ASTM E2396/E2396M-19

Standard Test Method for Saturated Water Permeability of Granular Drainage Media [Falling-Head Method] for Vegetative (Green) Roof Systems

SIGNIFICANCE AND USE
5.1 This test method addresses performance characteristics for vegetative (green) roof systems with respect to the water permeability of the drainage media.  
5.1.1 Water permeability of coarse materials is highly influenced by the head conditions under which it is measured. In vegetative (green) roofs, coarse materials are frequently used to create drainage zones for percolated rainfall.  
5.1.2 This test method is intended to provide water permeability data that is relevant to this design condition that is characterized by horizontal flow under low-head. This will also allow the performance of granular drainage layers in vegetative (green) roof systems to be compared directly to alternative components, such as geocomposite drain layers.  
5.2 Determining the performance characteristics of vegetative (green) roof systems provides information to facilitate the assessment of related engineering aspects of the facility. Such aspects may include structural design requirements, mechanical engineering and thermal design requirements, and fire and life safety requirements.  
5.3 Determining the performance characteristics of vegetative (green) roof systems provides information to facilitate assessment of the performance of one vegetative (green) roof system relative to another.
SCOPE
1.1 This test method covers a procedure for determining the water permeability of coarse granular materials used in the drainage layers of vegetative (green) roof systems.  
1.2 This test method addresses water permeability under the low-head conditions that typify horizontal flow in vegetative (green) roof applications.  
1.3 This test method is suitable for coarse-grained materials with 100 % of the material retained on the U.S. #8 [2.25 mm] sieve. It is not suitable for finer-grained materials.  
1.4 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in non-conformance with the standard.  
1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and to determine the applicability of regulatory limitations prior to use.  
1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

General Information

• Status: Published
• Publication Date: 31-Jan-2019
• ICS: 65.020.20 - Plant growing
• ICS: 91.060.20 - Roofs
• Technical Committee: D08 - Roofing and Waterproofing
• Drafting Committee: D08.24 - Sustainability

Relations

• Replaces: ASTM E2396/E2396M-15 - Standard Test Method for Saturated Water Permeability of Granular Drainage Media [Falling-Head Method] for Vegetative (Green) Roof Systems
• Effective Date: 01-Feb-2019
• Refers: ASTM C29/C29M-23 - Standard Test Method for Bulk Density (“Unit Weight”) and Voids in Aggregate
• Effective Date: 01-Oct-2023
• Refers: ASTM E2114-17 - Standard Terminology for Sustainability Relative to the Performance of Buildings
• Effective Date: 01-Feb-2017
• Refers: ASTM C29/C29M-17 - Standard Test Method for Bulk Density (“Unit Weight”) and Voids in Aggregate
• Effective Date: 01-Jan-2017
• Refers: ASTM C29/C29M-16 - Standard Test Method for Bulk Density (“Unit Weight”) and Voids in Aggregate
• Effective Date: 01-Feb-2016
• Refers: ASTM E631-15 - Standard Terminology of Building Constructions
• Effective Date: 01-Mar-2015
• Refers: ASTM E631-14 - Standard Terminology of Building Constructions
• Effective Date: 01-Nov-2014
• Refers: ASTM C29/C29M-09 - Standard Test Method for Bulk Density ("Unit Weight") and Voids in Aggregate
• Effective Date: 01-Dec-2009
• Refers: ASTM E2114-08 - Standard Terminology for Sustainability Relative to the Performance of Buildings
• Effective Date: 01-Nov-2008
• Refers: ASTM C29/C29M-07 - Standard Test Method for Bulk Density ("Unit Weight") and Voids in Aggregate
• Effective Date: 01-Aug-2007
• Refers: ASTM E2114-06a - Standard Terminology for Sustainability Relative to the Performance of Buildings
• Effective Date: 01-Dec-2006
• Refers: ASTM E631-06 - Standard Terminology of Building Constructions
• Effective Date: 01-Jun-2006
• Refers: ASTM E2114-06 - Standard Terminology for Sustainability Relative to the Performance of Buildings
• Effective Date: 15-Feb-2006
• Refers: ASTM E2114-05a - Standard Terminology for Sustainability Relative to the Performance of Buildings
• Effective Date: 01-Jun-2005
• Refers: ASTM E2114-05 - Standard Terminology for Sustainability Relative to the Performance of Buildings
• Effective Date: 01-Feb-2005

Overview

ASTM E2396/E2396M-19 is a standard developed by ASTM International that outlines a test method for determining the saturated water permeability of coarse granular materials in vegetative (green) roof systems using the falling-head method. The test specifically addresses water permeability under low-head conditions typical of horizontal flow found in green roof drainage layers. Understanding the permeability characteristics supports informed decisions about structural design, system comparison, mechanical performance, and sustainability in vegetative roof construction.

This method is applicable to coarse-grained drainage materials, ensuring reliable and consistent data essential for the effective design and assessment of green roofing solutions.

