VERTICAL Sloterdijk will encourage biodiversity

With a sophisticated water management system, façade gardens and green roofs, the 78-meter-high high-rise in Amsterdam Sloterdijk will form an ecological connection in the green zone between Lange Bretten and Westerpark. "Every floor of the building is connected to greenery," says client manager Casper Korteweg of Van der Tol.

The climate-proof city is a hot topic in the densely built-up Randstad. Besides a few buildings in Milan (residential towers by Stefano Boeri), the Trudo Tower in Eindhoven (under construction) and Utrecht's Wonderwoods (under development), there is as yet little experience with high-rise greenery on this scale. According to designer DS Landschaparchitecten, the façade gardens and green roofs of the 168-unit owner-occupied VERTICAL, encased in a high-rise and a low-rise tower equipped with nesting boxes for birds and bats and an essential water storage function, stimulate flora and fauna in the construction area. The "vertical gardens" are part of the so-called Bretten Clay. The greenery will be pulled into the city and Sloterdijk-Centrum will become part of an ecological zone from Spaarnwoude to the ring of canals.

Water storage

Korteweg: "Van der Tol specializes in the development and implementation of green projects with a large functional component, in cooperation with Mastum Daksystemen (roofing contractor; ed.) under the Life on Roofs guarantee system. First of all, water storage is an ambitious part of the plan: all rainwater should be retained on the plot." Gardener and groundsman Van der Tol has realized several specials in the field of high-quality building greenery, such as the ingenious roof garden of the Depot Boijmans van Beuningen in Rotterdam. VERTICAL is an entirely different project from MVRDV's Depot with rooftop greenery. "Each floor is customized. In traditional construction, rainwater should go to the sewer as quickly as possible; in this project, all the rainwater is collected in the different layers of the roof garden structure. It is ideally equipped to absorb summer downpours."

Native species

The soft side, the planting of the building and the in itself challenging proposition of "green" high-rise buildings, thus also has its hard side, the technology that makes it possible. "That combination is our specialty," Korteweg said. "For VERTICAL, we supply a complete water management system, with green roofs on which we offer a 10-year waterproofing guarantee." Construction will begin this spring for Van der Tol; completion of the buildings is anticipated by client Heijmans Vastgoed by the end of 2022. "We now advise in the direction of further implementation and determination of the final planting, based on increasing biodiversity based on native species. The residents of VERTICAL will soon be surrounded by greenery on every floor."  

'All rainwater is collected in the different layers of the roof garden structure'