The construction system of Casa Tierra was largely carried out using Pressed Earth Blocks (PEB) made from soil extracted from a surrounding lot. This system was selected because of its wide range of desirable qualities, in addition to an aesthetically pleasing look. Being cost and energy efficient, fire and pest resistant, virtually soundproof, durable, and structurally sound, its suitability was starkly obvious.
PEB provides complete architectural freedom and is made from non-toxic, readily available, natural raw materials. Compared to other systems, it is more flexible and does not affect the width of the walls. The soil was pressed with 3% of concrete and 7% of lime, with the remaining 90% of the material, necessary for construction, extracted directly on-site. In order to accommodate this demand for earth, a basement was incorporated into the design.
The PEB blocks will be distributed across the project’s foundations, being absorbed into 3 different sites across the perimeter. Generating box walls, with either a solid or hollow interior, a variety of devices can be drawn from this simple feature. Either stowing necessary infrastructure, or otherwise allowing a lattice of light to infiltrate softly into the house’s interior; the effect will be especially beautiful to behold during sunrise and sunset.
A team of specialised mechatronic engineers studied the temperature of the lot by drilling devices at different depths; this allowed them to determine the best constant temperature. The results found that taken at a depth of 4m below surface a constant temperature of 17° Celsius was found. Employing this information, 200 linear meters of pipes were fitted, at the appropriate level, for a heat interchange system to maintain the temperature of the house; another example of energy-saving systems being beneficially exploited.
Taking advantage of the characteristically sunny weather of Mexico City, solar collectors will be invested, helping to heat all 100% of the water necessary for daily activities. Further relaxing the drain of electricity is a centralized lighting system, controlling a series of low voltage lamps throughout. Also, photovoltaic panels will be used to reduce the energy consumption, with the predicted result of causing a 30% drop compared to average household usage, for a property of this size. Again, as with water, 100% of the day-to-day demands will be met.
Isolated walls and ceilings will increase the maintenance of the indoors temperature of the house the whole year long. A green rooftop will also be incorporated to increase the isolation and provide fresh clean oxygen into the house. The rooftop is also part of the exterior design of the house and the highlight of this outside concept.