Key Topics

• Water Permeability Assessment: Measures how effectively granular drainage media allow water to pass through under saturated, low-head (low pressure) conditions.
• Falling-Head Method: Utilizes a falling-head apparatus to simulate real-world drainage conditions in green roofing systems.
• Coarse Granular Materials: The method is suitable for materials with all particles retained on a U.S. #8 (2.25 mm) sieve, commonly used in green roof drainage applications.
• Comparative Data: Enables direct comparison of granular drainage materials with alternative drainage solutions, such as geocomposite drainage layers.
• Unit Systems: Supports both SI and inch-pound units; values should not be mixed in reporting to ensure conformity with the standard.

Applications

The ASTM E2396/E2396M-19 standard provides critical data and procedures for:

• Green Roof System Design: Ensuring optimal drainage to manage rainfall, prevent waterlogging, and support healthy plant growth.
• Engineering Evaluation: Providing essential data for structural engineers and designers concerning drainage layer performance.
• Product Comparison and Selection: Offering an objective basis for comparing granular drainage materials against other green roof products to select the most effective solution for specific environmental or structural contexts.
• Sustainability and Compliance: Supporting sustainable building objectives and helping stakeholders comply with building codes and life safety requirements by verifying the drainage performance characteristics of installed media.
• Quality Assurance: Assisting manufacturers and contractors in verifying that drainage products meet industry-standard permeability requirements before installation.

Related Standards

For a comprehensive approach to green roof system specification and testing, consider referencing these related ASTM documents:

• ASTM C29/C29M: Test Method for Bulk Density (“Unit Weight”) and Voids in Aggregate, relevant for determining the density properties of granular materials.
• ASTM E631: Terminology of Building Constructions, providing standard terms for clear communication in building-related disciplines.
• ASTM E2114: Terminology for Sustainability Relative to the Performance of Buildings, supporting sustainable design and construction practices.

Practical Value

Implementing the ASTM E2396/E2396M-19 test method delivers measurable benefits:

• Improved Design Accuracy: Provides reliable permeability data that enhance the predictability of green roof drainage performance.
• Benchmarking and Performance Tracking: Facilitates ongoing product quality assessments and compliance monitoring throughout the lifecycle of vegetative installations.
• Enhanced Project Outcomes: Supports healthier plant environments and extends roofing system lifespans by ensuring proper water management.

Keywords: green roof system, drainage media, water permeability, granular materials, falling-head method, ASTM standard, vegetative roof, coarse aggregate, sustainability, building performance

Standards Content (Sample)

This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation: E2396/E2396M − 19
Standard Test Method for
Saturated Water Permeability of Granular Drainage Media
[Falling-Head Method] for Vegetative (Green) Roof Systems
ThisstandardisissuedunderthefixeddesignationE2396/E2396M;thenumberimmediatelyfollowingthedesignationindicatestheyear
of original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval.
A superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope C29/C29M Test Method for Bulk Density (“Unit Weight”)
and Voids in Aggregate
1.1 This test method covers a procedure for determining the
C130 Specification for LightweightAggregates for Concrete
water permeability of coarse granular materials used in the
(Withdrawn 1954)
drainage layers of vegetative (green) roof systems.
E631 Terminology of Building Constructions
1.2 This test method addresses water permeability under the
E2114 Terminology for Sustainability Relative to the Perfor-
low-head conditions that typify horizontal flow in vegetative
mance of Buildings
(green) roof applications.
3. Terminology
1.3 This test method is suitable for coarse-grained materials
with 100 % of the material retained on the U.S. #8 [2.25 mm]
3.1 Definitions:
sieve. It is not suitable for finer-grained materials.
3.1.1 For terms related to building construction, refer to
Terminology E631.
1.4 The values stated in either SI units or inch-pound units
3.1.2 For terms related to sustainability relative to the
are to be regarded separately as standard. The values stated in
performance of buildings, refer to Terminology E2114.
each system may not be exact equivalents; therefore, each
3.2 Definitions of Terms Specific to This Standard:
system shall be used independently of the other. Combining
3.2.1 water permeability—the coefficient which when mul-
values from the two systems may result in non-conformance
tiplied by the hydraulic gradient will yield the apparent
with the standard.
velocity with which water (at 68°F) will move through a
1.5 This standard does not purport to address all of the
cross-section of media.
safety concerns, if any, associated with its use. It is the
3.2.2 wet density—the density of coarse granular drainage
responsibility of the user of this standard to establish appro-
course materials determined after immersion for 24 hours.
priate safety, health, and environmental practices and to
determine the applicability of regulatory limitations prior to
4. Summary of Test Method
use.
1.6 This international standard was developed in accor-
4.1 Thisprocedureinvolvesmeasuringthewaterpermeabil-
dance with internationally recognized principles on standard-
ity of coarse granular materials under the low-head conditions
ization established in the Decision on Principles for the
that characterize the environment in vegetative (green) roof
Development of International Standards, Guides and Recom-
systems. A falling-head technique is used. Incidental to the
mendations issued by the World Trade Organization Technical
procedure is the measurement of the wet density of the
Barriers to Trade (TBT) Committee.
medium.
2. Referenced Documents
5. Significance and Use
2.1 ASTM Standards:
5.1 This test method addresses performance characteristics
for vegetative (green) roof systems with respect to the water
permeability of the drainage media.
This test method is under the jurisdiction ofASTM Committee D08 on Roofing
5.1.1 Water permeability of coarse materials is highly influ-
and Waterproofing and is the direct responsibility of Subcommittee D08.24 on
enced by the head conditions under which it is measured. In
Sustainability.
vegetative (green) roofs, coarse materials are frequently used
Current edition approved Feb. 1, 2019. Published February 2019. Originally
approved in 2005. Last previous edition approved in 2015 as E2396/E2396M – 15.
to create drainage zones for percolated rainfall.
DOI: 10.1520/E2396_E2396M-19.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
Standards volume information, refer to the standard’s Document Summary page on The last approved version of this historical standard is referenced on
the ASTM website. www.astm.org.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
E2396/E2396M − 19
5.1.2 This test method is intended to provide water perme- 7. Conditioning
ability data that is relevant to this design condition that is
7.1 Before conducting the tests, with the sieve in place, fill
characterizedbyhorizontalflowunderlow-head.Thiswillalso
the apparatus with water and determine the elapsed time in
allowtheperformanceofgranulardrainagelayersinvegetative
seconds that it takes for the water level to fall 6 in. [15.2 cm]
(green) roof systems to be compared directly to alternative
to the first mark. This value will be used to establish the upper
components, such as geocomposite drain layers.
limit on the measurement of water permeability using the
5.2 Determining the performance characteristics of vegeta- apparatus.
tive (green) roof systems provides information to facilitate the
8. Procedure
assessment of related engine
...

