15-21 January 2016 #791

Alternative post quake housing

Rebuilding homes that are safer, environmentally friendlier -- and cheaper
Sahina Shrestha

More than 600,000 buildings were destroyed during the earthquake of April, 2015. Nine months later the biggest challenge is still to rebuild the houses.  As survivors brave the winter and snow, many worry they will end up with the same unsafe houses rebuilt from salvaged material that will once again put their lives at risk.

Nripal Adhikary of the group, Abari which promotes safe and environmentally sustainable designs says safety doesn’t have to be costly. Part of the solution is to rebuild low-cost earthquake-resilient homes using quality locally available materials like bamboo and rammed earth. 

“The benefit of using bamboo is that once treated it is durable, as strong as steel, but flexible. Rammed earth walls are extremely strong and last a long time,” said Adhikary, showing us an under-construction building for Madan Puraskar Pustakalaya in Patan.

REBUILDING BETTER: Nripal Adhikary of the alternative housing group, Abari, (above) explaining the techniques used at the site of a bamboo and rammed-earth structure that is replacing the building of Madan Puraskar Pustakalaya in Patan (below) that was badly damaged in the earthquake.

PICS: YU WEI LIEW

Padma Sundar Joshi of UN-HABITAT agrees that locally available materials will be cost-effective because of their durability and safety. Rammed earth is a soil-based wall system that is dense, solid and stone-like with environmental benefits and low maintenance characteristics. Moreover it uses materials found right under our feet as it is made of compacted gravel, sand and clay with little cement added to it.

“Concrete is not an option for hilly areas. Since they are not easily available transporting them can be expensive,” said Joshi.

Using cheap and environmentally friendly building materials like bamboo and rammed earth in post-earthquake reconstruction can solve the issues of safety, environmental protection and cost.

Hollow concrete blocks and compressed stabilised earth blocks also provide ideal alternatives to bricks. Hollow concrete blocks are highly durable, fire resistant, provide thermal and sound insulation, load bearing capacity, low maintenance, economical and sustainable. 

Compressed earth blocks also use on-site clay or soil which reduces cost and increases efficiency all the while being environmentally friendly. 

Joshi suggests using locally available materials like straw for construction. Straw bales can be used as basis for walls. It provides excellent insulation and is energy efficient. It is easy to make and is cheaper because it is available locally.

After the earthquake as many of the concrete houses in Kathmandu Valley survived and it was the old clay and mortar structures that went down, there is a misconception among people that concrete houses are stronger than the traditional houses

“The only reason many of the houses in Kathmandu survived is because of low intensity of the earthquake here. Look at Chautara for example, a lot of concrete houses went down there,” said Joshi.

He adds that using alternative materials can last a long time provided the timber and bamboo are properly treated. Said Joshi: “It is not like concrete, which is a good thing because that way you can maintain and improve it over time.”

Prefab housing also has its downsides, since most of the material is imported and it doesn’t follow the concept of the 3 R’s: Reduce, reuse, recycle. Building materials like mud, clay and timber on the other hand can easily be reused and disposed of back to the earth.

The biggest challenge that remains for the alternative building materials despite having so many benefits is the mindset of people. Not many want to spend their money on a mud and clay house.

Said Adhikary: “The main challenge about alternative earthquake resistant housing is to change the mindset. We have been able to change the people’s mindset but we are still waiting on the policy makers.”

Read Also:

Homeless in winter, Om Astha Rai

A concrete future, Sonia Awale

Building blocks of rebuilding, Shreesha Nankhwa

Homeless in Nepal, Kunda Dixit