The following are some questions that can come up during discussions on the unique needs of adobe in Tucson or other areas where adobe bricks are found:
Q: Does my adobe and rammed earth home need to be sealed?
A: This depends on several factors, but generally speaking, yes: adobe and rammed earth homes need to be treated with a quality water repellent formulated specifically for adobe, like the Silox Adobe Water Repellent. Click here for the Silox information and ordering page. For information on protecting and preserving your rammed earth home, wall or building, click here
The video below will help to explain this:
In helping to answer this question, the first and most important consideration is the style of adobe home you have.
Basically, there are two style of adobe homes: Santa Fe and Ranch. A Santa Fe style is what one typically envisions when they think of an adobe home: high sculpted walls with rounded corners and tops (parapets) with a flat roof. No overhangs except for a front and back porch. Most of these walls are not protected. The photo directly above is an example of the Sante Fe style home. This particular one was designed by the famous Josias Joesler in Tucson, AZ (click on photo to enlarge).
The photo above shows another burnt adobe home constructed in the Santa Fe style. Typically these adobe homes are stuccoed. But here in Tucson, Santa Fe style adobe homes are not usually stuccoed and the adobe is left “out in the open,” so to speak. The adobe that these homes are constructed of are known as “burnt adobe,” or adobes that are made in Mexico and fired in brick kilns, usually being orange or reddish orange in color. These homes usually must be sealed to maintain their longevity.
The Ranch style homes pictured above are more or less a long rectangular shape with a pitched roof. This often has overhangs of between 1′ to 4′ surrounding most of the house. In essence, most of the adobes on this style of home are protected by the generous overhangs (except for the gabled ends where there is little overhang), particularly is the overhangs are 4′ in width.
Like the Santa Fe style homes here in Tucson, these are not stuccoed and are also made from “burnt adobe.” Most of the time these homes, being protected by the generous overhangs (of at least 4′), do not typically need to be sealed…the generous overhangs and wide porches provide the best possible protection for the adobes.
There are always exceptions, of course. For example, if you have a ranch style home with generous porches and overhangs but have flowers and other water hungry plants that require constant watering and are planted next to the walls of your adobe home, your generous overhangs probably are not going to help you.
Adobes are like sponges; they absorb and retain moisture. One of the poorest design and landscaping choices an adobe homeowner can make is to plant water hungry plants of any kind next to your adobe walls. The water from your hose or drip irrigation system will be absorbed by the adobes, and depending on which side of the house receives the greatest amount of watering, this can be disastrous for your adobes.
Houses facing north receive the least amount of sunshine and stay damp longer than the south or west side of a home. Rose bushes planted on both the north and west side of your home right against or close to your house walls (always a bad design choice for adobe home owners) and receiving the same amount of water will be absorbed at different rates by the adobes, particularly during the summer months.
The adobes on the west side of your home, receiving the same amount of water as the north side, will dry out much quicker, while the adobes on the north side will retain the moisture much longer and thus are more prone to being damaged by the excessive moisture being absorbed into them.
Q: I recently purchased an adobe home but am not sure whether or not it was sealed. I want to make sure my new investment is protected. Is there a way to tell whether or not the previous homeowner had it sealed?
A: Yes. Here is a quick and simple test to determine whether or not your adobe walls have been sealed: take a small pan of water or a big cup, fill it with tap water, and toss that water against all four sides of the home. If the water beads up and bounces away (like water on a duck’s back; see picture below), or if the water runs off without immediately absorbing and turning the adobes a darker color because of the water being immediately absorbed, they are protected.
If the water immediately absorbs and you can see an obvious darkening of the adobes compared to the other adobes that did not receive water, you are overdue for an application of a quality water repellent. The picture of the mud adobe wall above perfectly shows this.
If your home was previously treated, it’s possible that the north side—the shaded side—may still show signs of being previously sealed while the sun facing sides, particularly the south and west sides, may not. The hot, intense desert sun degrades paint, water repellents, and stains at a much quicker rate on the sun facing sides of homes than the protected north sides. This is why you should perform this water test on all sides of the house. If all four sides of your house immediately absorb the water and darken the adobes, the home has probably never been treated.
