How to Make Adobe Bricks

The ingredients that are used to make adobe bricks couldn't be more simple: soil and water. It's cheap and can be very durable in dry climates. The only trick is making sure you have the right kind of soil.

Difficulty:

Moderately Challenging

Instructions

Things You'll Need

• Soil
• Glass jar with lid
• Water
• Something to mix the adobe in like a pit or wheelbarrow
• Shovel
• Brick forms

Test the Soil

1. Fill a glass jar about 2/3 full with the soil you plan to use.

2. Add water until the jar is full and put on the lid.

3. Shake the jar for two full minutes.

4. Let the jar sit overnight.

5. Examine the jar the next morning. The soil will have separated into bands of sand on the bottom and clay on the top. You want the ratio of sand to clay to be roughly 70 percent sand to 30 percent clay. The sand can be less, but you want it above 50 percent.

Prepare to Make Adobe Bricks

1. Clear an area for the bricks to dry. Keep in mind that it can take a couple of weeks for them to dry and you want them protected from the rain.

2. Figure out where you're going to mix your adobe. Small amounts can be done in a wheelbarrow. You can also dig a big pit or build a pit by making a rectangular box of cinder blocks and covering it with a tarp. You can also rent a cement mixer if it's a larger project.

3. Make forms for the bricks. The traditional size is 4 by 10 by 14 inches and this is made with 2 by 4 studs nailed into a ladder like shape.

Make Adobe Bricks

1. Shovel your soil into the mixing place you have prepared. Add sand or clay if necessary.

2. Add water to the soil. This is not an exact science. You're basically making mud. You want it to be firm and able to hold its shape and not too watery.

3. Mix the adobe thoroughly. You want it to be uniform. You can use a shovel or hoe or take your shoes off and stomp on it.

4. Take adobe with your shovel or hand and put it in the brick forms. Be sure to fill in the corners and press it down so it's all filled. Smooth it off with the shovel, by hand or with a piece of wood.

5. Let the bricks dry in the forms for at least 20 minutes.

6. Remove the forms and let the bricks sit flat as they are for about three days.

7. Place the bricks on their edges.

8. Allow the bricks to dry thoroughly. This can take a week or more depending on the weather and your soil.

Tips & Warnings

• You can buy sand or clay to add to your soil to change the ratio to where it should be. This will take some trial and error.

• You can also buy sand and clay and mix them together in a rough 70/30 ratio and use this to make adobe bricks.

• You can test your soil by making a test brick. Make a small batch of adobe and make a brick. Give it a couple of weeks to dry. If your test brick cracks or crumbles or falls apart your soil won't make good adobe bricks.

• It takes a lot of soil to make enough bricks to make even a small wall. Be sure there's plenty around.

• You can make adobe bricks any size you like. Smaller ones are easier to handle and dry more quickly. Larger ones will make putting an adobe wall together a bit faster.

• You can buy brick forms used to make cement bricks instead of building your own forms.

• Some people add straw to the adobe while mixing it. If you do this, you want your adobe to be about 10 percent straw.

• The bricks are dry when they're a uniform light color.

• It can take a few tries before you figure out your soil, how much water to add to it and how long to let it dry. You might want to make a series of test bricks before you start a big project.

• Protect the bricks from the rain while drying.

Resources

• Here's a website about making adobe bricks including finding the right kind of soil to use.