Introduction: Custom Caliche Concrete Block

About: Senior Environmental Design student at CU Boulder

This is a guide to making your own caliche concrete blocks. Caliche has been used for centuries as a readily available cement. Although it is much cheaper and in some places can be sourced from the building site, it remains less commonly used than the various cements that are sold. Using local caliche to make your own concrete blocks is cheap, eco-friendly, and creates a better connection between a building and where it is.

Step 1: Preparations

In places like Texas and New Mexico, caliche can be purchased very cheaply in bulk or excavated at the site. After spreading the material out on a tarp to let it dry out for a few days, it's time to sort it. Using 1/4" wire mesh sift through the material. The larger chunks of caliche can easily be crushed to maximize the usable material. Gloves and safety goggles should be used for the whole process.

Step 2: The Mix

The mix used for this example was:

9% Cement-Lime

55% Sand

36% Caliche

Step 3: Making the Block

Put the mix into a mixer, add water slowly and mix until the texture looks like a thick oatmeal. On a 4 mil plastic sheet Wet the mold and fill it with the mixed caliche concrete, shaking or tapping the mold slightly to fill the corners. Then remove the mold and repeat, wetting the mold every couple of times. Let the blocks cure out of direct sunlight or rain for a few days and after several more days they will be ready to move. Several days after that they should be ready for use.