1、Designation: E2777 14Standard Guide forVegetative (Green) Roof Systems1This standard is issued under the fixed designation E2777; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A number in parentheses in
2、dicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This guide identifies terminology, principles and funda-mental concepts including those related to sustainability, tech-nical requirements of construction, and
3、 types of vegetative(green) roof systems used on buildings.1.2 The considerations for sustainable development relativeto vegetative (green) roof systems are categorized as follows:environmental, social, and economic as consistent with GuideE2432. (See Appendix X1.)1.3 This guide discusses technical
4、requirements for vegeta-tive (green) roof systems pertaining to the following catego-ries: plants, media, wind scour resistance, soil reinforcement,separation or filter layers, drain layers, water retention layers,protection layers, and root penetration barriers.1.4 This guide addresses intensive an
5、d extensive vegetative(green) roof systems for roofs up to 15 % slope. Roofing/waterproofing membranes and insulation are key componentsof vegetative (green) roof systems, but technical requirementsregarding their role in such roof systems is beyond the scope ofthis guide.NOTE 1ASTM Technical Commit
6、tees E60 and C16 have jurisdictionover the development of standards for roofing/waterproofing membranesand insulations, respectively. Some of their existing standards may behelpful in the evaluation of membranes and insulation used in vegetative(green) roof systems. As these two committees develop s
7、tandards for suchroofs, this guide will be revised appropriately.1.5 The values stated in inch-pound units are to be regardedas standard. The values given in parentheses are mathematicalconversions to SI units that are provided for information onlyand are not considered standard.1.6 This standard do
8、es not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Sta
9、ndards:2,3C88 Test Method for Soundness of Aggregates by Use ofSodium Sulfate or Magnesium SulfateD1079 Terminology Relating to Roofing and WaterproofingD1987 Test Method for Biological Clogging of Geotextile orSoil/Geotextile FiltersD2974 Test Methods for Moisture, Ash, and Organic Matterof Peat an
10、d Other Organic SoilsD3786/D3786M Test Method for Bursting Strength of Tex-tile FabricsDiaphragm Bursting Strength Tester MethodD4354 Practice for Sampling of Geosynthetics and RolledErosion Control Products(RECPs) for TestingD4439 Terminology for GeosyntheticsD4491 Test Methods for Water Permeabili
11、ty of Geotextilesby PermittivityD4595 Test Method for Tensile Properties of Geotextiles bythe Wide-Width Strip MethodD4716/D4716M Test Method for Determining the (In-plane)Flow Rate per Unit Width and Hydraulic Transmissivityof a Geosynthetic Using a Constant HeadD4751 Test Method for DeterminingApp
12、arent Opening Sizeof a GeotextileD4759 Practice for Determining the Specification Confor-mance of GeosyntheticsD4873 Guide for Identification, Storage, and Handling ofGeosynthetic Rolls and SamplesD5262 Test Method for Evaluating the Unconfined TensionCreep and Creep Rupture Behavior of Geosynthetic
13、sD5617 Test Method for Multi-Axial Tension Test for Geo-syntheticsD5818 Practice for Exposure and Retrieval of Samples toEvaluate Installation Damage of GeosyntheticsD6637 Test Method for Determining Tensile Properties ofGeogrids by the Single or Multi-Rib Tensile MethodD7361 Test Method for Acceler
14、ated Compressive Creep ofGeosynthetic Materials Based on Time-Temperature Su-perposition Using the Stepped Isothermal Method1This guide is under the jurisdiction of ASTM Committee E60 on Sustainabilityand is the direct responsibility of Subcommittee E60.01 on Buildings and Construc-tion.Current edit
15、ion approved May 1, 2014. Published June 2014. DOI: 10.1520/E2777-142For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM w
16、ebsite.3Whenever a specific version of a standard is not identified, the most recentedition of the standard shall apply.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1E108 Test Methods for Fire Tests of Roof CoveringsE136 Test Method
17、 for Behavior of Materials in a VerticalTube Furnace at 750CE631 Terminology of Building ConstructionsE2114 Terminology for Sustainability Relative to the Perfor-mance of BuildingsE2396 Test Method for Saturated Water Permeability ofGranular Drainage Media Falling-Head Method forVegetative (Green) R
18、oof SystemsE2397 Practice for Determination of Dead Loads and LiveLoads Associated with Vegetative (Green) Roof SystemsE2398 Test Method for Water Capture and Media Retentionof Geocomposite Drain Layers for Vegetative (Green)Roof SystemsE2399 Test Method for Maximum Media Density for DeadLoad Analys
