Build & Test Prep
Table of Contents
Team Vision for Build & Test Prep PhaseOur original plan for the phase is to:
- Continue concrete mixing to decide on best mix based on DOE
- Start building manufacturing machine
We managed to get the lab for concrete mixing at a time that best suited us, and the manufacturing machine is well on its way. An extra task that we also completed was we redesigned the attachment method based on the feedback from Nicaraguan engineers.
Trip to NicaraguaOne of our team members went to Nicaragua over the Winter break to learn more about 4Walls and the housing projects that are going on over there. What follows is a summary that she put together to sum up her experiences there.
Summary of a Trip to Nicaragua over Intersession by Jennifer Kane
- Jan 7 through Jan 19 I was able to visit various cities in Nicaragua including El Sauce, where 4Walls is based. In addition to various tourist activities, I participated in the build of two separate 4Walls houses. There were two others being built at the same time by volunteers who were in El Sauce at the time.
- Some of the activities that I participated in is building the foundation of the four brick walls, mixing the cement for mortar, transporting the bricks by hand and laying them for each of the walls, and cutting wire and bending metal to create rebar beams for the supports.
- Another opportunity I was exposed to is touring a brick maker’s business. I was able to see how “manufacturing” works in El Sauce so we can compare our proposed manufacturing methods to an existing business.
- I spoke with several engineers who live in Nicaragua, learning what materials are easily available and which are more expensive, how transportation of material works, and what primary problems exist with the current roof structure.
- Through visiting hardware stores I was able to see what materials are generally stocked there and the normal prices for the materials used on the roof, along with which materials would have to be specially ordered (and are therefore more expensive)
- An engineer who lived in Nicaragua was promoting a lightweight concrete tile that contains volcanic ash (in place of our biochar) that had a remarkably similar design to our proposal
- I presented our last detailed design powerpoint to the engineers and the representatives from 4Walls (translator and all) and received useful feedback. They approved of our tile design, but they did not approve of the attachment method since it was too complicated for unskilled workers to learn to assemble it, and the heavy reliance on wires is risky in the Nicaraguan environment with the rainy season and humidity that it would be exposed to.
- Other activities included the opportunity for me to interview families who have lived in a 4Walls house for at least a year. These families have the zinc roofs and complain a lot about the noise and the rain, especially with holes that appear to be from nails and reused zinc sheets
Final Tile Design UpdateGiven the feedback that we obtained from the engineers in Nicaragua, we decided to review our attachment method. What we decided on is a tile with - instead of one hole on each flat - one hole on one flat and a nub on the other flat. The way it works is the nub would 'hook' onto the support it is resting on, then a wire will be inserted through the hole, wrapped around the support and then twisted to further secure the tile.
Here are some pictures of the redesigned tile: