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The purpose of this maintenance plan is to provide easy access to information required for monthly upkeep of a Rooftop Green modular vegetated roof system. The contents will help you and your facility carry out the necessary upkeep of irrigation, weeding unwanted species, identifying damage to trays, and information needed to monitor the growth of your desired species.Provided in the Appendix of this report is a description of each table, the definition of green roof specific terminology, and references for further information and questions.
Table 1. Table of Contents
Topic Page
1.0 Who performs my maintenance 2
2.0 Irrigation and winterization 3-4
3.0 Desired Species Identification List 5-9
4.0 Unwanted species and common weeds 10-12
5.0 General Roof and Drainage Maintenance 13
6.0 Monthly Maintenance Report 14
Appendix 1 15
Determining site specific information and challenges to maintenance before green roof installation- Roof type, manufacturer, installer -
Roof Condition-
Age of Roof membrane/materials-
Pre-existing condition-
Pre-existing condition-
Pre-existing condition-
MAINTENANCE MANUAL
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1.0 Who should be performing the maintenance on my Green Roof?
Rooftop Green is a modular green roof tray manufacturer and installer located in Cleveland Ohio. Except for contracted projects where maintenance is explicitly incorporated in the project scope and budget, Rooftop Green is never responsible for the ongoing upkeep of customer green roof sites. However, the Rooftop Green team will help you find the information and products you need for a long-lived and successful green roof.
Green roof maintenance is often times carried out by facility’s utility or maintenance team, landscaping crews, third party contractors, and sometimes committed individuals. It is strongly suggested that volunteers and individual maintenance personnel have hands-on experience with irrigation systems and a basic understanding of horticulture.
Most green roof systems require year-round care, with monitoring or maintenance occurring once a week to once every four months. The maintenance plan for a green roof is established to meet desired goals or objectives with the site. Goals often times reflect the use of the space or its designated purpose. If the green roof site is to host events and provide a manicured aesthetic, the maintenance of the green roof will likely occur often and be tailored to promote healthy colorful flowering season plants. If a green roof is meant to re-invigorate a natural portion of the environment, the green roof might never be weeded or maintained for species monocultures, allowing natural volunteers to take root over time. Take a minute to list your green roof goals and objectives
1.1 Possible Goals and Objectives of Green Roof Site
Goals and the Objectives Needed to Meet Those Goals
Goal Objective
Maintain the desired species selected for the roof Weed out competitors and volunteer species on a regular interval
Provide a habitat for pollinator species Use methods of maintenance and soil additives to promote healthy flowering of plants
Mimic the surrounding naturalized environment Allow volunteer species and naturalized plants to take root in sections of the roof
Use the roof as an educational tool Post signage and information that defines the green roof and the ecosystem services it provides
Reduce storm water and rainwater runoff Irrigate only as necessary to maintain healthy plant- life and allow for media to dry out before precipitation events.
List your Green Roof Goals and Objectives
Goals and the Objectives Needed to Meet Those Goals
Goal Objective
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2.0 Irrigation and Winterization
No green roof system can survive without water or precipitation events. To promote strong establishment of the species in your system, be sure to follow any provided watering schedules or watering regimens provided by your green roof manufacturer or maintenance contractor. Rooftop Green does not recommend following the advice of individuals or groups that are not in the profession of green roof or landscaping maintenance. Approved irrigation specialists could include, but are not limited to, Green Roof Professionals designated with GRP certification, green roof maintenance contractors, Rooftop Green specialists, and experiences green roof installers.
Table 2.0 Watering Schedule
Watering During Establishment Stage
This is the most crucial maintenance stage of Rooftop Green, LLC’s modular tray systems. Establishment for young species can be difficult in a rooftop environment. Appropriate watering techniques include overhead sprinkler systems connected to your standard pressure exterior spigot, overhead drip-tape irrigation, and many low pressure (20-90psi) handheld watering methods.
Week One (Days 1-7) – Tray needs to be in a nearly constant state of moisture. Daily watering for the first week immediately following the install of the Rooftop Green system is required for successful establishment. Be sure to wet the entire top of the trays and saturate at least the top two inches of media.
Week Two (Days 8-14) – Taper watering events to once every other day. Continue to saturate the first 1 to 2 inches of the tray. Continue to water daily on trays located on 20 degree slopes or steeper. Week Three (Days 15-21) – Water trays three times a week. Starting in the third week, trays should be completely saturated during watering events. For trays that have not started to show esablishment at this point, water more often (return to week 1’s water schedule).
Weeks Four through Eight – Watering events can be reduced to once every four days. Water as needed if high temperature or drought conditions occur. Continue to water trays that demonstrate small growth and less establishment more often.