19、is of Vegetative (Green) Roof SystemsE2400 Guide for Selection, Installation, and Maintenance ofPlants for Green Roof SystemsE2432 Guide for General Principles of Sustainability Rela-tive to BuildingsE2788 Specification for Use of Expanded Shale, Clay andSlate (ESCS) as a Mineral Component in the Gr
20、owingMedia and the Drainage Layer for Vegetative (Green)Roof Systems2.2 ASCE/SEI Standard:4ASCE/SEI 7 Minimum Design Loads for Buildings andOther Structures (latest edition)3. Terminology3.1 Definitions:3.1.1 For terms related to building, refer to TerminologyE631.3.1.2 For terms related to sustaina
21、bility and buildings, referto Terminology E2114.3.1.3 For terms related to roofing and waterproofing, refer toTerminology D1079.3.2 Definitions of Terms Specific to This Standard:3.2.1 apparent opening size (AOS), nfor a geotextile, aproperty which indicates the approximate largest particle thatwoul
22、d effectively pass through the geotextile.3.2.2 capillary potential, nof geotextiles, a property thatindicates the ability of a geotextile to distribute moisture.3.2.3 cation exchange capacity (CEC), nthe capacity of asoil to retain and exchange the cations of nutrients, defined asthe sum of exchang
23、eable cations that a media can retain perunit weight (1).53.2.4 clogging, nfor geotextiles, the condition where soilparticles move into and are retained in the openings of thefabric, thereby reducing the hydraulic conductivity.3.2.5 dead load, nfor a vegetative (green) roof system, theweight of a ma
24、ture vegetative (green) roof system from thestructural deck up, following prolonged rainfall during whichretained and captured water attain maximum levels.3.2.6 drain layer, nhorizontal layer, including one or morediscrete components, that has been specifically designed toconvey water toward the roo
25、f deck drains, gutters, or scuppers.3.2.6.1 DiscussionDrain layers may be simple, consistingof a single component, or complex, combining multiple com-ponents including: geosynthetics, geocomposites, and coarsemineral aggregate. Drain layers are not used in single-coursevegetative (green) roof system
26、s. See also geocomposite drainlayer and granular drain layer.3.2.7 extensive vegetative (green) roof system, na roofsystem that features plants that can be sustained in shallowmedia layers (with 6 in. or less of growing media), andtypically utilizes non-woody, drought tolerant herbs, grass,moss, and
27、 succulents.3.2.8 evapotranspiration, nthe process by which water isreleased to the atmosphere by evaporation from the surface ofmedia and plant foliage, and components of the vegetative(green) roof system.3.2.8.1 DiscussionPotential evapotranspiration rates canbe determined using local climatic dat
28、a. Specific evapotrans-piration rates may vary with plant type, plant foliage density,vegetative (green) roof media composition and availability ofirrigation.3.2.9 gap-graded, adjgranular materials in which theparticle size distribution curve is markedly discontinuous.Mixtures containing particles o
29、f both large and small sizes, inwhich particles of certain intermediate sizes are wholly orsubstantially absent. See particle size distribution curve.3.2.10 geocomposite, na product composed of two ormore materials, at least one of which is a geosynthetic.3.2.11 geocomposite drain layer, ndrain laye
30、r composedof a synthetic sheet, mat, or panel.3.2.11.1 DiscussionGeocomposite drain layers may in-clude absorptive drain mats whose principle function isdrainage, but which will also contribute to water retention.Some geocomposite drain layers may incorporate reservoirs ontheir upper surfaces that w
31、ill capture water. See also granulardrain layer.3.2.12 geosynthetic, na planar product manufactured frompolymeric material used with soil, rock, earth, or othergeotechnical-engineering-related material as an integral part ofa vegetative (green) roof system as described in PracticeD4354, Practice D47
32、59, Guide D4873, Test Method D5617,and Practice D5818.3.2.13 geotextile, nany permeable textile used withfoundation, soil, rock, earth, or any othergeotechnicalengineering-related material as an integral part ofa man-made project, structure, or system.3.2.13.1 DiscussionGeotextiles perform several f
33、unctionsin geotechnical engineering applications, including: separation;filtration; drainage; reinforcement; and protection.3.2.14 granular drainage media, ncoarse aggregate ap-plied in a layer at the base of the vegetated vegetative (green)roof system profile or filled into the upper face of a rese
34、rvoir4Available from American Society of Civil Engineers (ASCE), 1801 AlexanderBell Dr., Reston, VA 20191, http:/www.asce.org.5The boldface numbers in parentheses refer to the list of references at the end ofthis standard.E2777 142sheet to provide a horizontal plane for free drainage of thevegetativ
