From yesterday’s www.businessmirror.com written by Jonathan L. Mayuga:
CORON, Palawan—Eco-friendly earthbag homes for Supertyphoon Yolanda survivors will soon rise in Barangay Lajala, one of the coastal barangays devastated by the super typhoon in this island municipality last year.
Mayor Carla “Fems” Reyes said the island municipality is planning to construct 300 earthbag homes for those who remain homeless after Yolanda triggered a storm surge that swept away thousands of houses along coastal towns in Central Philippines.
The earthbag homes, with a floor area of 24 square meter, will have one bedroom, one comfort room and a concrete floor, according to a plan approved by the local government of Coron.
Instead of ordinary hollow blocks, a mixture of cement and soil—one part cement and seven parts soil—was used to make bricks that would be used for the walls of the house. For the roofs, doors and windows, bamboo poles or kawayan and nipa will be used.
One brick-like earthbag has a length of 600 mm, a height of 300 mm and thickness of 150 mm. Each earthbag weighs approximately 30 kilos. Durability tests conducted on the dry earthbags indicated it could withstand a pressure of 7,000 psi, almost two times durable than an ordinary hollow block made of sand and cement. The estimated construction cost of a unit is P150,000. The local government has partnered with the Tamayo Foundation for the project.
“We are proud of developing earthbag homes. The walls are durable, resistant to fire and could withstand strong typhoons and earthquakes. And they are affordable,” Reyes said.
About 90 percent of the houses in Barangay Lajala were completely destroyed while the other 10 percent were partly damaged. There are 1,300 families living in the barangay; almost all of them depend on fishing as source of income and livelihood. Because the fishing boats in the barangay were also destroyed, many of the residents are unable to fish and earn money to rebuild their homes.
Six months after Yolanda, only about 10 fishermen are able to fish again while the rest have to rely on income as operator of tourist boats or tour guides, said Barangay Lajala Chairman Allan Mundia. Andy Noda, 27, said his nipa hut was among the close to 1,000 houses destroyed by Yolanda. He said because he also lost his fishing boat, he is unable to earn for the construction of a new nipa hut that would normally cost around P40,000. “My family and I are living with my brother’s family now. If that earthbag house will be given to us, we will accept it, thankful that we will have a home of our own again. It looks strong and more durable than nipa hut. Hopefully, it will not collapse when another strong typhoon hits us,” he said.
Leonilo Serabia, a construction supervisor who worked on a model unit of the earthbag home, said each unit would require 700 earthbags. “The earthbags are tough. It’s cool inside and it is resistant to strong winds. It is easier and faster to build with earthbags,” he said.
Earthbag construction has been proven effective in some countries. It costs less because the materials used are readily available and free, except for cement. Earthbag construction is a natural-building technique that evolved from military-bunker construction techniques and temporary flood-control dike building methods.
Serabia said the earthbag model unit was constructed within a month. The walls are built gradually by placing the earthbags one on top of the other. A barbed wire is placed horizontally in every layer to stabilize the walls. It is then reinforced by placing corrugated steel vertically to keep the earthbags together and the walls intact. The first 24 units of the earthbag homes will be constructed within the next six months while the rest will be constructed as soon as materials for the construction becomes available.
Earthbag construction is labor intensive because it requires hauling of soil and mixing it with cement in preparation for molding. Molding the brick-like earthbags takes several days before they are ready for construction. Some of the residents who will receive earthbag homes have been tapped for work and receive P375 per day plus overtime pay. The soil being is ordinary soil found in the barangay while the bamboos and nipa are locally sourced. The mayor said the development of earthbag homes are ideal for technology-transfer purposes as alternative to the traditional nipa hut or bahay kubo homes in rural areas.
Are you still building Earth Bag homes in Coron, Philippines? If so, I would like to ferry up there to help out. Please contact me with more information if you could use a volunteer. tn101112@yahoo.com
No, I was just investigating the situation while traveling through. It’s well worth the trip. For one, it’s a tropical tourist paradise that’s very popular with tourists. The amazing village that’s being built is just a short ride across the bay. The boats leave next to the best restaurant in town (at that time). You can track down a guide and translator for $20 or so. The ‘airport’ is like a giant cow pasture.