Spot Irrigation – Watering should take place during drought and extreme heat conditions to maintain healthy vegetation with desirable performance and aesthetic characteristics. No green roof, no matter how old, is exempt from this general rule. -http://growrooftopgreen.com/wp-content/uploads/2016/04/WateringSchedule.pdf-
Spot irrigation is necessary for any dry season that is experiencing more than two weeks of 80-degree weather or hotter without precipitation events. Any weather condition in your area considered a drought or extreme heat event will also require the roof to be irrigated. Ideal irrigation times are just after dawn and mid-evening.
Rooftop Green strongly suggested the automation of any irrigation system on projects over 500 square feet. Hand- held watering solutions will likely be time consuming, and may be more prone to inconsistent coverage.
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Winterizing Your Irrigation:If your cold season experiences freezing events, be sure to disassemble or properly drain all irrigation components before the start of the season.
• Rain Barrels- Barrels should be drained and capped at any entrance points to keep water from entering the barrel, expanding when freezing, and cracking components. Spigots and overflow valves or passageways should remain open to allow any moisture trapped or leaking in to escape.
• Irrigation Timers- Electronic timers (including waterproof, and freeze proof times) should be taken down during the cold season and stores inside. Reducing the timer’s exposure to UV, expanding/contraction stress, and hot/cold condensation will increase its useful life and even accuracy.
• Irrigation and Drip-Tape Lines- Lines should be rolled up and stored out of ice and snow. Be sure to completely drain lines before removing from the roof, and make sure that all openings, valves, or pressure openings are open during storage.
• Sprinkler Heads and Caps- All sprinkler heads should be stored away from freezing moisture, ice, and snow.
Take note of any irrigation spacing and positioning before winter storage:
Irrigation Access-
Irrigation Lines-
Sprinkler Head Placement-
Sprinkler spacing-
Timer Placement and Settings-
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3.0 Desired Species Identification List
A mix of industry typical sedums mixed with flowering, colorful wildflower-aesthetic species.
Increased pollinator attraction and naturalized species use with a slight increase in weeding maintenance required.
sedum acre ‘Golden Carpet’
sedum acre ‘Oktoberfest’
sedum album
sedum ellacombianum sedum floriferum sedum forsterianum sedum glaucophyllum sedum hispanicum sedum hybridum sedum kamtschaticum sedum reflexum
sedum sediforme sedum selksianum sedum sexangulare
sedum spurium ‘Coccineum’
sedum spurium ‘Summer Glory’
sedum spurium ‘Voodoo”
sedum stoloniferum
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Table 4.0 Desired Species ReferenceSPECIES DESCRIPTION
Sedum Acre ‘Golden Carpet’
• Evergreen with golden leaves
• Tiny star-shaped flowers in midsummer
• May become invasive
• Full sun
• Yellow flower
• 1-3”
• Zone 4-9 Sedum Acre ‘Oktoberfest’
• Evergreen with green leaves
• Cream white/yellow star-shaped flowers
• Propagates very easily
• Full sun
• White/yellow flower
• 2-3”
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Zone 2-9 Sedum Album
• Bright green foliage
• Patches of flowers in late summer
• Very drought tolerant
• Full sun/partial shade
• White flower
• <6”
•
Zone 3-10 Sedum Ellacombianum
• Larger, vibrant green leaves
• Flowers in summer
• Distinctive seed heads in the fall
• Full sun
• Yellow flower
• 2-4”
• Zone 5-9 Sedum Floriferum ‘Weihenstephaner Gold’
• Fleshy foliage
• Low profile
• Full sun/partial shade
• Yellow flower
• 4”
• Zone 4-9
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SPECIES DESCRIPTION
Sedum Forsterianum ‘Silver Stone’
• Needle-like foliage
• Tight textured clusters
• Blooms in the summer
• Full sun
• Yellow flower
• 6-10”
• Zone 4-10 Sedum Glaucophyllum
• Light green, longer leaves
• Low profile
• Short sprays of flowers in early summer
• Partial shade
• White flower
• 2-4”
•
Zone 4-9 Sedum Hispanicum
• Shorter needle-like fleshy leaves
• Clusters of tiny flowers in summer
• Good companion with other sedum
• Full sun
• Light pink/white flower
• 2-3”
•
Zone 5-9 Sedum Hybridum ‘Czar’s Gold’
• Flatter, scalloped green leaves
• Red colored stems
• Flowers in late spring and later summer
• Full sun/partial shade
• Yellow flower
• 4-6”
• Zone 4-9 Sedum Kamtschticum
• Fleshy foliage
• Low profile
• Clusters of flowers in early summer
• Full sun/partial shade
• Yellow flower
• 6-9”
• Zone 3-8
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SPECIES DESCRIPTION
Sedum Reflexum ‘Blue Spruce’
• Blue leaves that resemble spruce needles
• Flower clusters appear in summer
• May become invasive
• Full sun/partial shade
• Yellow flower
• 6-9”
• Zone 3-8 Sedum Sediforme
