Parisian roof terrace at the Pavillon d’Armenonville

The Pavillon d’Armenonville is located at the edge of the Bois de Boulogne, a city forest and park in the 16th arrondissement in the west of Paris, only a few minutes from the Champs-Élysées. This historic building from the 17th century was originally built as a hunting lodge by Joseph Fleuriau d’Armenonville who was responsible for the royal hunt. After its destruction in the 19th century, it was rebuilt by the French architect, Gabriel Davioud, as an inn for the riders and coachmen passing through the Bois de Bologne. The Pavillon d’Armenonville has retained its refined architecture through the ages. Today, the historic facade, the high ceilings, together with the elegant lounges fitted with state-of-the-art event technology, provide a magical location for all types of events for up to 2,000 guests. Catering and event manager, Butard Enescot, who has other exclusive premises in Paris and Provence, is part of the Butard Paris Group of companies. In addition to a professional commitment to quality, creativity and authenticity, this family company, founded in 1995, places great value on protecting the environment. The green roof has been there since 2001 and was redesigned in 2018 as part of a conversion.  This delightful roof terrace was designed by architects Fabrice Drain and executed by Ecovegetal, the experienced ZinCo partner.

Good things are at our fingertips

Strictly speaking, there’s nothing more natural than growing the ingredients for your culinary delights directly on your own roof, because 100% fresh means 100% flavour. With its special Urban Farming system build-up, ZinCo provided precisely the right technology for growing the required crops. This build-up allows for the use of different types of drainage element, depending on the type of plant, for example, a tomato plant has different irrigation needs to perennial herbs. A total of 180 m² of the 515 m² of the roof terrace area are covered with plant beds. Of this,
70 m² are used for vegetables, fruits and herbs and 110 m² are used for thriving flower species that can also be used in cooking. An incredible 660 plants grow in the 26 plant beds, which are made of pine wood, similar to the surrounding terrace decking. The overall visual structure is created by the rectangular plant beds, arranged evenly in two sizes and two in a row, and by the layout of the plants there, because even cabbage grows in neat rows. Ingenious design

The first layer of the system build-up Urban Farming to be installed onto the root-resistant waterproofed roof for all plant beds is the Protection Mat ISM 50. In 13 of the plant beds this was followed by the drainage and water storage element Aquatec^® AT 45, which is a very efficient and inexpensive solution for the greater irrigation needs of annual vegetable plants. The principle is based on the distribution and storage of water in the cells of the Aquatec^® elements, this alone reaching a volume of about 17 l/m². Dripperlines clipped into the elements, provide for a supply of water in the event of a lack of precipitation. The Wicking Mat DV 40 is then installed and its dripperlines draw the water upwards by capillarity, therefore supplying it to the substrate directly in the root area. This is the crucial point, as Pierre Georgel, owner of Ecovegetal knows: “Our years of experience with this capillary irrigation has shown us that the root system of plants with this system is three to five times more dense than is the case with conventional irrigation.”

In addition, 50% of the water supply is sufficient, for example, in comparison with irrigation from above with lawn sprinklers, where much of the water evaporates on the surface. Ecovegetal has developed a particularly light substrate specifically for growing vegetables. Using the company’s own silo truck, it was blown onto the roof, directly onto the plant beds, and distributed there. 20 m³ of substrate were needed for the required substrate depth of 25 cm.

Tailored to the needs 

While perennial herbs and flowers are not as thirsty as some young vegetables, an efficient irrigation system is nonetheless required here during arid periods. Therefore, for the remaining plant beds, the drainage mat Fixodrain XD 20 is installed in combination with Aquafleece AF 300. The high capillary-effect Aquafleece consists of two layers. The dense fabric on the underside of the Aquafleece only lets the water drip through when the upper side of the fleece is totally saturated. The dripperlines attached to the fleece ensure that there is always sufficient water available for the plants during dry periods. Approximately 26 m³ of substrate with a greater mineral content allow for the required substrate depth here of
15 cm on average. Perfect conditions for everything to grow and thrive. This makes many a crow in the forest happy, as they come to pinch the odd treat.

So much more than a visual treat 

Urban farming has so much more to offer than just culinary delights and great optics. This green roof also provides for the thermal protection of the roof waterproof membrane, noise reduction, rainwater retention and climate mitigation. It also goes without saying that it is good for biodiversity, that is to say, the variety of species and the conservation of fauna and flora. Last but not least, the roof terrace provides an eclectic space for memorable events. In any case, there is no shortage of creative ideas for a lofty reception, a floral wedding celebration or a night-time roof party in this wonderful setting.

Author
Federico Cefalu, Export Area Sales Manager, ZinCo GmbH

Plant list (selection)

Herbs:
Curry plant, rosemary, lavender, thyme, fragrant giant hyssop, sage, mint, lemon balm, basil, chives, bay leaves

Vegetables:
Artichoke, rhubarb, sorrel, celery, parsley, tomatoes, carrots, beans

Flowers:
Stonecrop, sunflower, evening primrose, viola tricolor

Fruit:
Black currants, gooseberries, raspberries, apple tree

Site board

Construction project:
Urban Farming roof at Pavillon d‘Armenonville, Allée de Longchamp, Bois de Boulogne, 75116 Paris, France

Client:
Butard Enescot, 75116 Paris, France

Construction year:
2018

Roof area:
approx. 515 m²

Green roof build-up:
ZinCo system build-up Urban Farming with Aquatec AT 45 and Fixodrain XD 20

Architect:
L‘Agence Fabrice Drain Architectures, 76000 Rouen, France

Green roof contractors:
Ecovegetal, 28410 Broué, France

System supplier:
ZinCo GmbH, Lise-Meitner-Straße 2, 72622 Nürtingen, Germany