Q: If I have plants around my house as you described above, will sealing those adobes prevent the water from damaging them?
A: Unfortunately, no. All “sealers,” and I prefer to use the more accurate phrase “water repellents,” (I go into some length on this in one of the chapters of my book) are intended for occasional, irregular water issues, like the occasional rains we receive in the desert regions.
But no “sealer” or water repellent is made to prevent moisture from entering into a surface that is receiving continual, regular moisture, like what you have when you have plants that you water as described in your question.
Even if you treat those adobes with a quality water repellent like the Silox Adobe Water Repellent, this will not stop the water from leaching into these adobes. A thorough application of a quality water repellent will certainly help, but it will not offer you the kind of protection you are looking for.
Q: What kind of sealer or water repellent do you recommend for treating my adobe?
Made especially for adobe. Excellent product. Click the bolded words above to be taken to the page for ordering information.
Q: Where can I purchase the Silox?
A: It is available for pick-up in Tucson. We also have a retail outlet in Phoenix, AZ and Sedona, AZ who now carries the Silox: Spectrum Paint Company, located at 23043 N. 15th Lane (Phoenix) and 65 Brewer Rd (Sedona). Call Gary at (623) 606-7493 for store information in Phoenix and Sedona.
If you are outside of Tucson, give me a call or text (520) 331-4004 or send me an email at email@example.com for ordering information. Click here for more information.
Q: I have been reading that any type of water-repellent that is applied to my adobe must be able to “breathe.” Does the Silox allow the adobe brick to “breathe”?
A: Yes. The Silox was formulated specifically for adobe and it does allow the adobe to breathe.
Q: I think my home might be built out of adobe, but I’m not sure.
A: If you have a smart phone, simply take a picture of it and text it to me at (520) 331-4004. Or, take a picture of it and email it to me at “firstname.lastname@example.org”.
Q: I don’t live in Tucson and my adobe house has some real problems. Do you do consulting?
A: Yes. Click here for information.
Q: You have written that having water-hungry plants—like rose bushes—around the perimeter of my adobe walls, is a potential disaster. Please explain.
A: This is true.
One of the worst things an adobe homeowner can do is to plant these water-hungry flowers or plants in a planter box constructed out of adobe where the wall of your home is incorporated into the planter box itself.
If you have spent any amount of time reading this website, you will learn that adobes are like sponges…they absorb an incredible amount of water. And water and adobe don’t mix; water intrusion into adobe is the #1 cause of their deterioration.
Adobes need to “breathe” to stay healthy. Inevitably they will get wet, and this moisture needs to dry out. If not, the adobes risk being weakened and damaged; the longer they remain wet, the greater risk they have of suffering damage and deterioration.
Adobes are a building material primarily intended for a dry, low humidity environment, exactly what you find in a desert area like Phoenix or Tucson. They are not meant for an area that receives a lot of rain, like in Hawaii, the northern United States, or places back East.
Since water is the number one enemy of adobe, places that receive a significant amount of yearly rainfall are not ideal for adobe construction. When you water flowers that need regular and consistent watering, especially thirsty ones like roses, even if you live in Tucson or Phoenix that don’t receive a high annual amount of rain, you are defeating the purpose of building adobe in the first place.
I see this problem frequently: damaged adobes caused by over watering of plants and flowers located mere inches from the walls of adobe homes. And like I mentioned above, planter boxes made from adobe where the back of the planter box is the wall of an adobe house is disastrous.
Inevitably, watering plants in any type of planter box where the back wall of the planter box is your adobe home is an almost guarantee that the adobes, particularly the ones that make up the back wall, will suffer an incredible amount of deterioration.
I always recommend my customers remove all water-hungry plants from the immediate area of their adobe walls; every wall, even the adobe walls surrounding your pool or which encloses your backyard. If you need to water these plants every day or three or four times a week, you will ruin these adobes.
When I write “remove all water-hungry plants from the immediate area” of your adobe walls, what exactly do I mean? This means a distance of, at the very least, two feet from your walls; a minimum distance of three feet is preferable.
I understand, though, that many homeowners enjoy their flowers and other decorative plants. No one wants to live in a house devoid of color and beauty on the outside of their home. My suggestions for those adobe homeowners who currently have water-hungry plants and flowers in these adobe planter boxes is to remove them and replace them with decorative cactus or other low water use plants.
