Disaster-proofing Bantayan
Resort, Caritas homes use compressed earth blocks stronger than concrete hollow blocks
AFTER typhoon Yolanda hit last Nov. 8, 2013, a local non-government organization (NGO) in Bantayan Island, Cebu decided to make Interlocking Compressed Earth Blocks (ICEB) that can be used by the community in building structures to keep them safe in the next disasters.
Damgo sa Kaugmaon Inc., a registered non-stock and non-profit organization, is the first organization in Bantayan Island to produce ICEBs using local materials.
Damgo head dreamer Allan Monreal said one can save 21 percent on the cost of building structures using ICEBs compared to the concrete hollow blocks (CHB) commonly used in any construction.
Monreal has been staying in Bantayan Island where his family has a resort, Bantayan Island Nature Park and Resort.
Initially, the resort had its Back to Sea project, where it provided a livelihood rehabilitation program to 25 people’s organizations in 25 barangays in the island’s three towns: Santa Fe, Bantayan and Madridejos. Eventually, the project was adopted by the Bantayan Island Association of Hotels, Resorts, Bars and Restaurants, and Damgo sa Kaugmaon (Dream for the Future) was born.
Block making
Damgo sa Kaugmaon with the help of the International Labor Organization (ILO) came up with a social enterprise that produces ICEB, which they locally call Damgo Earth Block.
Monreal said the ILO provided them with three ICEB molding machines, two single molders and a double molder. The ICEBs are made using the resources available within the island.
Unlike CHBs, the ICEBs are made of limestone instead of sand. The limestone comes from a local supplier.
“Dapat 20 percent, kasi nga pagmataas yung clay content (There should only be 20 percent clay content on the limestone. If there is more than that) you have to add more stabilizers or cement. If there is more clay content, it would be prone to shrinkage and expansion. Expansion if it gets wet, shrinkage mainit (if exposed to heat),” Monreal said.
Damgo has 100 workers to make the ICEBs in its facility called Dream Zone in Barangay Kangkaibe in Bantayan town.
Process
Damgo hired people on the island to crack big limestone into pieces. The small pieces are placed into the hammer mill to pulverize the limestone. The pulverized limestone is then placed in the trommel screen to properly sift and separate the particles.
The pulverized limestone is mixed with portland cement, an additive and water to moisten the mixture. Then the mixture is placed in the ICEB molding machines. A molder for one ICEB should have at least 7.5 to 8 kilograms mixture.
The manual molding machine is pressed for two seconds, and then the ICEBs are brought to an adjacent area for curing.
For curing, Monreal said the ICEBs are exposed to the air for one day. After that, they undergo wet curing where these are fully covered with tarpaulin for one week. For the dry curing, the ICEBs are exposed, but the tarpaulins are still placed on top. The curing period lasts up to 28 days.
Damgo produces 2,100 blocks in eight hours with 23 workers. Damgo sells one ICEB for P23.
People think it’s expensive, but actually they can save more because it’s durable, he said.
“Mas gusto nila yung P13 na baybay na hollow blocks na paggunit mo durog kaysa nito na matibay, kasi mahal daw per piraso (They prefer the CHB which costs P13 per piece, but it disintegrates when held).”
Damgo showed that a structure owner using its earth blocks will spend only P2,355.18 a square meter, lower than sea sand CHB’s P2,987.33 a square meter.
A structure with a ninesquare-meter floor area will cost only P21,196.66 using ICEBs compared to P26,885.99 with sea sand CHBs. Steel works for ICEB cost only P692.40 compared to P3,740.10 for the sea sand CHBs.
For structures made of Damgo Earth Block, there is no cost for the formworks, while one spends P4,037.50 for formworks using sea sand CHBs. ICEBs also need less cement than structures made of sea sand CHBs.
Caritas Switzerland
Damgo supplies ICEBs to Caritas Switzerland, which has a house reconstruction project in typhoon Yolanda-hit Madridejos and Kinatarcan Island in Santa Fe. The international NGO targets to build 1,200 houses, 600 each in Madridejos and Kinatarcan.
Architect Jonathan Brigham, technical delegate in the Philippines for Shelter of Caritas Humanitarian Aid Department, said the ICEBs are stronger than the standard CHBs in the island. He said less cement and steel is needed.
“So it’s not only a better product and stronger than CHB, but also reducing the overall course when constructing with ICEBS versus CHBs because we are not using cement when building walls, for example,” Brigham said.
He said they also avoided importing materials needed to produce hollow blocks, which are usually made of sand and gravel.
