Expansion on roof in Amsterdam

For a family that wanted extra space at their apartment in the center of Amsterdam, Nieuwe Architecten designed an extension on the roof. "An inner city extension within a protected cityscape which better the quality of living ", according Nieuwe Architecten. Pieters Bouwtechniek is the structural engineer of this unique project.

The building was built around 1920 and is an apartment building. The existing house on the third floor is expanded. The existing masonry extension on the roof floor is extended with a new bedroom. The remaining part of the existing roof is used as a roof terrace. To save as much weight as possible the new construction of the extension is made of a timber frame construction (HSB) elements. The HSB elements consist of wooden posts with front and rear double layer plywood. The HSB elements and the glass wall are attached to steel beams. The steel beams are spanned from building wall to building wall and should be kept free of the existing wooden beam.

The existing roof construction has been checked. The existing wooden beam layer can not absorb the loads of the extension and the roof terrace and is therefore reinforced. The reinforcement consists of a new wooden beam layer with 18 mm plywood and is fitted in connection. The multiplex provides the disk effect.

The steel beams are undercut with a low-shrink mortar K70. In addition, the steel beams provide a link with the new steel columns. The steel columns, in combination with the HSB façade elements, carry the new wooden roof. The roof also consists of a wooden beam layer with 18 mm plywood and has to be applied in connection. The multiplex provides the disk effect.

The structure is set back in relation to the building line, so that it is not visible from the street. Balustrades are designed to be as slender as possible and are also hidden from sight by the raised existing parapet on the street side.

Nieuwe Architecten made a nice video of the project.

Nieuwe Architecten - Living In The Sky from Nieuwe Architecten on Vimeo.