The alternative, of course, if you simply must have these water-hungry plants in the immediate vicinity of your adobe walls is to plan on regularly spending money to fix the adobes that will inevitably become damaged. You can also insure that the slope of the soil causes the water to run away from the walls instead of toward them.
But again, it must be stressed that adobe and water don’t mix. If you want to preserve your adobe home from costly repairs and potential catastrophic damage, don’t plant water-hungry plants and flowers within three feet of your exterior house walls.
Q: My house is built out of rammed earth? Can I use the Silox Adobe Water Repellent to protect my walls?
The Silox is an excellent product for protecting rammed earth walls. One of the issues with rammed earth (and I don’t wish to suggest rammed earth is a poor building choice for homeowners; rammed earth is my favorite building material) is that it “sheds” small particles onto the ground.
This is not much of an issue if these small particles fall onto the dirt, but if you have expensive flooring on the inside of your home, like wood flooring, these particles can certainly damage the flooring if ground under one’s feet as they walk through the home.
The Silox solves up to 98% of this problem by “locking” in or “stabilizing” the dirt particles, preventing them from falling to the ground, saving your expensive flooring from potential damage.
Q: I have cracks in my adobe walls. Is this something you can repair?
A: Yes. Unfortunately, cracks are the only repair items not guaranteed by Adobe Masters. The reason is because we cannot stop the ground from settling or shifting underneath your home, nor can we control tremors in the earth or even earthquakes…all scenarios that contribute—or can contribute—to cracks in your adobe walls.
Repaired cracks are notorious for re-opening, sometimes within days of having them repaired. This is why I recommend that adobe homeowners with cracks in their walls not be overly concerned with repairing them. Unless the cracks are so large that insects and bugs are coming through to the inside of your home, allowing water to seep through, need to be done to insure the integrity and safety of the walls, or if you have an excess of money that you don’t mind throwing it away on a repair that you will probably have to have redone in a couple of years or less, wait until you get ready to sell your home.
Nobody wants to see cracks in a home they are interested in purchasing. Before you put the house on the market, have a professional like Adobe Masters perform needed crack repairs to make the home look in top shape. As long as you ethically disclose to the buyer that you had the cracks repaired, waiting until you sell your home to make this improvement makes the most sense.
Q. My outdoor patio floor and walkway is made from adobe pavers. Many of these are deteriorating. Two questions: can the damaged pavers be repaired and will the Silox Adobe Water Repellent protect them from further damage?
A. Though adobe pavers in an exterior application can be repaired, my over 30 years of experience in dealing with adobe counsels against undertaking such repairs.
Why I say this is because adobe is made out of dirt and the number one enemy of adobe is water. When water and dirt meet, the integrity and strength of the paver is compromised. Patios and walkways, especially in installations around pools, waterfalls, plant beds, ponds, sprinkler systems, etc. are particularly vulnerable to deterioration from water infiltration.
Adobe pavers should rarely—if ever—be used in exterior installations. The only possible situation might be underneath a spacious porch where the pavers are completely protected by the porch and no water is allowed to come in contact with the pavers.
Early in my restoration career and before I gained the needed knowledge and experience to properly understand the unique needs and limitations of adobe, I would attempt to repair deteriorated adobe pavers, including severely deteriorated ones that were wholly exposed to the elements. I learned that repairing these were usually a mistake because, again, adobe protects used in exterior flooring settings are not a wise choice, especially in areas where water is a regular occurance.
Repairs in these areas don’t normally last long and will soon fall apart. Another option is to remove the damaged paver and replace it with a new one, but there is potential problems with this choice as well. Few homeowners have left over pavers stored around their property from the original installation and the new paver may be little in comparison to the original in color, exact dimensions, texture, or composition.
If by chance the homeowner does have some original strays hidden away somewhere, these will probably not match the others: years will have passed since the original flooring was laid down, and the subsequent years and decades will have altered the color and weathering patterns seen on the originals.
There is always the potential of damaging the surrounding undamaged pavers in the attempt to remove the deteriorated one(s) for replacement, setting up a potential chain reaction of needing to replace a series of pavers when only several needed attention.
