Materials:CGT Intensive Layered Vegetated Roof System

Division C - Accepted Materials
Group - Vegetated Roof Systems

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CGT Intensive Layered Vegetated Roof System
by Columbia Green Technologies LLC

System/Material Acceptance and Product Details The information published in the RCABC Roofing Practices Manual and offered below does NOT represent a complete set of the manufacturer’s data or specifications, nor is this system and its various materials recommended or endorsed by the Guarantor. The preparation of a detailed specification is the responsibility of the Design Authority.

Vegetated Roof System Manufacturer https://columbia-green.com/ Accepted for the RoofStar Guarantee Program June 11, 2026 Accepted for application in Vegetated Roof Systems Acceptance Criteria Refer to the RGC Standard for Vegetated Roofs System Summary The Columbia Green Technologies (CGT) Intensive Layered Vegetated Roof System is a deeper media system designed for plant material, including perennials, shrubs and trees. Columbia Green Intensive growing media is used in this system. The Intensive system offers considerable design flexibility. It consists of a root barrier, drainage layer, filtration layer, and optional water retention layer. This system can be used in any landscape design, installed on the roof or in large planters. It is easy to install‐ layers can be cut in the field to fit curves and irregular shapes. The Intensive Layered Vegetated Roof System is designed to retain water and decrease stormwater runoff. Once saturated, any excess water moves efficiently through the system and to the nearest roof drain. The system promotes plant health, allowing airflow in the drainage layer and through the media. The underlying membrane is protected with a Columbia Green root barrier. Growing media depths are based on root space requirements for plant material selected, structural requirements, and stormwater retention goals. Depths typically range from 204.2 mm (8”) to 1219.2 mm (48”)+. (Adapted from the system's technical literature) Manufacturer online resources CGT Semi-Intensive Layered Vegetated Roof System CGT Intensive Layered Vegetated Roof System System Type Intensive† System Depth 228.6 mm (9") to 1549.4 mm (61") Growing Media Depth 203.2 mm (8") to 1524 mm (60") Vegetation Profile Turf-Perennials-Woody Plants-Trees Suitable climate zones All BC zones, subject to manufacturer's approval System Components* In the usual order, from top to bottom; click on link for Technical Data Sheet (TDS) Plants-Trees-Shrubs-Ground cover (Selected by designer) Semi-Intensive Growing Media or Intensive Growing Media Water Retention Layer - Optional CGT 0.75" Drainage Filter Layer CGT Root Barrier Roof Assembly by roofing Contractor CGT Metal Edger CGT Drain Box †Guarantor's Notes Systems labeled "Inverted" are designed for a protected membrane roof assembly, also known as an inverted roof assembly. While Semi-intensive and Intensive vegetated roof systems are limited to only protected membrane roofs (See the Sentence 1.1.3.2.(5) in the "RGC Standard for Vegetated Roofs"), some vegetated roof system manufacturers offer their systems for conventionally insulated roofs. To request a written Variance to the published limitation, follow the requirements in Article 1.1.3.6.. *Conditions and Limitations Note that system thickness is dependent upon the selection of components, which is determined (in part) by design parameters, including hydrological requirements. Consult with the vegetated roof system manufacturer for options and saturated system weight. Also note that vegetation coverage under the RoofStar Vegetated Roof Guarantee applies only to extensive systems planted with mats or trays - see Part 3 of Division A for more about coverage.

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