Adobe bricks are created from a mixture of sand, silt, and clay, a form of soil, which is then mixed with water and exposed to the sun for drying.
An adobe wall (made of adobe bricks), plastered with naturally the same adobe mixture plaster, necessitates routine upkeep and repair – especially if it’s constantly exposed to the outdoors.
And the good thing is if you decide to plaster or paint over the repaired area, you won’t actually see the bricks, so aesthetics aren’t really important here.
But remember, if the plaster keeps on eroding and reaches an extent where it becomes irreparable, it needs to be replaced immediately. So, it’s good to maintain and preserve the adobe bricks rather than replace an entire adobe wall.
So, how do you exactly repair and preserve the adobe brick walls in your adobe home? Let’s take a closer look at the steps in this helpful guide…
Prepare the Mud
Repairing the adobe walls in your home involves various steps, like fixing the plaster, checking the mortar, and then the bricks themselves.
But to repair the plaster on adobe homes, we will need to get a thick mud plaster.
You can easily mix up some thick adobe plaster (mud) with fairly high clay content and straw, following the recipe that’s used for the bricks.
- Combine soil, water, and sand to make a mixture like mud.
- Incorporate straw, grass, or pine needles into it while stirring the mix.
To prepare the adobe bricks, you need to spoon this concoction into your molds and leave them in direct sunlight for 5-7 days to bake them.
But for our next step, we need only to use the prepared adobe mud mixture without any baking.
Repairing the Plaster
Start by removing any cracked or deteriorated plaster from the adobe wall using a scraper and spray the area you’re going to patch with water until it’s slightly damp.
Coat the damp area with plaster until all of the cracks and depressions are filled out and match the surrounding plaster. Allow this mud layer to dry completely before proceeding.
Repairing the Mortar
Once you have repaired the outer plaster, remove any loose or damaged mortar from the joint between the bricks – extract all of the mortar from joints that are two to three times wider than the depth of a usual mortar joint.
Now start making the fresh adobe mixture, which is used to make bricks; however, make it slightly wetter than the standard recipe. You will also need some dry adobe plaster, so keep some of the mixtures without water
Next, use a spray bottle filled with water to mist over the area around the repair job lightly until it’s dampened but not soaked through.
Fill in gaps with fresh mortar using a trowel and allow it sufficient time to air-dry properly.
After that, use the prepared adobe plaster to cover up repaired areas completely. And if required, apply some dry adobe plaster mix over it for faster drying.
Repairing the Adobe Bricks
If only a small section of your brick has deteriorated, you can scrape it out and patch it with adobe plaster and mortar.
However, if a substantial area is affected, you’ll need to replace a majority of bricks or at least some of them.
To fix this issue, first, scrape out and remove all deteriorated parts (including any good brick that might be necessary to have a stable surface for new materials).
Get the area you’ll patch wet, which will make it easier to work with.
After that, add some mortar to the brick and insert it into the wall. If needed, put more mortar around it, so the patch is even with everything else.
Let the mortar dry, and then plaster over the repaired spot.
Tips and Warnings
Do not replace adobe mortar with lime or cement mortar. Also, do not use regular bricks, concrete blocks, or cinderblocks to replace your adobe bricks.
The wall will most likely crack because these types of mortar and bricks don’t have the same thermal expansion rates as adobe.
Moreover, if you see any crumbling walls or major cracks that can’t be repaired easily, do not try fixing these structural problems on your own.
These should often be replaced and left to professionals.
What’s the Difference Between Adobe and Regular Brick?
The biggest difference between adobe and regular bricks is that the first one is sun-dried, whereas the latter is kiln fired at a very high temperature.
Unlike traditional bricks, adobe is made from clay, straw, and water mixed and formed into blocks or bricks that are dried by the sun.
Because of the sun drying, adobe walls do not need to be fired in a kiln, which greatly reduces the cost of construction. Also, this construction method allows for a more customized design.
Can Adobe Bricks be Painted – Tips and Tricks
The beauty of adobe brick walls is that they can be left unpainted if you like a natural earthen color look.
And if at any time in the future, you desire to change the muddy colors of beige and brown, you can cover the neutral shades of your earthy adobe home by painting.
Fortunately, painting adobe bricks are not so challenging if you keep a few things in mind. These are:
- Applying paint directly to adobe walls is not recommended, as adobe will quickly absorb it.
- To get better results with adobe bricks painting, you must first mix and apply a sealer to them.
- Use different sealers and paints for coating interior and exterior adobe walls because of the changes in weather and temperature affecting the walls.
Sealing Interior Adobe Walls
Tapioca powder (a natural glue) mixed with water works well as a sealer for interior adobe walls.
- In a bowl, mix 1.5 cups of tapioca powder with 1 cup of cold water until combined.
- Then in a pot on the stove, bring 4 liters of water to a boil.
- Add the tapioca mixture to the boiling water and reduce the heat to simmer. Stir continuously until the mixture becomes clear.
- The mixture should be applied on a well-repaired adobe wall with a brush and left to dry overnight.
- Once the sealer is set, you can apply two coats of water-based latex or acrylic paint for interiors.
Sealing Exterior Adobe Brick Walls
Linseed oil is ideal for sealing and protecting exterior adobe bricks from moisture, wind, and extreme temperatures.
You can prepare the sealer by mixing one part of boiled linseed oil with three parts of paint thinner.
- Using a brush and/or sprayer, apply two coats of thinned linseed oil to the already repaired adobe walls. Allow it to dry between coats.
- Once the sealer has been dried and set for at least 24 hours, paint your exterior adobe walls with an oil-based or acrylic paint that is designed for outdoor use.
- When painting exterior adobe bricks, make sure you use weatherproof paints that can withstand extreme temperatures and UV protection.
- Also, ensure to apply two or three coats of paint, allowing it to dry between each coat.
Can You Finish and Make Adobe Bricks Waterproof?
One common myth among many people wonder is that adobe bricks are waterproof – but the fact is they’re not.
However, adobe bricks can be easily finished and made nearly water-resistant with the following methods:
- Firing adobe bricks in a homemade kiln
- Sealing the adobe wall with paint or epoxy
- Covering walls with 2-3 coats of portland cement or mud
- Covering the bricks with two coats of concrete or stucco spray
Once you’ve taken these steps, your adobe wall will be nearly waterproof and strong enough to last a long time.
However, I recommend leaving at least one wall of your adobe home unfinished to give the house a unique and rustic look while keeping your home cool in the summer and warm in the winter.
The bottom line
Adobe homes are a great way to save money, but only if they’re properly sealed and made nearly waterproof.
No matter how you choose to paint, finish or make your adobe bricks waterproof, it’s important to remember that adobe is not an indestructible material.
To get the best results, it is important to take the time to properly repair and seal your adobe walls before painting them.
With the right preparation, materials, and techniques, you can ensure that your adobe walls will be able to withstand the test of time.
Jack Luis is a semi-retired painter who loved painting his clients’ ideas on their walls.
He had worked as a painter for over a decade serving customers in areas such as Charleston, Mount Pleasant, Beaufort, and Georgetown, SC (South Carolina). Today in his free time, he likes to read and write about the newer techniques implemented in his profession. You may read more about him here or get in touch with him here.