Will the Silox Adobe Water Repellent protect adobe pavers from deterioration? Yes, but not adequately. Adobe pavers, like most adobes, act like sponges when they come in contact with moisture, absorbing vast amounts of water. A speciality adobe water repellent like the Silox—for the most part—protects the surface of the block primarily from one side: the side it was treated; in most instances, this side is the only side able to absorb the water repellent due to the fact that most adobes are in house walls where only the exterior face can be treated.
This one side of the home’s exterior walls are the ones that need the protection because they are in contact with the elements on one side and are protected from the elements on all other sides—generally speaking. But adobe pavers, installed on the ground, are in contact with the earth, absorbing moisture from rain, run off from roofs, splashing from pools and fountains, sprinkler systems, etc.
If adobe pavers are treated with a water repellent after installation, only one side of the paver—facing the sky—is the only portion of the paver protected by a quality water repellent. But a tremendous amount of water and moisture may also be absorbed from the unprotected bottom of the paver in contact with the ground, allowing the adobe pavers to be weakened and suffer deterioration even though the sky portion is protected.
Further, water repellents are not capable of protecting adobe from the continual presence of water, i.e., standing or pooling water; they are formulated to protect the occasional presence of rainfall against vertical surfaces, not from puddling on horizontal ones.
Adobe is primarily a product of hot, dry geographical areas typical of the desert found in the southwest regions of the United States with relatively little annual rainfall. Adobe can withstand periods of intense rainfall if it is allowed to throughly and quickly dry out, situations that typify desert environments which makes building homes out of adobe an ideal choice if certain practices are followed.
Adobe is not meant for exterior applications where the material is in contact with the ground. One reason is because they are unable to easily and quickly dry out after a dumping summer monsoon. Laying on the ground, they remain wet far longer than what walls constructed out of earth normally fare. Since water is the number one enemy of adobe, the longer adobe is in constant contact with moisture, the more prone they are to deterioration and ruin.
A specialized adobe/rammed earth water repellent like the Silox is formulated to protect earthen surfaces from the occasional—even heavy—summer downpours; the Silox is not formulated to protect adobe and rammed earth from continual, long-term contact with water. This is done on purpose, because as I have written elsewhere, there is a necessary and critical difference between a “water repellent” that is safe for protecting adobe and a true “sealer” that will, long term, harm the adobe. In general, sealers can trap moisture in; water repellents allow moisture out. Breathability is key to the success of any product primarily intended to protect earthen surfaces.
After almost 40 years in preserving and protecting adobe homes, my response to a customer who calls me and asks, “What should I do to repair my backyard adobe walkway that surrounds my pool and barbecue? It is looking terrible!”
My response is, “Do nothing. Save your money. Enjoy it while it lasts, and when you can no longer stand looking at it or if it becomes a trip hazard, tear it completely out and redo it with concrete pavers.”
Q. But what about stabilized adobe pavers, made with certain cements and/or other additives that the manufacturers claim will make them suitable for exterior applications, even in high moisture areas like around pools?
A. Such products are, of course, more weather resistant than unstabilized products, but I have never seen a stabilized adobe paver—or any stabilized adobe—that is suitable for longterm use in exterior applications exposed to the elements.
Certainly there are boastful claims made by manufacturers of such products, but let’s see how they perform long term in typical wet/damp areas and then make our decisions based on unbiased and factual science. Until that day comes, I will advise all of my readers, clients and customers to stay away from all such earthen floor products.
Q. I have what looks like black mold on parts of my adobe walls and I’m planning on sealing all the adobe soon. Is this black stuff a problem? Can I seal over it or should it be cleaned off first?
A. It sounds like you correctly identified the issue: black mold, which is common on burnt adobe homes. Green mold and/or moss is also common on burnt adobe walls.
Mold, whether it is black, green or other colors, is caused by excessive moisture that does not have sufficient time to dry out in the heat or sun. If you are experiencing this issue, you will probably find that these areas are typically found on the north and east sides of your home in the most shaded areas where the sun is shaded, filtered, or not often hitting that particular area.
