October 2011 - The Watervilla de Omval, a modern interpretation of a houseboat, rests like a sleek waterbird on the Amstel River in Amsterdam. The floating structure is the brainchild of Amsterdam-based +31Architects. The multidisciplinary company combines architecture with interior design and urbanism. The project team developed the concept for customers who want the unique experience of living on the water but steer clear of the caravan-type appearance of conventional houseboats. According to the project team, customers want an open floor plan that optimizes their views of the water along with their outside space. The design also takes into account the new approach by government and urban planners to manage the Netherlands’ land development.

Land underwater
According to the BBC News, the Netherlands spans 16,164 square miles and has more than a quarter of its total area under sea level. Dikes and dunes protect the land against flooding but climate changes, rising rainfall and burgeoning rivers present new challenges. Because sea level is now higher, water has nowhere to go except inland.

In lieu of more dikes, one solution favors regulating flooded land by constructing large water basins. The water basins lend themselves to attractive urban development that also helps create a buffer during the rainy season. The only restriction is the structures supporting urban development must float. 

Two construction principles—one based on a ship and the other a pontoon—meet this criterion. The company chose the ship principle, a hollow concrete box open at the top. The hollow box also allows use of the space within as part of the building. The construction attaches to the quay with a flexible connection that permits the houseboat to rise with the water during tide changes. The floating system also can be moved on short notice without leaving an environmental footprint.

The structure’s façade has a curved line, a design element that met customers’ living space needs as well as the restriction prohibiting structures from rising more than 10 feet above the water line. Reynobond aluminum composite white cladding comprises the exterior. The material is made of two strong sheets of corrosion-resistant aluminum permanently bonded to a thermoplastic core. The material’s strength-to-weight ratio is nearly double that of steel. Panels are easy to fabricate and readily adapt to accommodate challenging interior and exterior design profiles including dramatic curves, sharp angles and trapezoidal shapes.

Bending aluminum 
“It was really difficult to make round shapes without making any concession to the design,” says Jorrit Houwert, co-founder of +31Architects. “For instance, the profiles of the aluminum windows had to be bent in these rounded shapes as well as follow the shape of the façade and the steel beams in the roof. Problems never stop coming when you start with rounded forms. But for this you need an architect, I think.”

The contemporary floating house offers occupants approximately 2,120 square feet of living space. The open kitchen and living area are located on the waterfront. In addition to a panoramic view, this arrangement provides access to the houseboat’s floating terrace. The bedroom is positioned on a split level, which introduces an open path to the ground floor of the structure, but also makes room for a terrace on the houseboat’s south side without exceeding the maximum building height. White plastered walls and ceilings follow the curve of the façade, making the transition from exterior to interior seamless.

The architects completed the houseboat in 2010. According to Houwert, the customers who purchased the floating home get a lot of positive reactions and have reported passersby knocking on the windows asking to enter the boat. The Watervilla de Omval has been nominated for the Gouden AAP 2011, Amsterdam Architecture Prize for the best building realized in 2010-2011. MM