The internet—and YouTube in particular—is a treasure trove of advice on every imaginable topic. Some of it is helpful. But when it comes to adobe preservation and repair, there’s also a troubling amount of misinformation that, if followed, can do serious damage to your adobe home.

Here’s a perfect example. I recently came across a YouTube video showing a mud adobe home being covered with cement stucco. Before the stucco was applied, the installer fastened chicken wire over the adobe walls. On the surface, it may look like a standard approach—but there are at least two major problems here.

Problem #1: The Chicken Wire and Nails

First, the chicken wire itself. Is it galvanized? Are the nails galvanized as well? Even if the answer is “yes,” that doesn’t guarantee the galvanization will hold up over time in this application. I’ve seen similar jobs where the chicken wire rusted through, breaking apart in places. It’s also possible the wire used here wasn’t galvanized at all—I didn’t test it to confirm.

Then there’s the nail issue. Typically, nails of at least 3″ are used—4″ is even more common. Driving nails of that length into adobe, whether hard or soft, risks cracking or shattering the blocks. Once damaged, those adobe bricks lose structural integrity, which can compromise the wall over time.

Problem #2: The Cement Stucco

This is the bigger problem. Adobe walls must be able to “breathe” to stay healthy. When adobe absorbs moisture, that moisture needs to evaporate quickly and easily. If it can’t, the trapped water will eventually destroy the adobe—turning it back into mud.

And adobe, being made primarily of earth, is the most susceptible of all building materials to damage and eventual destruction due to water infiltration. What happens to adobe if it gets water logged? It turns to mud. This is why adobe must be allowed to dry out when it does get wet, but applying a cement based product over the surface of the adobe interferes with this natural drying out process due to the nature of the cement based stucco. And the thicker this cement coating is, the longer it will take the adobe underneath it to dry out. Troweling on such a cementitious coating over the adobes traps any moisture which will penetrate into the adobe and prevent that moisture from easily transpiring back out of the adobe when a rainstorm passes through the area and the sun comes back out to begin the drying process.

Cement stucco interferes with this natural drying process. The thicker the coating, the slower the drying. And when moisture penetrates the wall (which it will, through hairline cracks, gaps, or capillary action), cement stucco traps it inside, where it can’t escape easily.

The problem gets even worse after stucco is painted, as is standard on most homes. Paint forms yet another barrier, further restricting the wall’s ability to breathe.

The “Raised Foundation” Misconception

The video’s title claimed: “I don’t normally cement plaster adobe. But with a raised foundation. (sic) It’s safe to do so.” In reality, the foundation shown was only about six inches high—far below my recommended minimum of eight inches. In truth, I prefer at least twelve inches, and two feet or more is even better.

While a raised foundation does help protect adobe from ground moisture, it’s only part of the equation. To make cement stucco reasonably safe, the builder would also need:

Absolutely no irrigation near the foundation.

A gabled roof with generous overhangs (four feet or more).

A complete gutter system that directs all water away from the walls.

Positive site drainage so runoff flows away from the home—nor towards the home.

Only with all of these safeguards in place—and with a 100% guarantee that no water from any source will contact the adobe walls—would I reluctantly agree that cement stucco over adobe could be safe on a raised foundation.

The Bottom Line

If you value the longevity of your adobe home, avoid cement stucco unless you can absolutely eliminate any chance of moisture contact. Adobe’s beauty lies in its ability to breathe—and once you seal it up with cement, you’re putting the material on a slow path to failure.

Below, I’ve linked another video from the same creator that actually proves my point about why applying cement stucco to adobe is risky at best—and disastrous at worst.

In the video, he says: “We removed the cement plaster from this adobe wall because I had a lot of salt damage, and sure enough, the wall was wet…” Keep in mind—this was an interior wall. Imagine how much moisture must be present on the exterior side of that same wall. What’s puzzling is that he doesn’t seem to connect the dots between this project and his other video. If cement plaster trapped enough moisture inside to damage an interior wall, why would he make the same mistake by applying a similar cement coating to the exterior?

What are the correct solutions to these kind of adobe walls? Lime based (Natural Hydraulic Lime [NHL]) coatings.