In English | Issue 3/2021

“Portus” – high standard of concrete architecture

“Portus” – high standard of concrete architecture
Photo credit: Sami Saastamoinen

Residential building complex Portus, which was completed in August in the Verkkosaari area of Helsinki’s Kalasatama neighbourhood by the sea, has copied its design language from large luxury cruise vessels. The ornamental relief patterns on the concrete facades depict marine topics. With the complex standing partly on top of the sea, special requirements applied to the demanding foundation conditions and watertightness of the base slab.

The Portus town block located near the Kalasatama shopping mall and metro station provides luxury housing to the residents, with a private shoreside sauna, swimming dock and marina.

The original draft of the town plan specified brick as the facade material, but the developer and the architect together with construction supervision ended up choosing an impressive facade of high standard in white concrete, with relief patterning. The name of the area, Verkkosaari – Net Island in English – gave the idea of a netted pattern running decoratively in the lower parts of the facade, transforming first into waves and then into birds as it ascends up the wall.

The external walls of the building are built with concrete sandwich panels featuring a relief surface produced by pouring the outer envelope layer against a relief mould. The long horizontal strips of the facade are of ground white concrete and interspersed by continuous lines of windows and coloured building panels. The entrances to stairwells are accentuated by colourful glass panels. The roof form of the building is a flat roof, and the roof of the six-storey building part was implemented as a green roof.

The building stands on foundations consisting of drilled steel piles anchored to the rock with anti-corrosion bar anchors and strand anchors.

In the sea, the foundations have been designed taking ice loads into consideration. The structures were also built as watertight structures up to flood height.

The surfaces and access routes in the courtyard structures of the complex feature bleached concrete.

Read the entire article in Finnish and see the images >>