• Turquoise colored rounder leaves
• Medium profile
• Flowers in spring
• Full sun/partial shade
• Creamy yellow flower
• 4-6”
•
Zone 5-10 Sedum Selksianum ‘Goldilocks’
• Narrow, hairy, dark-green leaves
• Taller stems
• Golden clusters of flowers in late summer
• Full sun
• Yellow, Gold flower
• 6-8”
•
Zone 4-9 Sedum Sexangulare
• Short, spiraling green leaves
• Flowers in early summer
• Bronzy-green color during winter
• Full sun/partial shade
• Yellow flower
• 3-4”
• Zone 2-9 Sedum Spurium ‘Coccineum’
• Red flat, fleshy leaves
• Thrives in drought-like edges
• Full sun
• Crimson flower
• 3-4”
• Zone 3-9
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SPECIES DESCRIPTION
Sedum Spurium ‘Summer Glory’
• Rounded green leaves
• Flowers in summer
• Shade tolerant
• Full sun/partial shade
• Deep pink, red flower
• 4-6”
• Zone 2-9 Sedum Spurium ‘Voodoo’
• Deep red, fleshy leaves
• Flowers in summer
• Drought tolerant
• Full sun/partial shade
• Deep pink flower
• 4-6”
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Zone 2-9 Sedum Stoloniferum
• Bright green short, flat leaves
• Flowers in summer
• Full sun/partial shade
• Pink flower
• 6-8”
•
Zone 7-9
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4.0 Unwanted Species and Common Weeds
The highest level of maintenance pertaining to weeding and watering takes place during the modular system’s establishment period. During this time, it is easiest for seeds from exterior sources, weeds, and volunteer species to take place in the exposed soil, before your desired species cover the space. Be sure to research the common tree species and weed species that are inclined to grow wild in your area. Above are image comparisons and the botanical names of each species we use in our mixes. This will allow you and your maintenance team to identify the desired species.
When weeding, be sure to push the scrim down against the media, pinch as close to the base of the plant as possible and remove as much of the weed structure as you can. For rooted tree saplings you may be required to cut a small portion of the green top netting on the tray. Be sure to use scissors or shears instead of a knife and always place it in a safe place that can keep it from coming in contact with your roof membrane.
Weeding is easiest to perform after a precipitation event or watering, but be cautious of your surroundings and any slippery surfaces on the roof top. Be sure that desired or vegetative growth is not establishing in vegetative free zones such as walkways, parapets, drainage openings or edgers.
Below is a small listing of weeds commonly found of rooftop projects across the U.S. Be sure to research site specific weeds and pests for your area before pulling. This List reflects common weeds and does not encompass the full variety of species and plant types that may take root in your system. If you are unsure that what you are pulling is a desired species, an acceptable volunteer, or a weed, feel free to contact a GRP or Rooftop Green Specialist.
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Table 3.0 Unwanted Species ReferenceCOMMON WEED SPECIES ON VEGETATED ROOFS
SPECIES DESCRIPTION
Moss (many variegated species)
• Dense mats of smaller individual plants
• Flowerless
• Typically grows in areas of dampness and shade
• Full sun/partial shade
• No red flower
• .1-3.9”
• Various zones Trifoliums (Clovers)
• Trifoliate leaves
• Flowers in early to late summer
• Spreads easily and rapidly
• Full sun
• White, red, purple, or yellow flower
• 6-12”
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Zone 3-8 Taraxacum Officinale (Dandelions)
• Longer, lobed leaves
• Flowers summer and spring
• Tap rooted, unforked hollow stems
• Full sun/partial shade
• White, yellow flower
• 4-8”
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Zone 3-9 Hypochoeris Radicata (False Dandelions)
• Longer, lobed leaves with fine hair
• Flowers summer and spring
• Solid, forked stems
• Full sun/partial shade
• 4-8”
• Zone 3-9
12 COMMON WEED SPECIES ON VEGETATED ROOFS
SPECIES DESCRIPTION
Alnus Rubra
• Broadleaf tree
• Ovate leaves with serrated edges
• Woody stem
• Full sun/partial shade
• 66-98’
Salix
• Willow tree
• Elongated and serrated leaves
• Very tough roots
• Full sun/partial shade
• 6-15’
• Zones 2-9
Other Species Commonly Found in Rooftop Projects:
• Capsella-bursa-pastoris
• Stelleria ssp
• Chamaesyce maculate
• Oxalis stricta
• Chives
• Portulaca oleracea Herbicides
Typically avoided in green roof maintenance, herbicides are hard to control and often times generate a
lot of accidental loss of vegetation. Herbicides are sometimes used as a cost savings strategy to the more
time consuming pulling of weeds by facility owners and maintenance groups. Herbicides are only cost
effective on certain systems and green roofs. Unnecessary use of herbicides should be avoided, and may
often times be an indicator that weeding events simply need to take place more often.
