Earth bag houses save forests

Fewer trees means more disasters
An unusual home construction technique using dirt or sand packed into plastic sacks and stacked - is now being tried out in Rumphi as a way to cut back on bricks and save what's left of the region's forests

Mzuzu, Malawi: At the local brick kiln, a truck laden with logs pulls up and unloads. Soon smoke is billowing, as a new set of bricks bakes inside. Malawi's construction industry relies heavily on bricks and the wood needed to make them is a major reason the country's indigenous forests are fast disappearing.

But an unusual home construction technique using dirt or sand packed into plastic sacks and stacked is now being tried out in Rumphi, in the north of the country, as a way to cut back on bricks and save what's left of the region's forests.

As part of the project, carried out by the Roscher Youth Development Centre with German backing, young people are being given technical and financial help to construct the environmentally friendly houses.

"We have lost a lot of trees and we now still continue losing them, at a chilling rate. Our mountains and hills that had thick forests are now bare except for a few trees and shrubs," said Moir Walita Mkandawire, executive director of the non-profit youth development centre.

That loss of forest has led to more extreme weather and worsening droughts, he said, one reason the remaining trees need to be protected. "The weather we have now is not the same we used to have decades ago," he said.

According to statistics from the Department of Forestry, Malawi annually has been losing about 1.6 per cent to 2.8 per cent of its forests to human activities.

But in February, Ronnnie Chirambo, a tree planting officer with the Department of Forestry, told a local newspaper that the deforestation rate was now down to 1 per cent a year, simply because there were too few trees left to cut down.

As the forests have disappeared, natural disasters - including droughts, cyclones, landslides and floods - have become a regular and costly threat in towns such as Rumphi, located 67 km from Mzuzu, the largest city in Malawi's Northern Region.

Heinrich Wegener of Support Malawi Heidelberg, which has provided technical and financial backing for the housing initiative, said he first heard about ‘earth bag’ homes in 2012 while on a visit to South Africa. He felt the homes would be an ideal solution for Malawi.

"I started to research the various ways to build houses with sandbags instead of bricks. My idea was to try a first earth bag house as a prototype", working with the youth centre in Rumphi, he said.

If such houses catch on, Wegener believes they could become a major contributor to cutting deforestation in Malawi. "Sandbag houses can help because they are cheap and simple to build," he said. "Just fill used plastic or other bags with soil, close them, stack them into walls, leave space for windows and doors, put a roof on top, plaster the walls. That's basically it, and it saves a lot of wood and time."

He said the cost of the houses depends on the size and amenities added, but a small village home without electricity or a toilet should cost around $1,400. Allan Chitete, a civil engineer and the Rumphi director of public works, said he thinks the homes will ultimately become widely used, and not just because they cut the need for wood for construction and for baking bricks.

"The building blocks (sacks filled with earth or sand) have a lot of advantages," he said. "They act like cushions or shock absorbers so that in times of earthquake or floods the structure cannot develop cracks or collapse," he predicted.

The idea of building low-cost structures of sandbags or soil-filled bags has been around for at least a century, and has been used in a range of places, from Africa to South Asia to North America. Perhaps the toughest barrier to expanding use of the homes in Malawi will be winning over people to a dramatic change in the idea of what a house is made of, Wegener admitted. Most homes today are built of brick.

He said the main disadvantage of the earth houses is that hammering a nail into the wall to hang art or portraits can be hugely difficult. Their backers hope the homes may find backing from Malawi's government, which is trying to discourage the use of wood-baked bricks in construction in favour of cement blocks and ‘stabilised soil’ blocks.

Chitete said he will try to sell the idea of more earth bag homes to members of Malawi's Parliament and ward councillors. The youth centre also plans to train more young people in the district in the building technique, and hopes to roll out the initiative to other disaster-prone areas of the country.