1. Garden Roof Systems

2. This is an AIA accredited continuing education presentation offering one (1) HSW CEU for participating AIA members. Health, Safety & Welfare Credit

3. Accreditation Statement SOPREMA, Inc. is a registered provider with The American Institute Of Architects Continuing Education Systems. Credit earned on completion of this program will be reported to CES Records for AIA members. Certificates of completion for non-AIA members are available upon request. This program is registered with the AIA/CES for continuing professional education. As such, it does not include content that may be deemed or construed to be an approval or endorsement by the AIA of any material of construction or any method or manner of handling, using, distributing, or dealing in any material or product. Questions related to specific materials, methods, and services will be addressed at the conclusion of this presentation.

4. Learning Objectives Review the history of vegetative systems Discuss the benefits of vegetative roof systems, including the comprehensive environmental and health and welfare benefits. Review the various components of a vegetative roof system, including the many types of plantings available and their subsequent impact on the health and welfare of building occupants. Discuss the various considerations of vegetative roof systems, including safety concerns in regards to maintenance of roof system.

5. The History of Garden Roofs

6. Garden Roof History Ancient roof gardens were installed as far back as 2020 BCE in Mesopotamia.

7. Garden Roof History Ancient roof gardens were installed as far back as 2020 BCE in Mesopotamia. Hanging Gardens of Babylon

8. Garden Roof History Ancient roof gardens were installed as far back as 2020 BCE in Mesopotamia. Hanging Gardens of Babylon Modern trend of green roofs begins in Germany Stuttgart-Weilimdorf, Germany

9. Garden Roof History Ancient roof gardens were installed as far back as 2020 BCE in Mesopotamia. Hanging Gardens of Babylon Modern trend of green roofs begins in Germany Growing popularity overseas decades ago Hotel New Otani, Tokyo, Japan

10. Garden Roof History Ancient roof gardens were installed as far back as 2020 BCE in Mesopotamia. Hanging Gardens of Babylon Modern trend of green roofs begins in Germany Growing popularity overseas decades ago Now popular throughout U.S. Chicago City Hall

11. Garden Roof Initiatives What is a green building? Design and construction practices that meet specified standards and resolve negative impacts on occupants and the environment in five broad areas: Sustainable site planning Water management Energy efficiency Conservation of materials and resources Quality of indoor environment

12. Garden Roof Initiatives Standard 189 A new minimum green building standard adopted in 2010 into the International Green Construction Code (IGCC) A collaboration between the AIA and ASTM Modeled after LEED

13. Garden Roof Initiatives Green Roofs for Healthy Cities Green Roofs for Healthy Cities’ mission is to increase the awareness of the economic, social and environmental benefits of green roofs and green walls, and other forms of living architecture through education, advocacy, professional development and celebrations of excellence. Active for over a decade, GRHC has been a major contributor to the advancement of green roofs and green technologies.

14. The Benefits of Vegetated Roofs

15. Garden Roof Benefits Converts CO 2 to O 2 25 m 2 of leaf surface produces 27 grams of oxygen per daylight period. 1 This is equal to the amount a person consumes in the same period of time. 1 www.greenroofs.org

16. Garden Roof Benefits Noise reduction Substrate blocks lower frequencies. Plants block higher frequencies. A four inch layer of growing medium can reduce sound up to 20 dB. 1 1 greenroofs.org

17. Garden Roof Benefits Natural dust filtration 10 square feet of unmowed grass absorbs up to 2 kg of windborne dust each year. 1 Minimum area of 20,000 ft 2 1 Peck and Kuhn, Design Guidelines for Green Roofs

18. Garden Roof Benefits Wildlife conservation Green roofs provide a natural habitat for indigenous species of birds and insects.

19. Garden Roof Benefits Natural water filtration Heavy metals carried by rain are bound in the roof instead of being discharged. 95% of cadmium, copper and lead are filtered out of the runoff. 1 1 City of Chicago, “A Guide to Storm Water Best Management Practices”

20. Garden Roof Benefits Reduces Heat Island Effect On a 90 degree day, a traditional roof can exceed 160°F. Under the same conditions, a green roof will typically emit a temperature of only 95°F. 160° 95°

21. Garden Roof Benefits Energy efficiency $

22. Garden Roof Benefits National Research Council Field Roofing Facility Ottawa, Ontario Constructed to scientifically test the energy efficiency of green roofs

23. Garden Roof Benefits Rooftop GardenReference Roof 9m (29.5 ft) 5m (16.4 ft) parapet 1m (3.3 ft) 8m (26.2 ft)

24. Garden Roof Benefits Rooftop GardenReference Roof Thermocouple Heat flux transducer Vegetation Growing medium Drainage layer Roof membrane Support panel Insulation Vapor control Structural support Filter membrane

25. Garden Roof Benefits Annual thermal exchanges January 1, 2001 through December 31, 2001 Heat gain reduction = 95% Heat loss reduction = 26% -1586 696 -1180 32

26. Garden Roof Benefits Energy efficiency NRC study demonstrates that green roofs reduce thermal exchanges. Yearly savings can reach 1.5kWh per square foot of green roof. $

27. Garden Roof Benefits Energy efficiency Not all structures are alike (building height, number of windows, climate zone, insulation, etc.) so this number can and will vary. $

28. Garden Roof Benefits Energy efficiency Green roof calculators can assist in determining the overall energy efficiency benefits supplied by a given garden roof system. 1 $ 1 greenroofs.org/index.php/resources/greensavecalculator

