Light and air
Thermal chimney and duct
housingschoolofficebathroomkitchen
A vertical duct that draws air out of the building at the top. The thermal chimney is heated by the sun so that the draft is stronger.
What it solves
It ventilates on hot, windless days, when cross ventilation is not enough. Hot air rises and leaves while cooler air enters through low openings.
Today
Take it above the roof, with the outlet downwind and a dark or glazed face toward the sun. Make sure low air inlets are the same size or larger.
Common mistake
Building the outlet without low air inlets, so that the duct has nothing to draw.
Tomorrow
In heat waves a well-designed thermal chimney moves air without electricity, even when the grid fails. It can be combined with buried ducts that temper the air before it enters.
Fact The greater the height of the duct and the temperature difference, the stronger the draft.
Where it comes from
- 1Persia and Rome Western Asia and Europe, of diffuse origin, centuries ago
They used vertical ducts to move air by temperature difference. - 2Bioclimatic architecture Garston, United Kingdom, contemporary period
An office building with five solar chimneys sought to work without air conditioning.
Masters
- Charles Correa Tube House, Ahmedabad, India, 1962
He designs a narrow house whose sloping section makes hot air rise and leave through an opening at the top. He teaches how to ventilate without machines through the simple draft of air in a hot climate.
Appears in the routes
See also
Also in Light and air
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.