The Watervilla, a prototype
floating house designed by architect Herman Hertzberger,
is supported like an oil rig, on a frame of hollow steel
tubes. Inhabitants can reorient the house to optimize
its solar orientation.
Photography: © Patrick
For centuries, the Dutch have shown great ingenuity
in keeping the water that surrounds their low-lying country at bay.
That's allowed them to preserve land on which to build housing for
the dense population of the Randstad, the crescent that runs from
Amsterdam to Rotterdam. Dutch architect Herman Hertzberger has turned
the idea on its head by putting houses in the water. Of course,
there have always been houseboats in Holland. The architect says
traditional Dutch houseboats were his inspiration, but notes that
as places to live these quaint, colorful anachronisms look better
than they work. They're uncomfortabletoo much boat and not
enough house, he says.
Hertzberger's Amsterdam-based Architectuurstudio
designed its first watervilla back in 1986. It floated
on foam-filled concretenot exactly a traditional material.
Since then, the studio changed the floating foundations from foam-filled
concrete to buoyant steel tubes, inspired by off-shore oil rigs.
It was necessary to change the structural system because we
wanted the house to float freely in the water and be able to change
orientation, explains project architect Patrick Franzen. The
design also nearly doubled in size from 80 square meters to 156
square meters, or about 1,680 square feet. (The updated model can
be expanded up to 200 square meters, while the original design was
fixed.) Most important, the firm was able to build a prototype of
the revised house in De Veersche Poort, located in Middelburg in
southwestern Holland, which will eventually be home to six Watervillas.
The developer of De Veersche Poort commissioned the prototype's
Like oil rigs, the Watervilla floats on a hexagonal
frame of six 10-millimeter-thick hollow steel tubes roughly 2 meters
in diameter. The D-shaped pipes create enough buoyancy to support
135 tons and are engineered to keep the aquatic houses stable even
in choppy waters or high winds. The floating base supports a three-story
steel structural frame with steel-plate and concrete floors. The
cladding is a prefabricated, low-maintenance skin of made of lightweight
steel plates over the 60-centimeter-deep steel frame with foam insulation.
The interior can be finished in a number of materials; Hertzberger's
studio clad the interior walls in 18 centimeter-thick plywood. Prefab
materials allow the house to be built on a quick four-month construction
The first floor of the prototype currently
bobbing in the waters of De Veersche Poort contains two bedrooms,
a bathroom, and storage space. Upstairs, via a spiral staircase,
is the open living/dining room and a kitchen, all surrounded by
walls of floor-to-ceiling glass. On the third level is a large open
space that can be used as an office or spare bedroom. Each level
has outdoor terraces. An 8-meter-long gangway provides access from
The prototype includes standard (for Holland)
heating and cooling systems, but future options include underfloor
or wall systems; photovoltaics are another energy-saving possibility,
although Franzen explains that the Middelburg villa doesn't have
many high-tech bells and whistles in order to keep
Obviously, it's possible to navigate the Watervilla
to a number of different locations, as much for a change of scenery
as for energy conservation: Hertzberger designed the villa to rotate
90 degrees by means of two steering wheels. The Watervilla can be
moved to capture the best solar orientation, facing the warming
sun in winter and away from the sun in summer to minimize heat gain.
Franzen says he would recommend a small onboard motor if the owner
wanted to change the home's position weekly or even daily.
So far, Watervilla is an information centerconsider
it a floating "model home"but Franzen anticipates
occupancy by the beginning of 2004. Franzen says the studio can't
calculate the exact building cost, given the high engineering expense
involved in getting a prototype off the ground (or into the water),
but he anticipates that the flotation system will be costlier than
earthbound foundations. He estimates future houses will cost between
2,000 and 2,500 euros per square metercurrently $218 to $273
per square foot.