Brigham also appreciated that Damgo uses the human resources in Bantayan Island to produce the Damgo Earth Blocks. “It’s focused on helping the local communities. We are creating economic opportunities by using ICEBs,” he said.
Disaster-resistant
Caritas spent just P120,000 for each house. According to Caritas Switzerland’s fact sheet, the house has an area of 48 square meters. Half of the structure’s wall is made of ICEBs, the other half of coco lumber and bamboo. For the Caritas housing project, Damgo has been supplying 839 blocks per structure. Aside from considering the budget, Brigham said they made half of the structure with light materials to provide ventilation. The design is based on the traditonal local architecture in northern Cebu.
“It had been designed to resist a level of earthquake. 7.2 magnitude is the earthquake resistance of the design, and the wind speed is up to 200 kph…” he said. “They are durable but also very affordable, so there are lots and lots of advantages of using the ICEBs.”
The houses by Caritas can last up to 20 years, or depending on how well the family cares for the house. The house has a comfort room, bedroom, living room and septic tanks.
Builders
Brigham said the beneficiaries and master trainers, who are also workers from the island, helped Caritas build the houses. He said the master trainers were paid because they are skilled workers that understand good carpentry skills, how to use the ICEBs and house design. They were trained by Caritas and Damgo. Caritas started rebuilding the houses of typhoon survivors in May 2015. They will be completed in July 2017. By the end of July, Brigham said, they will finish 670 houses—500 in Madridejos and 170 in Kinatarcan.
Better house
The Cebu Provincial Rehabilitation, Recovery and Development Plan listed 152,746 families affected when typhoon Yolanda hit northern Cebu, of which 16,290 households needed to be relocated because their houses were within the 40-meter danger zone. Alma Baulita of Barangay Kaongkod
in Madridejos is thankful for the new house provided by Caritas because she believes her family is now safer.
Baulita, 22, previously stayed in her parents’ house with her four siblings, two of whom already have their own family. The house walls were made only of plywood.
“Dako kaayo’ng tabang. Makaginhawa mi, labi na sauna magsardinas mi. Di makahigda og tarong (It’s a big help. Before, we could not lie down properly because we were packed like sardines),” she said.
Baulita’s family moved to their new house last August.
She recalled that, with her husband a seaman, she was left in their new house with their oneyear-old son and three-year-old daughter when heavy rains and strong winds came last month. But Baulita, pregnant with her third child, was never worried.
Marites Illosorio, 30, said when her family’s house was destroyed by Yolanda (Haiyan), her stepfather made a hut. Half of the hut’s roof was made of used galvanized iron sheets, the other half of tarpaulin. During rains, they had to transfer from their bedroom to the other side of the house because water fell from their roof. It was a dilemma for her four-year-old son in kindergarten because he could not study well.
Illosorio’s worries were left behind when they moved to their new house in Sitio Crossing Pantalan in Kaongkod, Madridejos.
According to the Global Shelter Cluster, the minimum compressive strength of an individual CHB is 800 pounds per square inch (psi) based on the existing standards for CHBs and CHB wall construction in the Philippines.
In a test report issued by the Department of Public Works and Highways Terms Concrete Testing, Damgo’s ICEB, which is cured for 28 days, has a compressive strength of 981 psi. The ICEB was tested last July 9, 2016.
Advantages
Concrete earth blocks are not new in the field of construction. However, Monreal said, what differentiates Damgo’s ICEB from the others is its interlocking feature.
“There are compressed earth blocks that are like bricks only because they are not interlocking. Kailangan mo pa rin ng semento. Ito patong-patong. Kaya nga kung gagamitin ito, kahit wala nang
kabilya (You’d still need cement. The ICEBs can be used even without the steel works),” he said.
Damgo’s ICEBs are also environment-friendly. Monreal said they have less carbon footprint because they use a manual ICEB molding machine.
“Our carbon footprint here is only for the engine for the pulverizer, but there is none for the processing itself, unlike sa paggawa ng (in the making of) fired bricks,” he said.
Good for resort
Aside from Caritas, Bantayan Island Nature Park and Resort is now slowly upgrading its cottages using Damgo Earth Blocks.
Jun Pacheco, owner of the resort, said they now have three structures, composed of five rooms, made of ICEBs. These include two duplex cottages and a single one.
The resort has 26 rooms.
Pacheco recalled that some of their cottages, which were made of light materials, were damaged when typhoon Yolanda hit.
“Lig-on siya, unya naa baya ta sa typhoon area (I’m using it because it’s sturdy, especially since we’re in a typhoon area). Second, I’m using that because of the anay (termites). And it’s cool (inside the cottage made of ICEB),” he said.
