Green roof gardens increase well-being and livability of The View

Van der Tol wants to use green solutions to make the city greener, healthier and more livable. For example, by promoting biodiversity, effective (re)use of (rain) water, combating the warming of the city and improving the indoor climate, all within the framework of its EcoCity vision. The View of Rotterdam is a nice calling card for this. Commissioned by developer The View of Rotterdam bv and to a design by Baljon Landscape Architects, Van der Tol realized no less than three intensive roof gardens for building Bay House: a Garden, an Inner Street and Santos Square.

'The View' is a modern development project on peninsula Katendrecht, with an interesting mix of retail, hospitality, offices and housing. The buildings offer wide views over the Rijnhaven, the Port of Rotterdam, the Kop van Zuid and Katendrecht and together form a new urban environment, in which green elements stimulate the well-being of residents and the livability of the city. Part of phase 1 is Bay House, for which Van der Tol realized three full-scale use gardens with small trees, shrubs, perennials and flower bulbs. "We were awarded this contract after a tender in which we presented an alternative technical elaboration of the aesthetic design," says Gert-Jan Middelie, Project Manager at Van der Tol. "For example, because of the slope of the roofs, we removed the retention crates from the design. In addition, we lowered the overall structure by several centimeters. For example, by replacing the retention layer with a drainage mat. This allowed for significant savings in materials, operations and lifting movements. We also worked out a more efficient solution for the corten steel retaining walls. This received a very positive response."

Construction of roof gardens

For the Garden and Santos Square, Van der Tol constructed a roof structure with a 20-mm FX 50 drainage layer, topped with approximately 35 cm of intensive substrate for the perennials and shrubs. "Along the edges of the planters, round-shaped corten steel retaining walls were mounted," says Middelie. "At the location of the paving, we additionally applied lava, on which the concrete tiles were then laid. Gravel strips were also created in several places." For the paving of the Binnenstraat, Van der Tol used height-adjustable tile supports. "This allowed the tiles to be laid perfectly level despite the roof slope." 

Excellent breeding ground

At the level of the stairs to the Garden, the tiles run into a deck of bamboo decking boards, Middelie says. "Between these decking boards and the tiles, we had corten steel planters without bottoms made, in two different heights. Also in these is an FX 50 drainage layer with intensive substrate, creating an excellent breeding ground for the perennials and bulbs." 

Green living pleasure

A nice detail is that the Inner Garden was already largely complete while construction was still in full swing. "The tulips and other bulbs were already blooming profusely while indoor plasterers and other builders were still working," Middelie said. "From the very beginning, the gardens contribute to the residents' living enjoyment and well-being. The greenery also improves the environment, providing rich biodiversity, reducing air pollution, providing water storage, dampening noise pollution and cooling in hot periods."

Beautiful and diverse project

A few weeks after completion, Middelie looks back on a beautiful project, in which cooperation with the client and all construction partners was very pleasant. But also on a technically diverse project, in which Van der Tol's expertise has come into its own.