These areas are typically found underneath rain scuppers and downspouts or directly underneath potted plants sitting on top of your adobe walls. Moss and mold need regular sources of moisture, and these mentioned areas are main sources. Since most mold and moss grow on the north and east sides of the home in shaded areas, a combination of excessive water and no to low sun exposure is the cause of this problem.
Black mold—and especially green moss—should be removed, especially if you are planning on sealing the adobe. Depending on how thick the mold or moss is, it can inhibit the necessary penetration of a water repellent like the Silox from penetrating into the adobes. Also, if you apply a water repellent over the mold or moss, you are “locking in” that mold or moss into the adobes, making it more difficult to remove at a later date.
Mold or moss is usually easy to remove. Some contractors tell customers they will use their pressure washers to remove it, but I’m hesitant concerning this method because adobe is soft enough that it can sustain damage by the use of a pressurized water blast applied with the necessary, sufficient force needed to remove the mold or moss.
A better and safer method, though more laborious and time consuming, is to take a solution of 1 part bleach to four parts water (or adjusted up or down depending on the stubbornness of the mold or moss) in a bucket of water and, using various styles of nylon type cleaning brushes commonly used to clean kitchens or bathrooms, attack these areas with some elbow grease. Experiment with different kinds and brands of nylon brushes with various types of stiffness in the bristles along with differing handle styles and widths; some work better than others.
You probably won’t be able to remove 100% of the problem because the mold or moss will penetrate into the little holes, voids, and cracks in both the adobe itself and the surrounding mortar joints, but you should be able to remove the majority of it. Insure you thoroughly rinse the area after using the bleach/water solution so that no bleach residue is left on the adobe to possibly interfere with the effectiveness of the water repellent.
The picture above shows a typical situation where black mold is growing directly underneath a rain scupper on a Joesler designed adobe home in Tucson. Interestingly, this faces west where the intense sun is the greatest. There is shade in this area, but the presence of black mold on the west side of a home in Tucson is slightly unusual; you commonly only find these areas on north facing walls in continually shaded areas.
I suspected a leak in this area. If you look closely at this picture (click on it then blow it up), you will see a galvanized water line at the bottom of the wall, half-buried in the dirt. This line connects to a PVC water line that extends around part of the backyard wall you can barely distinguish to the right of the house wall.
Where the galvanized line connects to the PVC, the realtor who called me out to look at this house informed me that it was leaking. But that leak was “downhill” from the mold spot and I suspect that the buried galvanized pipe, probably over 50 years old, was leaking and keeping this area under the scupper continually wet. With the rains, this area rarely, if ever, had a chance to thoroughly dry out, even facing the western sun.
In a situation like this one, be on the alert for leaking water lines or a natural “bowl” directly underneath a scupper which holds rainwater. Rain cascading down to the ground from this height from this style of scupper will inevitably form a depression in the ground underneath, holding the rainwater.
This can be solved through several changes. You can replace the dirt with rocks so that the rainwater no longer can carve out a hole, or you can dig the area out and contour the ground so that the water gushing down will lead away from the house…never toward the house or settling in a depression at the base.
I’ve seen homeowners lean a generous sized slab of flagstone against the wall where the black mold is seen, preventing the splash back of the rainwater from hitting the adobe wall. This helps. Remember: mold, whether black or green, only occurs with excessive moisture that does not have a chance to thoroughly dry out. Look for leaking water lines or any other issues that contribute to that exact area remaining moist for too long. Solving this issue will usually solve your mold problem.
It is important to allow any scrubbed areas to thoroughly dry before applying the Silox; remember, these affected areas are usually in shaded spots, and it will take longer for these cleaned areas to dry out than areas on the south or west sides of your home.
To lessen the chance of the mold/moss returning after cleaning, remove and stop watering your potted plants on top of your adobe walls. For areas under scupper/downspouts, place rocks or large pieces of decorative flagstone or something similar against the bottom of the walls where the water splashes to avoid the splash back of the falling water from hitting the walls, if possible.
Thin out heavy plant growth that may be preventing walls from more effectively drying out. It is never a good idea to have vines or plants growing on, over or around adobe walls; this shades the adobe and prevents air from circulating and drying out the walls, contributing to both mold and moisture penetration which causes damage.
