This blended roof is covered in succulents and Minnesota natives, making it the most ecologically diverse roof in the state.
The extensive green roof on the main roof of the Target Center was completed in 2009. It was part of a contract to re-roof all the decks on the facility. At the time of design, it was the 5th largest in the USA, and remains the largest in Minnesota.
Without runoff, this green roof can retain 1.1” rain, estimating 1 M gallons per year
Project Overview
Architect
Leo A Daly
total Sq Ft
113,000
Owner
City of Minneapolis
Maintenance
AD Greenroof LLC
Project Goals & Expectations
This vegetation roof system elevated 160’ in the city grows many resources for pollinators, other insects, and birds. The existing structure only allowed for 2.75” growing media depth in the center, 3.5” at the perimeter, per structrual evaluation. It remains one of the most successful and largest green roof in the USA. Depending on the flight patterns, it is visible from an airplane!
A pre-grown succulent mat was essential for immediate coverage, however, a native forb palette was been planted via plugs and seeds and maintained. We are building a bio-dynamic soil structure for mycorrhiae to support plant life. We use a sub-drip online irrigation used as needed, which is monitored and controlled online via cellular connection. The base bid also included 20 years horticultural maintenance, ensuring a ecologically diverse and watertight roof.
The project was re-roofed in 2009 with an 80 mil PVC membrane. It is fitted with leak detection. Due to the limitations of the structrual deck, there have been a few times where snow load needed to be recalculated to handle the operational requirements inside the arena for concerts.