This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation: E2396/E2396M − 15 E2396/E2396M − 19
Standard Test Method for
Saturated Water Permeability of Granular Drainage Media
[Falling-Head Method] for Vegetative (Green) Roof Systems
This standard is issued under the fixed designation E2396/E2396M; the number immediately following the designation indicates the year
of original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval.
A superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope
1.1 This test method covers a procedure for determining the water permeability of coarse granular materials used in the drainage
layers of vegetative (green) roof systems.
1.2 This test method addresses water permeability under the low-head conditions that typify horizontal flow in vegetative
(green) roof applications.
1.3 This test method is suitable for coarse-grained materials with 100 % of the material retained on the U.S. #8 [2.25 mm] sieve.
It is not suitable for finer-grained materials.
1.4 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each
system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the
two systems may result in non-conformance with the standard.
1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility
of the user of this standard to establish appropriate safety safety, health, and healthenvironmental practices and to determine the
applicability of regulatory limitations prior to use.
1.6 This international standard was developed in accordance with internationally recognized principles on standardization
established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued
by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
2. Referenced Documents
2.1 ASTM Standards:
C29/C29M Test Method for Bulk Density (“Unit Weight”) and Voids in Aggregate
C130 Specification for Lightweight Aggregates for Concrete (Withdrawn 1954)
E631 Terminology of Building Constructions
E2114 Terminology for Sustainability Relative to the Performance of Buildings
3. Terminology
3.1 Definitions:
3.1.1 For terms related to building construction, refer to Terminology E631.
3.1.2 For terms related to sustainability relative to the performance of buildings, refer to Terminology E2114.
3.2 Definitions of Terms Specific to This Standard:
3.2.1 water permeability—the coefficient which when multiplied by the hydraulic gradient will yield the apparent velocity with
which water (at 68°F) will move through a cross-section of media.
3.2.2 wet density—the density of coarse granular drainage course materials determined after immersion for 24 hours.
This test method is under the jurisdiction of ASTM Committee D08 on Roofing and Waterproofing and is the direct responsibility of Subcommittee D08.24 on
Sustainability.
Current edition approved June 1, 2015Feb. 1, 2019. Published July 2015February 2019. Originally approved in 2005. Last previous edition approved in 20112015 as
E2396 – 11.E2396/E2396M – 15. DOI: 10.1520/E2396_E2396M-15.10.1520/E2396_E2396M-19.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
The last approved version of this historical standard is referenced on www.astm.org.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
E2396/E2396M − 19
4. Summary of Test Method
4.1 This procedure involves measuring the water permeability of coarse granular materials under the low-head conditions that
characterize the environment in vegetative (green) roof systems. A falling-head technique is used. Incidental to the procedure is
the measurement of the wet density of the medium.
5. Significance and Use
5.1 This test method addresses performance characteristics for vegetative (green) roof systems with respect to the water
permeability of the drainage media.
5.1.1 Water permeability of coarse materials is highly influenced by the head conditions under which it is measured. In
vegetative (green) roofs, coarse materials are frequently used to create drainage zones for percolated rainfall.
5.1.2 This test method is intended to provide water permeability data that is relevant to this design condition that is characterized
by horizontal flow under low-head. This will also allow the performance of granular drainage layers in vegetative (green) roof
systems to be compared directly to alternative components, such as geocomposite drain layers.
5.2 Determining the performance characteristics of vegetative (green) roof systems provides information to facilitate the
assessment of related engineering aspects of the facility. Such aspects may include structural design requirements, mechanical
engineering and thermal design requirements, and fire and life safety requirements.
5.3 Determining the performance characteristics of vegetative (green) roof systems provides information to facilitate assessment
of th
...