EQ resistant architecture in Himalayas

?EQ resistant architecture in Himalayas

Himalayan towns known for severe earthquakes, locals still honour a millennia-old building style.

?In 1905, a deadly earthquake rocked the landscape of Himachal Pradesh, an Indian state in the western Himalayas. Sturdy-looking concrete constructions toppled like houses of cards. The only surviving structures were in towns where the residents had used an ancient, traditional Himalayan building technique known as kath kuni.

Officers from the Geological Survey of India were amazed by the lack of seismic damage to the castle and other kath kuni homes in the earthquake's radius. "This, at first sight, appeared unnatural on account of the apparently rather top-heavy construction of the houses… until one came to realise the natural resisting power of their timber-bonded walls.

Kath Kuni Design

The design is recognisable by its layered interlocking of deodar wood (a type of Himalayan cedar) with locally sourced stone, without the use of mortar

• Stone gives weight to the structure, resulting in a low centre of gravity, and wood holds the structure together, thanks to its flexibility.
• Doors and windows are built small and have heavy wooden frames to lessen the stress on the openings during an earthquake.
• Buildings have fewer of these openings to help transfer inertial forces to the ground.
• On top of it all, thick slate roofs hold the whole edifice firmly in place

In Corners of any kath kuni building you'll clearly see beams of wood interlocked together. Gaps between these layers are packed with small stones, hay and rubble. This system of intricate interlocking makes kath kuni structures remarkably flexible, allowing walls to move and adjust in case of a seismic event

The technique is perfectly suited to the Himalayas, one of the most seismically active zones in the world

Nature friendly architecture

Kath kuni architecture is also well-adapted to the region's agrarian and communitarian style of living. Generally, the ground?floor?is reserved for livestock. Upper storeys are used as living quarters since they're a lot warmer, thanks to the sunlight and the rising body heat of livestock from below

Kath kuni homes are designed in a way that lets keep cattle loose in the open space on the bottom storey and move them inside at the time of milking or during harsh weather conditions. They are also generally built-in clusters, making it easy to share livestock and storage space