Hi, I’m interested in finding out what bags are used here, the gusseted earth-bags seem to create a more uniform and flat surface, and patterned wall, as opposed to bags with rounded edges. Do they use a mold to fill the bags or are the bags designed to fill out in a rectangular shape? If so I would appreciate any info on where to purchase these particular bags, or instructions on how to make them this way.
They bought custom ordered bags. Sorry, I don’t know the name of their supplier.
They make and tamp the bags in a wood form on the ground then lift into place. It’s not the most efficient method, but the final result is perfectly straight, flat walls.
You can sew your own gusseted bags with a handheld sewing machine like this: https://naturalbuildingblog.siterubix.com/sewing-gusseted-earthbags/
You could make the gusseted bags on the ground and fill the bags on the wall on top of earthbag sliders. This would take less labor and still create excellent results.
Hi Dr. Geiger and Kelly,
Eric Leach and I emailed with you a few month back and since then have finished one earthbag house in northern Leyte. I’ll be traveling there later this week. There are rumors that some business people in the Philippines are investing a lot of money in engineering earthbag designs to popularize it and using it for residential buildings. We are working with the Stargrass Coalition to build 250 earthbag houses in Leyte and Samar by Nov. 2015. I want to translate and print a very simple earthbag building guide for local people with lots of pictures. What would you recommend considering your global experience? I don’t want to have to reinvent the wheel. I’ve purchased both of your books and I don’t want to have to rewrite them for the local context if I can avoid that. :)
Great news. Thanks for writing. I’ll send you can email soon.
There are other advantages to filling and tamping earthbags directly on the walls.
– It’s easier to keep each course level as you build. It’s not difficult to keep each course within 1/4″ or 6mm of level on small homes like this. Simply tape 1m spirit level to a long, straight board and move it around to check level.
– The walls will be more stable as you build. Pre-dried earthbags stacked on top of each other will be a little wobbly because they’re not perfectly flat. Obviously if you’re walking and working on top of the wall then you want stable walls.
-They might be using scaffolding. Scaffolding is not needed if the bags are filled and tamped on the walls. One or two ladders will suffice.
– You can tamp the interior and exterior wall surfaces to reduce plaster work. Don’t try to get them perfectly flat. Mostly tamp the high spots to make the walls straighter.
– Rebar pins will add a lot of extra strength. You can drive 1/2″ rebar pins through freshly tamped earthbags. I highly recommend using rebar like this in disaster prone areas. Corners, doorways and windows are most important to reinforce.
I would love to learn more about this project. Unfortunately, I couldn’t find anything on the Tamayo Foundation.
The photo is small and low resolution, and few construction details are given but I’ll offer a few comments. At first I thought they are ramming the earthbags in a form to make them uniform in size. Closer examination shows the earthbags are irregular, so forms are not being used. This means there will be irregular gaps between bags. It’s far stronger to tamp the bags on the wall so they mold themselves around each other and create some interlocking. This also embeds the barbed wire in the bags and soil.
It’s more efficient to build the earthbags directly on the wall. It takes extra work to make the earthbags on the ground, dry them and then lift and position them on the wall. It’s easier to lift small buckets of soil up on the wall than to lift heavy earthbags.
The method they’re using will create excessive gaps that require extra plaster and labor. A good plasterer can fill the gaps and still create a very strong wall. However, well proven standard earthbag building methods are stronger, faster and easier. Here’s one free step-by-step Instructable:
http://www.instructables.com/id/Step-by-Step-Earthbag-Building/
I don’t understand the part about the corrugated steel. Is it used as temporary bracing or permanent siding?
150,000P = $3,428
Please contact me if you have more information on this project.
Owen Geiger at naturalhouses [AT] gmail.com