Usalama Classroom Project is underway!

On the morning of June 7th, 2010, EWB-NY Usalama Project team members Charles Newman and Matt Sisul arrived at the Usalama Primary School to commence work on the implementation of four new classrooms. Though this post is coming three weeks after the fact, I thought it would be good to walk the reader through the project thus far. PS All photos are available HERE and HERE.

This post is a first look at the classroom construction from June 7th through June 28th, filling the reader in on the what's happened so far, sort of the greatest hits, and I'll be following this post with a second one, one that is a more detailed look at some of the intricacies and issues surrounding our role as resident architects/engineers, project managers and construction managers.

Classroom Construction: This section will cover the following construction activities: Site Selection, Excavations, Foundations, Floorslab prep work, Floor Slabs, and the start of the Masonry Walls.

Site Selection, June 7th, 2010

Charles and I arrive on the site to the warm welcome of Jackson, the school superintendent and village chairman, Mr. Katolo, the school principal, Charles Wambua, the deputy principal, Faustin, a teacher and the head librarian, and Priscilla a teacher.

Though we were itching to get started with excavation, we first had to present to the school our plans and get feedback before commencing. The main response to our plans, besides, “looks great,” and “yes! let’s get started,” was a request to reorient one of the classroom sets, from between the admin block and entrance south to between the 6 pack of classrooms and the library.

Excavation, June 8th and 9th, 2010

Day 1 of excavation consisted of clearing the sites and etching the edges of the floorslab into the soil. Day 2 involved excavation of 12 to 18 inches of organic and inorganic soil. Excavation was undertaken by parents of the students. The parents will again become a major contributor to the work of the project. The other main laborers are those skilled laborers, the “fundi” or masons and their assistants (mwanafunzi).

Foundations, June 10th through June 15th, 2010

Prior to pouring the foundations, we had to set the hardcore, essential large chunks of volcanic stone quarried in the region. It took a day to get the right levels, with masons hammering the stones into oblivion while Charles or I check the elevations with the construction level. We also spent time prepping the reinforcing steel (Y10 twisted), cut them to length and bent appropriately. A major change from the library project is the inclusion of vertical reinforcing in the buttresses. It requires reinforcing steel (chuma) to extend out of the foundation, and thus must be set in place with wood formwork in order to ensure the proper location once the concrete has set.

Friday, June 11th was the first day for setting of the concrete footing and we selected the western most classroom to be our first site. The process had some kinks, but all in all, it went rather smoothly, having the experience of a lot of the practices from the library construction the previous year. Saturday we poured the adjacent classroom, getting better at the process, so that on Monday we were able to pour both classrooms at once.

A note on naming conventions: we have named the site next to the library “Simba” and the site next to the admin “Tembo”. Simba is Kiswahili for Lion and tembo means elephant. It was a natural development, as we were referring to the classes as either the east or west set or north or south set. So E is for elephant, S is for Simba, Tembo is sorta right there in the middle of campus while Simba is sitting off on the side, waiting to pounce. I guess it’s one of those things that just makes more sense when you’re there!

Floor Slab prep work, June 15th through June 19th, 2010

We hit some of our first delays in the time between the foundation concrete and pouring the floorslabs. A lot of work had to go into setting up the floorslabs. First, one or two courses of stone masonry would have to be placed along the center of the foundation, as the stones end up being the forms for the slab. Some of the earthwork had to be cleared and hardcore placed and blinded (covered with a thin layer of cement/mortar/concrete to eliminate the gaps between the rocks). One problem included coming up with the right elevations for top of soil and top of hardcore while ensuring a 4” thick concrete slab, and a top of slab that lined up perfectly with the top of the stone. What made this process difficult was a delay in the delivery of the stones! We were trying to set the right heights of everything, but had no way of knowing just how high the top of slab would end up being. So after a couple days of clearing, setting the hardcore, resetting, smashing hardcore with sledgehammers, etc, we finally got the stone delivered, and the masons were able to lay the stone in 2 days.

However, this did provide an excellent opportunity to introduce the tube-level, a simple device for determining relative heights, that the masons could use themselves and thus eliminate for me the onerous task of using the construction level to determine elevation.

Floor Slabs, June 21st through June 23rd, 2010

Going into the floorslabs, we knew that this would likely be the most difficult part of construction. It requires the mixing of a considerable amount of concrete ( 30 to 35 bags per floorslab, in a 1:3:3 cement:sand:gravel unorthodox, but resulting from a supply deficiency in gravel) approx. 300 cu ft total, all mixed by shovel, and placed by the masons. We also used welded wire mesh in the middle of a slab to limit those pesky cracks that often result in concrete. We were only able to blind the first classroom, Simba low (Simba is on a slope, so there is Simba high and Simba low). We did our best to be as efficient as possible, but it still meant long days and a lot of stress. The parents, split into 4 groups and each assigned a classroom, were gracious enough to volunteer their time and energy collecting the water and mixing the concrete.

Masonry Walls, June 24th through time of writing (June 28th), 2010

Masonry walls started immediately following the floorslab. The only major surprise was some of the vertical reinforcing was of a smaller diameter than what was meant to be purchased! The masons continue, we now have Avi Guter joining Charles and I in the field, and we will keep you posted on future work!