a. Inspection to determine acceptance of modules will be made by the Owner, upon Contractor's request. Provide notification at least 7 working days before requested inspection date.

1. Modules will be acceptable, provided all requirements, including maintenance period, have been complied with, and healthy, even colored viable plants are established.

b. Upon acceptance, the Owner will assume module/plant maintenance.

3.7 CLEANING

a. Perform cleaning during installation of the work and upon completion of the work. Remove from site all excess materials, debris, and equipment.

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