L3P Architekten has completed the Externally United – Internally Atwain Duplex House (low-energy consumption building), 5408 Ennetbaden Aargau, Switzerland 2012. Despite the small block of land (637m2), a generous duplex house has been developed in an architecturally heterogeneous neighbourhood on the south face of Ennetbaden, which, in reference to organisation, takes an interesting and unconventional path
The floor-plan volume is comprised of distorted rectangles. The architects dissected the volume at diverse sites. Besides the resulting attractive remaining volume, each of these dissections is intended to fulfil an additional function:
- The cut in the north of the ground floor allows a north-side access to the house.
- The breach on the ground floor allows access to the garden area which is used by both parties living in the house.
- The cut in the south side of the ground floor presents the party in the lower house with the covered south terrace, which is contained within the main rectangle.
- Both of the volume cuts in the attic provide the party in the upper house with south and north terraces.
The duplex house is not readable from the outside. The main surface are rendered with a horizontal brush with a 6mm render, treated and painted in a subtle green tone. On the contrary, the dissected surfaces are treated with a 0.5mm fine render in a brown colour scheme, thus machining an additional volume cut. The windows are also treated in two colours: the protruding, box-shaped constructions are kept aluminium-coloured externally, while the small-formed windows that are flush with the exterior surface, as well as the shutters, appear in golden tones.
The interior of the two units are intrinsically different. The valley-side unit stretches below from the naturally-lit sleeping area over the ground floor, including the living / dining / kitchen area, up to the upper floor encompassing the bedrooms. The continuous staircase leaning on the fire division wall serves as a connection to the third floor, building a formative element of the interior. The two-storey living area is completed without the usual accessibility, thus gaining power and dynamic. The design of the interior with its exposed cast concrete ceilings, floors and partial walls, as well as the white kitchen with cast concrete exposure gives an archaic impression.
The hillside unit stretches over four floors which are combined through a central core. The common utilities management and workshop is found in the basement. The ground floor with its entry and wardrobe only serves as a collection point to the upper floors with the bedrooms. The formative element here is the access to the overlapping staircase, which changes direction and entry-side with every floor. In the attic storey, the core of the unit is lighted from above with polygonal apertures in the wall and roof. The surrounding living, dining and kitchen area are arranged on the south and north-sided terraces. The view to the south from the timber decking and the intensive roof-greening are breath-taking. For the materialisation a mixture of cast concrete and oak parquet flooring in combination with exposed concrete ceilings and partial walls was chosen.
This duplex house is in true spirit of the expression: externally united – internally atwain.
+ Project facts
Architect: L3P Architects ETH FH SIA AG, Martin Reusser, Boris Egli, Markus Müller, Frank Schäfer, Regensberg Switzerland
Building Constructor: 2 private owners
Building Engineer: Tantanini + Partner AG, Bülach
Structural Engineer: Wichser Akustik & Bauphysik AG, Zürich
Photographer: Sabrina Scheja
Building Time-frame: August 2011 to July 2012
Netto Floor Surface NGF: ca. 210 m2 per house unit incl. side-rooms + 50 m2 Garage and bicycle room (for both units)
Plot Size: 637m2