Author: cristina

Blue-green roofs can transform urban stormwater management

By Cristina Senjug, Partnership Manager Next Level Stormwater Management

Innovative Blue-Green Roofs for Climate Adaptation and Resilience is a co-presentation at Grey to Green by Dr. Farzad Fahimi, Vice President at LEA Consulting and Dr. Karen Liu, Next Level Stormwater Management’s green roof specialist. Their presentation focuses on design strategies, cost-benefit analysis, and real-world performance of blue-green roofs. A Toronto green roof case study reviews an upgrade to a blue-green system to provide enhanced stormwater detention to eliminate the need for costly underground tanks.

Dr. Farzad Fahimi and Dr. Karen Liu presentation poster for Grey to Green 2025Conference

Dr. Farzad Fahimi has over 20 years experience on major environmental, municipal, infrastructure, and land development projects. His expertise spans watershed management, climate change adaptation, master planning, linear infrastructure, large-scale sewer systems, river engineering, and the integration of Green Infrastructure (GI) and Low Impact Development (LID).

Before joining the private sector, Dr. Karen Liu was a lead researcher of the green roof programs at the National Research Council and the British Columbia Institute of Technology. She led the research teams to evaluate water balance and examine stormwater management potential. Karen was a key participant in the research consortium that developed the first national wind testing standard for vegetated roofing CSA A123.24.

Canada’s Supplier of more than 2.5 Million SQFT

Next Level Stormwater Management (NLSM) is Canada’s leading supplier of high performance rooftop retention and detention solutions such as LiteN’Less™, StormCap™, Alpine Meadow and SpongeBase™. Ready to start your green roof project? The NLSM team has more than 90 years combined industry experience and here to support you at every stage from design and construction to maintenance. Please email us or call 416-637-5772 today.

Corporate Brochure | Vegetated Roofing Solutions | Stormwater Management Technologies

Next Level Stormwater Management products range from soilless extensive green roofs to intensive vegetated roofing systems, including specialized stormwater retention and detention, vegetated and non-vegetated systems.
See four (4) page corporate brochure for details.

Supplier of more than 2.5 M SQFT Coast to Coast

NLSM is Canada’s leading supplier of pre-vegetated roofs such as LiteN’Less™, Xeroflor® and StormCap™ systems. We customize to local stormwater and biodiversity requirements. Email or call (416) 637-5772 Ext 1.

NLSM Team Celebrates Award-Winning BTC Green Roofs

Next Level’s Sasha Aguilera, Design Ambassador and Sawsan Hlal, Estimating and Operations joined Dr. Karen Liu, Green Roof Specialist on the Broadway Tech Centre (BTC) in Vancouver, British Columbia on World Green Roof Day 2024.

Designed by Randy Sharp and Connect Landscape Architecture, this award-winning, LEED Platinum certified campus was built on a former brownfield. Four of the eight low-rise BTC buildings are covered with a total of 10,000 square metres of lightweight soilless vegetated roof systems. They have a combined water storage capacity of 460,000 litres, or more than 1,500 bathtubs of rainfall (based on 300 litres per bathtub). Every year, the four green roofs absorb 10 million litres of rainfall, equivalent to four Olympic sized swimming pools, feeding the plants and evaporating back to the atmosphere, thus diverting it from our stormwater infrastructure. This thin-layered system has a superior water retention-to-weight ratio. It is comprised of locally grown roll-out sedum mats with 8-10 species of drought tolerant sedum. System base layers include mineral wool and fleece as retention layers along with a drainage layer and root barrier.

BTC is winner of the Award of Excellence, Green Roof For Healthy Cities and the Design Excellence Award, CSLA

Download PDF of Case Study

Supplier of more than 2.5 M SQFT Coast to Coast

World Green Roof Day 2022

Images by Greg Van Riel, Sergej Krivenko and Terry Guscott

More Than 2.5 Million Square Feet Coast-to-Coast

NLSM is Canada’s leading supplier of pre-vegetated roofs such as the LiteN’Less™ and StormCap™ systems. We customize to local requirements. Offer warranty & maintenance support, provide stormwater calculations specific to location and building/roof type, stormwater test data & related innovative hydrologic modelling. Click here to get a quote or to design your next green roof.

Read Wind Design Process for Modular Vegetated Roofing Systems by Dr. Karen Liu and Sasha Aguilera in Construction Canada January 2021 Vol. 63 No. 1.

