Earthquake resistant buildings
How improved building technology can save homes
Practical Action has been helping communities in vulnerable areas to create earthquake resistant buildings for over 25 years.
Where possible we use traditional technologies that can be easily replicated in neighbouring communities, or cheaper alternatives to conventional technologies that still offer protection in the event of an earthquake.
A few simple changes can turn a structurally unsound home into one that can withstand another earthquake.
For example, masons can add cement to their usual mud mortar, and wall binds give buildings added structural integrity.
Practical Action work with local communities to develop solutions most appropriate to their conditions and risks.
In Nepal, we are training masons to give them the skills to build earthquake resilient homes.
Eight schools and 1,300 private houses had been built in Kaski district using new building codes supported by Practical Action. They successfully withstood the earthquakes that struck Nepal in April 2015.
Almost 10,000 people in Nepal have benefited from a project to increase the safety of buildings in the event of an earthquake.
Eight schools were retro-fitted with innovative fibre-glass reinforcements, which are cheaper than conventional iron supports for bracing walls, requiring less time and effort to install, and the technology was included in a further three new-builds.
Additionally, 1,300 private houses have been built following new building codes supported by Practical Action, which successfully withstood the earthquakes that struck Nepal in April 2015.
Following a devastating earthquake in the Alto Mayo region of Peru in 1990 Practical Action became involved in a major reconstruction project to create earthquake resistant buildings using 'improved quincha' – a timber and lattice frame design with an earth infill – based on traditional technologies.
Demonstration buildings were constructed to convince local people of the benefits, and community groups were then engaged to participate in building their own homes and centres and to spread the technology.
During a second quake the following year the improved quincha housing stood up well while others collapsed. The technology has since been used in several thousand houses in the area, and has now been adopted by the mainstream building trade.
Earthquake-resistant buildings were built in Tacna, Southern Peru after an earthquake in 2001. The houses in Tacna are a further development on 'the improved quincha' designs used in Alto Mayo.
Improving the traditional quincha house
In the Grau and San Martín regions of northern Peru over two million people are vulnerable to disasters including those caused by floods, landslides and earthquakes. To alleviate this problem Practical Action introduced an improved building technology that it successfully employed in the Alto Mayo region of Peru called quincha mejorada.
Traditional quincha building technology results in a flexible structure with an inherent earthquake resistance. It has been used in parts of Peru for many centuries.
Traditionally, a quincha house would have a round pole set directly in the ground; infilled with smaller wooden poles and interwoven to form a matrix, which is then plastered with one or more layers of earth.
In May 1990 an earthquake struck the relatively isolated Alto Mayo region of northern Peru. It destroyed 3,000 houses. In the town of Soritor 90% of the houses were damaged or destroyed.
Practical Action worked closely with builders, householders and community organisations in Alto Mayo to introduce improved, earthquake resistant building technology - quincha mejorada.
Improved quincha had the following characteristics over and above traditional quincha:-
- Concrete foundations for greater stability.
- Wooden columns treated with tar or pitch to protect against humidity, concreted into the ground with nails embedded in the wood at the base to give extra anchorage.
- Using concrete wall bases to prevent humidity affecting the wood and the canes in the walls.
- Careful jointing between columns and beams to improve structural integrity.
- Canes woven in a vertical fashion to provide greater stability.
- Lightweight metal sheet roofing to reduce danger of falling tiles.
- Nailing roofing material to roof beams; tying of beams and columns with roof wires.
- Incorporating roof eaves of sufficient width to ensure protection of walls from heavy rains.
In April 1991 a second tremor hit the region damaging a further 9,600 homes.
The 70 improved quincha houses that had been built since May withstood the tremor so well that a further 4,000 houses were built together with several schools and community centres.
Today, knowledge of the design and building skills are so widespread in the local communities that Practical Action has been able to move on to new work.
Your money has been helping people in Nepal.
Thanks to your generous donations, Practical Action has helped provide shelter kits, food and water, sanitation facilities and access to electricity.
But there is still a long way to go. We are continuing to work across the region to help families recover from the disaster.
Please support our Build Back Better appeal so we can build earthquake-proof homes, install water and energy systems and restore people’s livelihoods so they can continue to earn money and provide for their families.