ADOBE INSULATION COMPOSITES
Summary
This two-week sprint project examined how materials and architectural design can address housing insulation needs in specific climates while respecting cultural and sustainability considerations. Focusing on Quito, Ecuador, and its traditional adobe construction, the project explored sustainable adobe composites for insulation and proposed their architectural integration in response to the city’s daily climate variability.
The Location
Quito is the capital city of Ecuador. It is the second-highest capital city in the world and is located at the equator (latitude zero). Due to its geographical position and high altitude, Quito experiences high daily temperature variability rather than strong seasonal changes: temperatures are relatively high during the day, when solar radiation is intense, and significantly lower at night. As a result, housing design primarily relies on materials and strategies that ensure effective insulation and thermal regulation.
The Experiment
Adobe bricks and earthen facades have been traditionally produced and used in the Ecuadorian Andes for centuries. However, the development of industrial construction materials and techniques has largely displaced adobe-based housing, favoring faster construction methods and materials with higher standardized insulation performance.
In an effort to recover the value of vernacular architecture while leveraging its sustainability potential, different adobe composites were tested. Samples were produced using a standard adobe mixture (mud, straw and water) combined with various sustainable additives. These included tea, feathers, sand dust, coconut shreds, plastic resin, molasses, and soap.
The hypothesis was that these additives would influence, to varying degrees, the heat capacity and thermal conductivity of the adobe bricks, potentially improving their insulation performance.
To test heat capacity, a heating plate was used to heat all samples simultaneously for 25 minutes. The heating rate of each sample was recorded every five minutes using a thermal imaging camera.
To evaluate thermal conductivity, a hot box constructed from foam insulation was used. A light bulb served as the heat source, heating the samples for 15 minutes. Surface temperatures were then recorded with a thermal imaging camera every five minutes over a 30-minute period.
(Left) Adobe-composite samples and (right) composite additives.
(Top) Experiment set up: adobe-composite samples on heating plate, and (bottom) thermal imaging captures.
(Top) Experiment set up: adobe-composite samples in hot box, and (bottom) thermal imaging captures.
The Results
The data obtained during testing are illustrated in the following graphs, showing the comparative heat capacity and thermal conductivity of each sample.
Overall, the adobe composite containing plastic resin demonstrated the most promising insulation performance. This sample exhibited the highest heat capacity and the lowest thermal conductivity, with conductivity values similar to those of the molasses-adobe composite. These findings suggest potential applications for recycled plastic resin in climate-responsive building design.
Heting/cooling curve of adobe-composite samples
Thermal conductivity of adobe-composite samples
The Design
The high daytime temperatures of the target location support heat absorption by the adobe composites; however, a mechanism is needed to enhance air circulation and indoor heating. Therefore, the adobe-composite bricks are integrated into a passive heating system, specifically a Trombe wall.
The system consists of a massive east-facing wall constructed from adobe-composite bricks, with a glass layer installed a few inches in front to create an air gap. Sunlight passes through the glass, is absorbed and stored by the wall, and is later released as temperatures drop. Air circulation is enabled through patterned brick openings that form vents at the top and bottom of the wall.
Adobe-composite bricks design integration through a Trombe-wall
(Left) Illustration of light, heat and cold air tranfer for the proposed design, and (right) brick arrangement pattern for ideal heating.
Minor Archineering, TU Delft
February, 2022
#climate_design
#adobe_bricks
#vernacular_materials
#sustainability