A multi-level green roof to beautify a college campus building

  • Sedum mats with fescue highlights
  • Sedum mats in summer bloom
  • Sedum mats in bloom 2
  • Courtyard green roof with OTF planters
  • Courtyard green roof with fescue highlights
  • OTF planters and courtyard green roof
  • Upper green roof in bloom
  • Fescues and sedum blooms
  • Sedums blooming and fescue features
Sedum mats with fescue highlights1 Sedum mats in summer bloom2 Sedum mats in bloom 23 Courtyard green roof with OTF planters4 Courtyard green roof with fescue highlights5 OTF planters and courtyard green roof6 Upper green roof in bloom7 Fescues and sedum blooms8 Sedums blooming and fescue features9

Douglas College Campus Building

Douglas College wanted to add a green roof to an existing 5-story campus building in downtown New Westminister, BC. Their goal was to do something about something, and save money on something at the same time. Summarize their goals and how this project addressed them.

The block-long building is on a steep hill, so has a multi-level design. This required installing 7 separate green roofs to cover all the rooftops - 15,500 square feet in total. Architek provided the expertise, materials and installation for the project, working closely numerous stakeholders.

Green Roof Design & Functionality

Many of the building's 7 roofs can be seen from windows on the same or higher floors. Some roofs are also adjacent to outdoor seating areas and rooftop walkways. This made the roofs' aestetics very important, so 11 different plants plus some accessories were used to add color and flair.

Some of the roofs were planted with a mix of something, something and something sedums that turn into an explosion of color each fall when they flower. Other roofs use a mix of low sedums, tall native grasses and bright something, emulating a beautiful spring meadow. Old Town ceramic planters containing small trees were added around some of the seating areas to add to the park-like feeling of the roofs.

Project Overview

Client Douglas College
Project Extensive Green Roof retrofit on an existing instituational building
Location Royal Avenue, New Westminster, BC
Completed: September 2010
Cost per Sq.Ft. $15,50, including installation
Warranties RCABC + Zinco Canada, 10 years on membrane + 5 years fit for function on living roof

Products, Materials & Methodologies

Green Roof System

  • Zinco green roof build-up: Floradrain FD 25 - mutliple areas

Grow Medium & Planted Materials

  • Sempergreen pre‐grown sedum mats with 11 sedum species in mix.
  • Grow medium from Sumas Grow Media specified @ 100mm by Architek/Zinco Canada.

Roof System Build-up  (top-down)

  1. Plant materials
  2. Grow media, ZinCo Extensive, 26cm depth
  3. Filter sheet, ZinCo SF
  4. Drainage element: Zinco Floridrain ® FD 25
  5. Moisture protection, ZinCo Mat SSM 45
  6. Root protected waterproofing
  7. Roof construction


People & Organizations Involved

SOMETHING Architect CJP Architects
Landscape Architect PWL Landscape Architects
General Contractor Dominion / Stuart Olsen
Roofing Consultants Architek SBP, Raven Roofing
Green Roof Installation Architek SBP
Horticulturist Architek SBP
Growing Medium Consultants Architek SBP, Sumas Grow Media, Zinco Canada
Technical Consulting Architek SBP, Zinco Canada
MEP Engineering Zinco Canada