Matter and surface
Thermal mass
school office public building hotel housing complex
The capacity of heavy materials such as adobe, stone, brick or concrete to store heat and release it hours later.
What it solves
It flattens the rise and fall of temperature between day and night. It works where days are hot and nights cool, but in the humid coastal tropics it can give back heat at night and keep people awake.
Today
Use mass where the difference between day and night is large, as in highland areas. Protect it from the sun with eaves and shade. On the hot, humid coast prefer light, ventilated and shaded structures.
Common mistake
Filling a coastal building with concrete and block without shade or ventilation, which at night keeps releasing the day’s heat.
Tomorrow
In warm climates a heavy slab can be cooled by day with air conditioning powered by solar panels so it releases coolness at night. Earth walls from the site provide mass with little energy.
Fact An official Australian guide recommends low mass where the difference between day and night is 6 °C or less, medium mass between 6 and 10 °C and high mass above 10 °C.
Where it comes from
- 1Taos Pueblo New Mexico, United States, around the year 1000
The Tiwa build a multi-story complex with very thick adobe walls that is still inhabited. - 2Adobe construction the Americas, Spain and Egypt, for millennia
In climates with hot days and cool nights, thick adobe walls keep releasing heat inward for several hours after sunset.
Masters
- Balkrishna Doshi Sangath, Ahmedabad, India, 1978
He half-buries his studio under vaults covered in white mosaic, with earth mounds and pools that hold back the heat of the sun. He teaches how to use earth, water and shade together in a very hot climate.
See also
Also in Matter and surface
Diagrams and texts by LDB Arquitectura. They are shared under the CC BY 4.0 license, which allows them to be used and adapted with credit to the source.