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5.0
General Roof and Drainage MaintenanceThe roof material and structure of the green roof site will at times also need maintenance. The appropriate individual should create a schedule to perform regular site visits to inspect the roofing materials and overall development of the project. This schedule should reflect the most effective interval for running maintenance on the green roof. Some factors that may control the interval length between visits include any required watering, how often the roof needs weeding, a schedule created by the installer for the project specifically, or seasonal changes.
Upon site visits all of the following steps should be taken to ensure the long success of the roof.
1. Inspection of the building for signs of damage or leaking, including splits blisters and peeling of the waterproofing membrane.
2. Clogged drainage channels or drainage caps, and filled or clogged down spouting.
3. Examine the seals on any detached roof equipment or new roof equipment.
4. Report on any structural weakness, movement in the roof, or separation of roof and parapet components
5. Check for missing mortar or decaying sealants and record all findings with images and a simple description.
The remaining steps are typically limited to the individuals conducting your green roof maintenance and not a roofing contractor.
6. Check trays for shifted or mounding media for re-distribution. Carefully remove any aggregate from waterproofing membrane
7. Take note and report on any bare spots for replanting or media amendments.
8. Remove any undesired species/weeds or dead plants to be replaced. Be sure to clean up all debris from weeding and any that may have fallen on the roof (i.e. leaves, branched, built up organic matter, trash, and any die-back that could attract nesting birds.
9. Clear all vegetation from non-vegetative sections of the roof like drainage areas, walkways and flashings.
10. Determine plant health for ongoing maintenance (are they dry, keeping their original color,
staying in the tray, competing with weeds, too many large bare spots, etc.).
14 MONTHLY MAINTENANCE REPORT
INSPECTOR
REPORT #: DATE: TIME:
INSPECTOR NAME(S):
LAST INSPECTION DATE: NEXT INSPECTION DATE:
CHECKLIST
Weed unwanted species ☐ YES ☐ NO
Burnout spots or discoloration ☐ YES ☐ NO
Damaged trays ☐ YES ☐ NO
Clear drains, spouting, drainage areas ☐ YES ☐ NO
Water access points turned on ☐ YES ☐ NO
Irrigation system power ☐ YES ☐ NO
Irrigation system leaks/o-rings ☐ YES ☐ NO
Irrigation adjustments ☐ YES ☐ NO
Tray saturation level 1 2 3 4 5
Previous Irrigation Schedule: Current Irrigation Schedule:
NOTES/DRAWINGS
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Appendix
Table 1.0: Table of contents and contents directory
Table 1.1: Possible goals and objectives section for your green roof project. Example goals provided. Review and provide maintenance group with your project goals prior to performing maintenance.
Table 2.0: Generic minimum watering scheduled required of modular green roof tray system germinating from seed. This schedule is for spring use and should be adapted for other seasons.
Table 3.0: Desired species identification table. When weeding, be sure to remind yourself of what the desired species look like and do not pull them.
Table 4.0: Common rooftop project weed species to the U.S. Check online for site-specific weeds and aggressive naturalized species to determine weeding interval.
Terminology in Order of Appearance
Media: An engineered combination of organic and inorganic matter that anchors vegetation on a roof, drains water from the roof, and sustains plant growth.
Soil: The unconsolidated mineral or organic material on the immediate surface of the earth that serves as a natural medium for growth of plants.
Volunteer: A volunteer is a plant that grows on its own, rather than being deliberately planted by a human. Unlike weeds, a volunteer may be encouraged once it appears, if deemed beneficial to the existing plant community.
Weed: Any unwanted plant. Weeds can be plants that were part of an original planting design that have migrated to different spots on the site. Weeds can be unwanted for various reasons: lack of visual appeal, invasiveness, harmful to roof components, etc.
Aggregate: Non-organic fragments that make up part of the growing medium, media.
Establishment Period: The establishment period is the amount of time it takes the plant material to reach 80%
coverage of the allotted green roof area. This may range anywhere from 0 days (pre-vegetated systems) to 5 years (systems that use a certain amount of seed or cuttings).
Flashing: The flashing system is used to seal the edges of a membranes at walls, expansion joints, drains, gravel stops, and other areas where the membrane is interrupted, penetrated, or terminated. Base or membrane base flashings cover the edges of the membrane. Cap flashing or counterflashing shields the upper edges of the membrane base flashing.
Module: A green roof system which combines one or more layers of the assembly into a single product (e.g.
drainage, growing media, plants).
*Definitions provided by Green Roofs for Healthy Cities: Advanced Green Roof Maintenance –Participant’s Manual. 20011)