35、e (green) roof system.3.2.15 granular drain layer, na drain layer composedentirely of granular drainage media.3.2.16 hardscape, nnon-vegetated surfacing on vegetative(green) roof systems, used in place of soil at walkways, plazas,maintenance areas, or at staging areas for mechanical equip-ment and f
36、aade access.3.2.17 hydraulic transmissivity, nfor a geosynthetic orgeocomposite, the volumetric flow rate per unit width ofspecimen per unit gradient in a direction parallel to the plane ofthe specimen; also referred to as in-plane flow, and, for agranular drainage media, saturated water permeabilit
37、y multi-plied by the layer thickness as determined using Test MethodD4716/D4716M.3.2.18 intensive vegetative (green) roof system, nintensivevegetative (green) roof systems feature large perennial plantsor turf grass.3.2.18.1 DiscussionThe use of large plants generally re-quires media thicknesses in
38、excess of 6 in. (15 cm), and in mostinstances, irrigation. Intensive vegetative (green) roofs willrequire levels of maintenance similar to onground gardens. Seealso extensive vegetated (green) roof system.3.2.19 maximum media density, nthe density of a granulardrainage media or vegetative (green) ro
39、of media determinedafter they have been subjected to a specific amount ofcompaction and hydrated by immersion to simulate prolongedexposure to both foot traffic and rainfall.3.2.19.1 DiscussionThe maximum media density appliesto drained conditions.3.2.20 module, npre-manufactured unit containing som
40、eof the functional elements of a vegetative (green) roof system.3.2.20.1 DiscussionIndependent modules are designed tobe placed adjacent, and sometimes linked to one another, inorder to cover roof surfaces.3.2.21 open-graded, adjgranular materials that containrelatively few fines in order to leave f
41、airly large spacesbetween particles when compacted. See particle size distribu-tion curve.3.2.22 organic matter, nmaterial in a soil or vegetative(green) roof media that volatilizes from a dry sample whenheated in an oven to 824F (440C).3.2.23 particle size distribution curve, ncurve, based onsieve
42、and hydrometer analysis that describes the relativequantities of particles of different sizes in a mixture.3.2.23.1 DiscussionFor planting media, this descriptor islimited to the non-organic fraction.3.2.24 permittivity, nof geotextiles, the volumetric flowrate of water per unit cross sectional area
43、 per unit head underlaminar flow conditions, perpendicular to the plane of thegeotextile.3.2.25 permeability, nsee saturated water permeability.3.2.26 phytotoxic, npoisonous to plants.3.2.27 protection layer, nany continuous layer that isintended to protect the roofing/waterproofing membrane fromdam
44、age and which is placed in direct contact with theroofing/waterproofing membrane.3.2.27.1 DiscussionAgents for damage may includeabrasion, puncture, UV exposure, and temperature fluctuation.Protection layers may include of additional layers of material(as recommended by the membrane manufacturer), c
45、oatings,geosynthetic materials, geotextiles, geocomposites, tiles, andinsulation.3.2.28 reservoir sheet, na shaped plastic membrane con-taining receptacles on its upper surface to capture and retainwater.3.2.28.1 DiscussionIn some vegetative (green) roofsystems, these receptacles are filled with gra
46、nular drainagemedia.3.2.29 root penetrability, nof a geotextile, a property thatindicates the ease with which plant roots can penetrate ageotextile.3.2.30 root penetration barrier, ncontinuous layer incor-porated in a vegetative (green) roof system to prevent damageto the roofing/waterproofing membr
47、ane system caused by rootgrowth.3.2.31 root resistance, nability of component to preventpenetration by roots as measured in a long-duration test thatsimulates field conditions (2).3.2.32 saturated water permeability, nfor vegetative(green) roof media, the coefficient which when multipliedtimes the h
48、ydraulic gradient yields the apparent velocity withwhich water at 68F (20C) moves through a cross-section offully submerged media.3.2.33 soundness, nfor granular drainage media, the ca-pacity to resist freezing without fracturing.3.2.34 thermal capacitance, na property of a material thatdetermines h
49、ow readily it absorbs and releases thermal energy(3).3.2.34.1 DiscussionHeat capacity, or specific heat, is themeasure for thermal capacitance. Heat capacity of a material isdetermined by measuring the increase in temperature thatattends the addition of thermal energy. In vegetative (green)roof systems, the material with the highest heat capacity isusually water.3.2.35 underflow, nwater derived from rainfall or irriga-tion that percolates to the base of the vegetative (green) roofsystem profile and then flows horizontally t