29. Garden Roof Benefits Energy efficiency Temperature differences between a reference roof and a garden roof: $

30. Garden Roof Benefits Temperature fluctuation differences

31. Garden Roof Benefits Investment protection Vegetation guards the roof membranes against: Ultraviolet radiation Extreme temperature fluctuations Heat aging Physical damage

32. Garden Roof Benefits Storm water management Green roofs reduce the amount and rate of rain water runoff. Portland, Oregon utilizes numerous storm water management solutions, including garden roofs. 1 1 portlandoregon.gov

33. Garden Roof Benefits Runoff comparison Gallons collected on a roof during six-hour storm event

34. Green Roof Components

35. Structural support/load considerations Weight of saturated green roof Environmental load Suspended or supported loads Hardscape loads Live loads

36. Green Roof Components Waterproofing membrane

37. Green Roof Components Waterproofing membrane options SBS-modified bitumen APP-modified bitumen Hot rubberized asphalt PMMA liquid membrane PVC EPDM

38. Green Roof Components Waterproofing membranes Waterproofing membrane systems can be installed in a standard configuration over insulation and recovery board or in an inverted roof membrane assembly (IRMA).

39. Green Roof Components Root barrier

40. Green Roof Components Root barrier 20-30 mil polyethylene Seamed with butyl tape Root resistant – tested according to FLL

41. Green Roof Components Insulation

42. Green Roof Components Insulation 4x8’ extruded polystyrene 1-4” thick Installed directly over root barrier Drainage grooves/channels

43. Green Roof Components Drainage mat

44. Green Roof Components Drainage mat Dimpled drain or entangled net design Lightweight option compared to gravel Water retention mats available Constant flow rates Integrated filter fabrics

45. Green Roof Components Capillary mat or moisture retention mat

46. Green Roof Components Capillary mat or moisture retention mat Most drainage mats come with water holding options. Sometimes extra water-hold capacity is needed. Vegetative mats can be hydrated from below (in lieu of drip irrigation).

47. Green Roof Components Growing medium Soil depth varies depending on plant selection. Soil composition varies by region. Soil will also vary by type: Extensive Semi-intensive Intensive

48. Green Roof Components Soil considerations Must retain volume Must drain adequately Must supply nutrients Use of filter fabric No silt that can clog fabric

49. Green Roof Components Soil content A typical mix contains: Lightweight aggregate Organics Graded sand Engineered soil ratios and mix designs utilize both mineral and organic soils and vary regionally and by supplier.

50. Green Roof Components Minimum soil depths Sedums – 1-3 inches Grasses – generally 8-10 inches Shrubs – generally 18-24 inches

51. Green Roof Components Growing medium Delivery methods Blown in place Totes Two cubic yard bags

52. Green Roof Components Vegetation Sedums Grasses Annuals Perennials Shrubs Trees

53. Green Roof Components Vegetative mats Pre-planted mats provide instant garden roof Mats come in either coconut coir or nylon entanglements Sedums are typically used as the plantings

54. Green Roof Components Tray systems Pre-planted Quick and easy to install Typical sedum plantings All trays feature drainage component, growing media and plant components

55. Green Roof Components Tray systems Trays constructed of various materials Cardboard Recycled HDPE Wood Coconut coir Recycled polypropylene

56. Types of Green Roofs

57. Extensive systems 24 lb saturated 4 inches of soil or less Grasses and sedums

58. Types of Green Roofs Extensive systems

59. Types of Green Roofs Semi-intensive systems Between 24-60 lb saturated 4-8 inches of soil Greater plant selection

60. Types of Green Roofs Semi-intensive systems

61. Types of Green Roofs Intensive systems Heavy weight (> 60 lb) 8 inches of soil or more Open plant selection

62. Types of Green Roofs Intensive systems

63. ExtensiveSemi-intensiveIntensive Weight limitLess than 24 lb24-60 lbGreater than 60 lb Thickness4 inches or less4 to 8 inches8 inches or more MaintenanceLowMediumHigh Plant selectionLow grass & sedumsGreater than extensiveOpen BiodiversityMediumMedium to highHigh CostLowLow to mediumHigh

64. Green Roof Considerations

65. Considerations Condition of existing roof Structural capacity Access to roof Project location – Hardiness Zones Purpose of roof Material availability Budget

66. Green Roof Considerations Hardiness Zones A wide variation of conditions can affect plants Heat from building Reflected light and heat Roof orientation Soil depth and moisture level

67. Green Roof Considerations Concerns Rooftop safety Excessive construction traffic Possible root damage Repair burdens Seasonal phasing Split responsibility between landscaper and contractor

68. Green Roof Considerations Irrigation Must have access to water at roof level Need initial watering to establish new plants Permanent irrigation system Hose with sprinkler and timer

69. Green Roof Considerations Irrigation Extensive and most semi-intensive green roofs can be viable without regular irrigation, depending on climate. Intensive roof systems usually require regular irrigation.

70. Green Roof Considerations Maintenance?

71. Green Roof Considerations Maintenance Low maintenance does not mean NO maintenance Weed and fertilize as necessary Trim plants and shrubs Grass may require cutting Monitor during drought conditions Check drainage regularly

72. Green Roof Considerations What if?

73. This concludes the AIA accredited portion of the presentation.

74. Questions?