Materials:CGT Hybrid (Blue-Green) Vegetated Roof System

Division C - Accepted Materials
Group - Vegetated Roof Systems

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CGT Hybrid (Blue-Green) 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) Hybrid (Blue-Green) Vegetated Roof System allow for rooftop detention underneath our Tray and Layered Green Roof systems. This hybrid system allows you to maximize your rooftop for stormwater management‐ allowing for projects that want to green the rooftop, while also providing stormwater detention. The Water Storage Unit by Columbia Green Technologies (CGT) is a made up of thin‐walled cylindrical columns injection molded of recycled resin of polypropylene for strength and durability. Water storage units are easy to cut to shape in the field, to work around irregular shapes. (Adapted from the system's technical literature) Manufacturer online resources Hybrid (Blue-Green) Vegetated Roof System System Type Extensive System Depth 212.8 mm (8.38") to 349 mm (13.38") Growing Media Depth 212.8 mm (8.38") to 349 mm (13.38") Vegetation Profile Sedum-Herbaceus-Grasses 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) CGT Sedum Mat, CGT Sedum Tile, or pre-grown vegetation in trays by manufacturer CGT Extensive Growing Media CGT 1" Water Retention Layer or Standard Water Retention Layer (Consult system manufacturer) CGT 0.375" Drainage Filter Layer CGT Geogrid CGT Water Detention Unit CGT Geotextile Fabric CGT Root Barrier Roof Assembly by roofing Contractor CGT Metal Edger †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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