This practice addresses performance characteristics for vegetative (green) roof systems with respect to the dead load and transient water load of the entire vegetative (green) roof system.

Determining these 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.

Determining these performance characteristics of vegetative (green) roof systems provides information to facilitate assessment of the performance of one vegetative (green) roof system relative to another.

1. Scope

1.1 This practice covers a standardized procedure for predicting the system weight of a vegetative (green) roof system.

1.2 The practice addresses the loads associated with vegetative (green) roof systems. Components that are typically encountered in vegetative (green) roof systems include: membranes, non-absorptive plastic sheet components, metallic layers, fabrics, geocomposite drain layers, synthetic reinforcing layers, cover/recover boards, insulation materials, growth media, granular drainage media, and plant materials.

1.3 This practice also addresses the weight of the vegetative (green) roof system under two conditions: (1) weight under drained conditions after new water additions by rainfall or irrigation have ceased (this includes the weight of retained water and captured water), and (2) weight when rainfall or irrigation is actively occurring and the drain layer is completely filled with water. The first condition is considered the dead load of the vegetative (green) roof system. The difference in weight between the first and second conditions, approximated by the weight of transient water in the drain layer, is considered a live load.

1.4 This practice does not address point or line loads associated with architectural elements that are not essential components of a particular vegetative (green) roof system. These architectural elements may include pavement, walls, and masonry, and so forth.

1.5 This practice does not address live loads associated with construction activities.

1.6 This practice does not address loads associated with snow or wind.

1.7 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.

1.8 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 and health practices and to determine the applicability of regulatory limitations prior to use.

2. Referenced Documents (purchase separately) The documents listed below are referenced within the subject standard but are not provided as part of the standard.

ASTM Standards

E11 Specification for Woven Wire Test Sieve Cloth and Test Sieves

E631 Terminology of Building Constructions

E2114 Terminology for Sustainability Relative to the Performance of Buildings

E2396 Test Method for Saturated Water Permeability of Granular Drainage Media [Falling-Head Method] for Vegetative (Green) Roof Systems

E2398 Test Method for Water Capture and Media Retention of Geocomposite Drain Layers for Vegetative (Green) Roof Systems

E2399 Test Method for Maximum Media Density for Dead Load Analysis of Vegetative (Green) Roof Systems

Keywords

dead load; live load; sustainability; vegetative (green) roof; vegetative (green) roof system; vegetative (green) roofing system; water retention: Dead load; Green roof systems; Live load; Water retention;

ICS Code

ICS Number Code 65.020.20 (Plant growing); 91.060.20 (Roofs)

Citing ASTM Standards

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