Story

This project is a component of  East Grand Rapids Municipal Complex on the shores of Reeds Lake.  It won the 2007 Project of the Year award from the American Public Works Association.  The Municipal Complex is comprised of three two-story buildings with a one-story City water reservoir located between them.  The roof of the reservoir provides a plaza overlooking the lake at the second story height. 

Recent changes in the municipal water system eliminated the need for the reservoir. 

The roof of the reservoir leaked badly, and a new roof, which also served as a plaza deck, needed to be installed. 

The 21495 sq. ft. area of the plaza drained through downspouts directly into the lake.  In its history as a concrete surface the plaza, encircled with cyclone fence,  was a visually austere and uninviting space. 

Cox Medendorp Olson Architects studied several options to provide a people friendly plaza with a watertight roof system. 

Considerations included the structural capacity of the deck roof, structural movement of the concrete deck, longevity and types of roofing systems, and different materials for plaza pavers.   A strong consideration in the selection and design of optional systems was the environmental impact of the materials and their installation. 

The final design provides pedestrian walking and sitting areas blended with garden areas.  The garden areas are soft edged to break up the straight lines of the plaza perimeter and contrast with the buildings shapes.  The garden areas also break up the expansive feel of the plaza. 

The overflow drains convey water through the face of the building wall and onto the grade.  The overflow drains only function when there is a problem with the main drains, so that any flow in the overflow drains is a wake up call to check the main drains. 

The 13,239 square feet of pedestrian pavers are a Carlisle Rubber Company product made from recycled tires.    It is estimated that approximately 10,500 to 14,000 tires are recycled into the project. 

The garden or green areas are an assembly of products by the Carlisle Rubber Company.  Starting with a 60 mil. directly adhered EPDM membrane over the polyisocyanurate insulation.  Immediately on top of the membrane roof is a root barrier, a moisture retention mat, a ½” thick dimpled plastic drainage course with a geo-textile fabric facing and then a specialized soil mix. 

The garden areas are planted in with four different species of Sedum, approximately 8,250 plants.  These different species gives a random texture and color to the garden area.  The gardens take a minimum amount of watering in the long summer dry spells, and once established are almost maintenance free and drought resistant.  The hardy nature of the plants require minimum fertilizer. 

The garden areas contribute to storm water retention.  Studies have shown the soil will retain 50% to 75% of the water in a 1-inch rain event.  This will reduce the amount of run-off to the lake through the roof drain system.  Also the run-off from the Green Roof is filtered through the soil.