This article was written by Next Level Stormwater Management’s Green Roof Specialist Dr. Karen Liu and Design Ambassador Sasha Aguilera – key participants in the research consortium that developed the first national wind testing standard for vegetated roofing. It explains the Canadian Standards Association (CSA) A123.24-15 Standard Test Method for Wind Resistance of Modular Vegetated Roof Assembly and explains the three simple steps that help determine a vegetated roof’s ability to withstand and protect against wind forces.

NLSM Provides P. Eng Stamped Wind Resistance Letters. Get Started! Contact us

Watch Video of NRC and UL Testing

More Than 2.5 Million Square Feet Coast-to-Coast

NLSM is Canada’s leading supplier of pre-vegetated roofs such as Xeroflor, LiteN’Less™ and StormCap™ systems. We are your one-stop-shop. We customize to local requirements, provide wind and stormwater calculations specific to location and building/roof type, P.Eng letters, and other documentation. We offer various products & services including warranty & maintenance support. Click here to start your design.

Reinventing the Traditional Green Roof for Detention by Sasha Aguilera and Brad Garner in Construction Canada January 2019 Vol. 61 No. 7.

Reinventing the Traditional Green Roof for Detention discusses how detention green roof systems are a reliable and quantifiable rooftop stormwater management tool. The article examines how to use detention technology in dense urban areas to help owners achieve ROI by saving valuable real estate while meeting municipal requirements.

Supplier of More Than 2.5 M SQFT Coast to Coast

NLSM is Canada’s leading supplier of pre-vegetated roofs such as LiteN’Less™, Xeroflor® and StormCap™ systems. We customize to local requirements. Email or call (416) 637-5772 Ext 1.

Underutilized Roof Manages Stormwater

Download the PDF Case Study Precise ParkLink

Delivers the Ideal Solution

This lightweight and soilless green roof provided the ideal solution for Precise ParkLink’s new office building to meet Toronto’s Zoning By-law 569-2013 that requires commercial and industrial buildings to include soft landscaping to support stormwater management, biodiversity, and urban cooling.

Precise ParkLink received a variance to save valuable parking space at lot level by installing a green roof on an otherwise underutilized rooftop.

Green roofs are a useful tool in the stormwater management toolbox, especially when building in dense urban centres. They achieve water balance and quantity control to deliver strong return on investment. One such quantity control green roof is the StormCap™ Detain 3° that can help downsize or eliminate underground storage tanks and free up valuable space.

More Than 2.5 Million Square Feet Coast-to-Coast

Green Roof that Retains and Detains

Download the PDF Case Study Monza

Learn more about Project designer and vegetated system

Delivers the Ideal Solution

The StormCap™ Detain 3° green roof delivered the perfect solution for Monza Condo Residences by Benvenuto Group to meet detention storage requirements on a challenging site in Toronto. Studio TLA and LEA Consulting upgraded the orinally planned vegetated roof to the highly specialized StormCap™ Detain 3° green roof when permeable pavement and subsurface detention was not feasible and could not meet stormwater management requirements. This green roof is an ideal solution for urban infill development, and areas with a high water table. Detention reduces and dealys peak flow, helps mitigate flash floods and continues to be reliable in back-to-back, second day storms. Unlike blue roofs, StormCap™ Detain 3° friction detention works efficiently on low-sloped roofs. Customizable detention layers can store up to 100 mm (4″) of additional water on your roof. This helps downsize or eliminate the need for underground storage tanks, freeing up valuable space and delivering a strong return on investment.

More Than 2.5 Million Square Feet Coast-to-Coast

Read Designing Extensive and Semi-Extensive Vegetated Roofs for Long-term Performance by Sasha Aguilera and Kees Govers in Construction Canada July 2016 Vol. 58 No. 5.

Awarded the 2017 F. Ross Browne Award for “Article of the Year”, this article co-authored by Sasha Aguilera and Kees Govers encourages consultants and contractors to think about their designs and implementations related to vegetated roofs in such a way that systems can perform as long as the building is in use. The article discusses everything from budgeting and design, to access, irrigation, wind uplift, designing for problem areas, care during construction, post-installation, maintenance, vegetation and overburden warranties. To ensure excellence in performance, it’s important the details in design and installation are considered as critically as the systems themselves.