Guest blog by Ann Senn
Global Village Volunteer
A new appreciation for bricks!
This morning, my husband Mark Ambrosen and I worked at the CEB site making “compressed earth bricks”—a special Habitat Cambodia project. The brick making process is laborious—sand is shoveled into buckets and carried to one of three sifting stations. At the sifting station, the sand is poured a bucket at a time onto a square wooden framed screen where it is scraped back and forth over the screen with paddles to sort out rocks and clumps of clay. Sifted sand is shoveled off the floor back into buckets, then mixed with cement and a little water in a huge basin with a motor driven paddle. After the sand and cement is thoroughly combined, the batch is dumped on the floor and shoveled a bucket at a time into the brick press.
Ann digging sand
Mark at the sand sifting station
Finished bricks sitting to cure
Why compressed earth bricks?
Habitat Cambodia is introducing CEB (compressed earth bricks) instead of traditional fired bricks because the firing process is harmful to the environment. CEB bricks are also very attractive. While the CEB process is a bit more expensive, the brick becomes cost neutral if the brick is left exposed rather than plastered or mudded (as is the custom with most fired brick walls.)
11 large buckets of sand and 1 bag of cement (the amount of water is an art) = 60 bricks,
Our team made 410 bricks after 2.75 hours. It takes about 30 seconds to sift a bucket of sand and the brick machine can press about 4 bricks per minute.
Well, we can attest to the fact that compressed earth bricks are remarkably hard—harder than any bricks I have ever worked with.
After the adventure at the CEB site, we returned to our build site. The afternoon’s task was to pour a cement floor and the first step was to prepare the interior ground. We scraped debris from the walls and proceeded to smash the construction debris inside (broken bricks and rock) to level the interior ground -- the bricks were almost as hard to break up as the natural stone.
Our house team beginning to mix the cement floor
Pouring the floor was an experience. We hauled sand into the house into piles where we added cement and mixed the two materials with a hoe. The piles were then hollowed out like a volcano, filled with water, and then mixed in place. Skilled workers then spread the cement across the floor with long metal bars. Interestingly, they wore rubber gloves but walked through the wet cement with bare feet.
Worker smoothing concrete
Our blue hat, Piset, explained that floors should be dry by tomorrow morning—that seems almost impossible given the humidity here but he certainly knows what he is doing!
Number of Bricks to a house? We didn’t count… but perhaps 2000-2500.
A shoutout to our small but mighty CEB team of 4 US/Canadian volunteers, 3 skilled local brick makers, and the 4 additional recruits that added great energy to the group about an hour into our shift! A shoutout to the great Habitat skilled workers and Twin Cities Habitat team members for their hard labor in the heat.
And, a shoutout to the wonderful Cambodia Habitat homeowners and community members who delivered waters and wrapped cold waters (with love) around our sweaty necks this afternoon.
I will never look at a brick the same way again!
Learn about our upcoming trips in 2018 to the Dominican Republic and Nicaragua.