The offered architecture can be classified into three groups based on the roof shape:
Houses with catenary vaults
The earth vaults are built in the form of an inverted chain line, a catenary, on 90 cm high bases. The geometry of the catenary line results in a clear room height of 3.70 m with a selected room width of 3.50 m. Houses of the “Hobbit” series have cross vaults, houses of the “Bóveda“ series have parallel vaults interconnected by massive door arches.
Houses with dome
A dome is one of the most demanding structural elements in architecture. The domes in Valle Tucán are built with special acoustic earth blocks, which are produced on site. The dome currently under construction has an interior diameter of 6 m and a room height of 4.90 m. The geometry of the dome follows a structurally optimized curve, which is achieved by a special rotational guide.
Houses with barrel vaults
Here the vaults start in a height of 2.30 m from ring beams, which rest on vertical walls. With a width of 3.60 m, the rooms have an impressive height of 4.10 m. For this type of house, the architect has produced various designs, which are listed below.
Why vault and dome structures? is a frequent question from visitors why we build these massive vault and dome structures. These structures are ideal for tropical and subtropical climates providing an easy natural ventilation. Furthermore, they allow to cover spaces without steel reinforces concrete elements by using handmade earth blocks from local clayey soil. Only the massive vaults made of earth blocks in combination with the green roofs provide a good thermal and acoustical insulation for the interior. The high ceilings and an optimal cross-ventilation at night guarantee a pleasant indoor climate even in the subtropical midsummer of Paraguay. However, since the question of a comfortable indoor climate is to some degree subjective, we have provided connections for air conditioning in each bedroom.
Why thick earth walls? The normal house walls in Paraguay are built of hollow bricks which have a very poor thermal and acoustic insulation. The 35 to 40 cm thick massive earth walls of the houses in Valle Tucán provide a much better insulation and a much longer life span. A further advantage of the building material earth is that it regulates humidity, it absorbs moisture when the humidity in the room rises above 50% and releases it again when the air is dry. The main component of the earth blocks used is a red clayey soil from a mining site about 2 km away. The earth is mixed with some parts of chippings and coarse sand to get the right properties. The blocks are handmade on site and then dry in the open air, which does not require any additional energy input. The proof that durable buildings can be built with this material is centuries old, even here in Paraguay the walls of old colonial houses consist of nothing else but air-dried earth blocks.