Damgo uses limestone, which makes the ICEB cooler than the CHBs made of sand.
For the rehabilitation of the structure, Pacheco spent less than P80,000 for a 40-square-meter cottage. “Mas gamay gyud ang gasto ana. Kung hollow blocks ang gamiton, di ni kaayo lig-on (It really costs less. If CHBs were used, the structure would not be that strong),” he said.
The resort also expects lower power consumption, especially in the use of air conditioning in every cottage, for the structure made of ICEB is cooler.
Pacheco, one of the founders of Damgo, said he now has more sound structures than before.
Humanitarian work
ICEB making enables Damgo to continue its humanitarian and development work in the island. The local organization pays its workers the minimum wage and provides them with benefits like Social Security System, Philhealth and personal accident insurance.
“You treat your people right, good working conditions, decent work, decent wage. ... Minimum wage kami, SSS, profit sharing, environment responsible. Make sure you give back to mother nature,” said Monreal.
Damgo now has another social enterprise, the Marine Products Processing Center, built using ICEBs. This center helps the people in the island earn by producing and processing marine products.
Jessica Seas, 24, a resident of Gawad Kalinga Village in Barangay Ticad in Bantayan proper, started working in the Dream Zone by cracking large limestone into pieces. Then she became a mover, placing the ICEBs in the curing area. Now seven months pregnant with twins, she is the time keeper.
Seas said it was Damgo officials who helped her family when her mother was brought to the hospital due to diabetes last September. Her mother is now doing very well.
From a limestone crusher, Ramil Gila, 29, of Barangay Sungko
is now the supervisor of the Dream Zone. “Daghan na ko og napasud nga taw, mga silingan namo ug
mga relatives, mga almost 20 (I have helped about 20 relatives and neighbors to get jobs),” Gila said.
Previously, Gila worked in a poultry in the morning and fished at night to sustain his family’s needs. Since working for Damgo, he has been able to slowly repair his house.
So Damgo can continue its operations, Gila and Seas try to encourage the barangay officials and their friends to use ICEBs.
Promoting ICEBs
In Caritas, Brigham said, they promote ICEBs, especially in Bantayan, after this was hit by Yolanda. He said the Damgo Earth Block is ideal for use on the island.
“We share information, and we work with Damgo. We don’t just look at Damgo as a supplier, but it’s a partnership. There are local organizations, so we want to support Damgo as much as we can, and we advocate the use of ICEBs,” he said.
For his part, Pacheco said he tried to encourage other resort owners to use ICEBs, but they have different mindsets.
Madridejos Vice Mayor Salvador Dela Fuente agreed that Damgo Earth Blocks are strong and good for making typhoonresilient houses. The town mayor when Yolanda hit, Dela Fuente said he would like to personally use this type of blocks, especially since it has good thermal insulation properties.
“Ideal man siya kay it’s an earth block. Pero murag sa atong
part, atong obserbahan kay based sa mga engineering design, ang na- use na gud mga hollow blocks,” he said. (Earth blocks are ideal. But we would like to study this first because engineering designs normally use hollow blocks.)
The vice mayor said it needs proper study because he believes earth blocks may be good for use only in bungalow structures and not in multiple-story buildings. He would also like to check the cost of the structures made of this.
Slow adoption
ICEBs are not yet widely adopted in Bantayan Island.
Monreal said he tried to propose this to some government officials and other NGOs and foundations of big firms that helped in building classrooms, but they still preferred to use the traditional construction materials.
He said the classrooms are used by the government as evacuation centers, but still the structures are made of CHBs with low quality.
“Actually di na dapat persuasion, how to enforce. Yun na, kasi eventually magiging problema din
sila ng gobyerno later on,” he said. (Government should enforce, instead of use persuasion to encourage people to use this, because later on, evacuating the people to a better evacuation center will still be the government’s problem.)
Given the opportunity, Monreal will present this to the National Housing Authority officials who are set to provide housing units to the typhoon Yolanda-hit areas.
Damgo officials also tried to go to hardware stores to convince them to sell ICEBs, but they realized that these establishments can earn more selling CHBs.
To encourage others to use the Damgo Earth Blocks, Monreal said he will bring this up during environmental forums. ICEBs can be used for building schools and even two-story structures because of their compressive strength, according to him.
He said ICEBs are used not only to build cheap houses. “It really shouldn’t be categorized as alternative cheap housing material. No, it’s not. It’s supposed to be a climate-resilient and sustainable unit masonry of building blocks.”