Industrial national monument gets 7,000 sq. m. of color concrete roof panels

Right on the Amsterdam IJ is the former shipyard of the Nederlandsche Dok en Scheepsbouw Maatschappij (NDSM). In this urban district in the making, the monumental welding shed is currently being transformed into an international cultural hotspot with the world's largest (6,500 m²) Street Art Museum. Especially the roof had to be modified.

The "cathedral of NDSM" this location was also called. The place where giant ship parts used to be welded together that then rolled out of the immense blue doors as ships or hulls. It is a rectangular, tall industrial hall with closed brick facades, square cross windows and a flat roof enlivened by four flattened gabled roofs in the width direction, which serve as skylights.

Monumental industrial heritage becomes largest
Street Art Museum.

But before the "cathedral" could become a museum, some changes had to be made, especially the roof. The industrial heritage's 1952 bima-concrete roof leaked, was not safe and therefore needed to be replaced. It had to be roof panels with the same look, size, color and the lightest possible construction. Reason why BMB development (Mediawharf bv) approached Betonfabriek Nigtevecht some three years ago to produce the 2000 x 500 mm roof plates to be replaced. A request that suited the concrete factory, located between Amsterdam and Utrecht. For more than 60 years, the company has been producing a wide range of concrete products using the 'direct-dismantling system'. The advantages are larger quantities per production day, thus quick turnaround/delivery times and cost savings. The company works largely on the basis of customer specifications. After various discussions and calculations, it was decided to apply roof panels 1,000 mm wide, with a false joint that optically retained the original dimensions, but required half as many installation operations.

Ochre yellow to ensure the original color

Years of welding work in the former welding hall had resulted in the rising welding fumes against the bims concrete roof panels leaving an ochre-yellow color. So came the request to maintain this color and apply the same pigment to the inside of the roof plates. The production process of Betonfabriek Nigtevecht allows both through-and-through pigmentation of concrete products and the application of polymer modified cementitious mortar in various colors, including the desired ochre yellow. This option was chosen by Monumentenzorg. Construction company Regiobouw Haarlemmermeer then professionally installed the roof panels.