Project data
Authors Leandra Arcata, California Deployed 2009 Yes No USD 99.28 Cobb constructionCobb oven Download Upload your project too!body.poncho-dark-mode .mw-parser-output .mw-ui-button{background:#303134;border-color:#3c4043;color:#bdc1c6}@media screen and (max-width:500px){.mw-parser-output .button .mw-ui-button{display:block;margin:.5em 0}}

At Cal Poly Humboldt the course Engr 215 allows one the real life experience through service learning. During the Fall semester of 2009, our team, the Muddy Cobbers, worked on a design project for the Campus Center for Appropriate Technology (CCAT). The goal of the project was to implement a solution that would protect and beautify the cob installations at CCAT.

## Background

The Campus Center for Appropriate Technology has two cob installations a bench and an oven. These were both student project built in approximately 2005.

Cob is a type of earthen building material composed of clay, sand, and straw. At CCAT, these cob installations are demonstrations of appropriate building techniques.

## Problem statement and criteria

While cob is a very durable material in some climates, like Humboldt County's, it must be sealed. Weather plays a large role in the degrading of cob and without a proper seal, like a plaster, the cob will not last very long. Since being built, signs of weathering were already apparent in both the bench and oven. Our team was presented with this problem: find a way to protect and beautify the cob installations.

Criteria

The criteria considered for this project were decided upon by our group with help from CCAT's directors. The criteria were then ranked by their importance starting with the most important.

1. Durability: Our solution must be durable enough to preserve the finished product, withstand Humboldt county weather conditions, and resist potential minor vandalism. In their current condition as untreated cob, the bench and oven are not very weather resistant or damage resistant.
2. Aesthetics: Our solution must improve the aesthetic appeal of the bench and the oven in the eyes of the CCAT directors and visitors to CCAT. The aesthetics must be improved in a way that is appropriate and long lasting.
3. Appropriateness: Our solution must use methods, materials and technologies that are as local and sustainable as possible. Both cob installations demonstrate an appropriate sustainable building material and method, our solution should be aligned with this demonstration.
4. Maintainability: Our solution must be maintainable by the CCAT directors and volunteer workforce with reasonable ease.
5. Safety: Our solution must ensure the bench be safe enough to sit on, and the oven safe to cook with. Both installations are currently safe to use so our solution need only maintain the current level of safety if not improve upon it.

## Discussion and next steps

The Muddy Cobbers and CCAT are happy with the finished product. It is good to know that these cob installations will serve a multitude of purposes. For instance, while the bench provides visitors a leisurely place to relax they will also bbe learning about an appropriate building technique.

Our hope for future CCAT directors and volunteers is that these installations will continue to serve their myriad of purposes. We believe that upkeep of the cob installations will allow this to happen for a long time. Below we have provided a quick tutorial on repair:

Bench:

Oven: