Prefabricated construction in the Bay Area. Key role for anchors

The Robin and The Jay are two residential buildings that are part of the Bajeskwartier. Both high-rise developments are entirely prefabricated, with Loveld supplying and partially assembling the complete facade elements. An essential part of this is the mutual anchoring of the façade elements, which forms an important part of the stability of the buildings. Loveld uses classic bar anchors from Schroeder Ankers for this purpose.

On the H.J.E. Wenckebachweg in Amsterdam, a new urban district called Bajeskwartier is being developed on the site of the former Penitentiary Institution Amsterdam Overamstel. The area will contain some 1,350 social housing units and (medium) expensive rental and owner-occupied housing units, in combination with catering establishments, artists' workshops, a daycare center and a health center. A secondary school is already in operation. 

Designed by Barcorde Architecs, The Robin includes 129 owner-occupied apartments ranging from 45 to 116 m2 with a child care center in the plinth. The Jay, a design by OMA, accounts for 135 compact homes ranging from 34 to 48 m2. BAM Group is constructing both buildings with a high degree of prefabrication. Of these, Loveld is supplying the facade elements. "For this work, we are supplying complete sandwich elements with concrete inner leaf, insulation, an outer leaf with acidified concrete, window frames, glass, electrical provisions, lightning conductance and rainwater drainage," says Vincent Termote, Project Sales & Development Director for Loveld. "We give the contractor and his suppliers and subcontractors the opportunity to complete the façade elements at our factory. In this specially equipped hall, they can build the elements under optimal conditions. An important part of the work is thus moved from the unpredictable construction site to a conditioned factory, which is a great advantage for the contractor. The 24-ton elements are transported just-in-time in pairs on a flatbed trailer to the construction site."

Building with precast means a different way of transferring forces compared to cast-in-place structures. Termote: "With precast elements, torque anchors are immensely important. In terms of stability, unlike with cast-in-place facades, you don't have continuous reinforcement. At each joint, the force action is completely interrupted. This is where torque anchors come into play, not only to hold the elements in place but also to absorb the loads. Over 3,600 anchors are incorporated into both The Robin and The Jay, so it is through these anchors that the entire load transfer takes place in part. I see it as a chain of elements that have an essential role in the stability function of the building structure."

Loveld is using bar tie anchors from Schroeder Ankers for both buildings. "A total of six to eight of these are embedded at the bottom and top of the façade elements," Termote continued. "Yet another important advantage of screw anchors is the transportability of the elements. Continuous reinforcement is easier, but then the 3.40-meter-high elements would be 80 centimeters higher because of the protruding reinforcement steel, and then suddenly you can only transport one element on an inclined trailer. That's much more expensive that two on a regular flatbed trailer." 

Classic, galvanized bar anchors from Schroeder are used for the buildings in the Bay Quarter. "They are in the interior cavity walls, so in their lifetime they are well protected from weather and moisture. Then you don't need additional protection. Because the anchors in the lower layers have to handle the most loads, the heaviest versions were used there. As you go up, in say five steps, the anchors become lighter and lighter. There is no point in pouring heavy anchors everywhere if less is more than enough. The nice thing about Schroeder Ankers is that they share clear information and that we are used to the calculation methods. We like that very much."