Q. My house is built from slump block…does that need to be sealed? If so, would the “Silox Adobe and Rammed Earth Water Repellent” help to keep it dry when it rains?
A. Slump block and concrete block homes or walls can benefit from being treated with the Silox; though I have sprayed less than a handful of slump block homes in my long career, slump block and concrete block, like adobe, are sponges and soak up an incredible amount of water.
I’m writing this on Monday, July 26, 2021. Tucson, in the past week, has experienced an incredible amount of rain; almost every day for the past four or five days, it has rained. On Saturday and Sunday, it seemed to rain all day on both days. The Rillito Wash, normally bone dry, was raging; in some places, bank to bank. It was incredible how much rain we had.
I have a concrete block wall that surrounds three sides of my property and it was soaked with all the rain it received. I have never treated it with the Silox or any other brand of water repellent. It is untreated. Here is a picture of what it looks like today, in the early evening:
This section of the wall is facing north. Today, it was sunny and hot all day, with temps in the 90’s. Humid and muggy. But notice how wet this wall remains. If someone’s house was built out of this kind of block, or with slump block, I can only imagine the potential for mold and other water damage that might occur inside the home after being subjected to so much rain.
If this wall was treated with the Silox, it would not look this way…it would be dry. I know this because here is a picture of a burnt adobe “test” block that I treated with the Silox Original years ago that is sitting, right now, near this same wall. I took this photo right after I snapped the picture of the wall:
The left side was treated with the right side untreated. This block sits outside, with no covering over it except for the branches of a mesquite tree. I think this picture speaks for itself. All this to say, treating your slump block or concrete block home with the Silox can certainly help to protect it.
Q. Some of my interior walls in my adobe house are painted and I want to remove it. Is this possible? How do I go about removing the paint?
A. Yes, but it is time consuming and costly; you may not end up with the look you are hoping to achieve.
Years ago, a customer called me who wanted me to remove the paint from two interior walls. I had never done this before but foolishly thought, “It can’t be that hard,” and accepted the job. I used a chemical stripper called “Peel Away” that came in gallon containers and used this. It was one of the hardest and most frustrating jobs I’ve ever done.
The chemical worked good to remove the several layers of thick paint that had been put on these burnt adobe walls, but it took multiple and laborious passes of the stripper. Even when I had removed all the paint from the adobe that I possibly could, the paint was still locked within the various pits and crevasses of the adobe and mortar joints that I was never able to get out.
I could not remove all the paint from the adobes and return the wall to its unpainted condition. The best I was able to achieve was a whitewashed look that, to me, was quite pleasing. My customer was satisfied and that was all that counted, but it took me so long to do that I believe I basically worked for minimum wage on that job (when minimum wage was about $6.00 or $7.00 per hour).
The mess was extensive, with the multiple layers of paint all over the drop cloths and masking I laid down on the floors to protect it from damage from the stripped paint. It was such a tedious and labor intensive job I have never done another one and have no desire to repeat that experience.
Some people have tried sandblasting the adobe. Because there is different kinds of adobe, some much softer than others, I imagine you would get mixed results. The one job I remember that was sandblasted was horrible: it pitted the faces of the adobes so much that it was better left, in my opinion, the way it was.
My opinion on sandblasting is that it is not good and results in too much damage to the relative fragile adobes. But there is one method I learned about years ago, soda blasting, that might have promise. You use a special blasting machine that uses baking soda instead of sand and, supposedly, this does not damage the adobe faces too much. I’ve never tried it or seen it done, but it sounds promising.
Recently (March of 2022), a customer called me because her and her husband want to purchase a burnt adobe home and some of the interior walls are painted (very common). She was thinking of taking a hammer and chisel to these walls and trying to remove the paint this way.
I reminded her that “there is always more than one way to skin a cat” and that, though this method could work, I would not recommend it because of the damage it would certainly do to the adobes. Plus, the amount of work and time that would take to do even a small area would be unimaginable to me.
If you have artistic skill, re-painting the walls to mimic the original look of the adobes and mortar joints might be possible. Skilled artists can do amazing things with color, and though I don’t have the degree of skill and talent to achieve this kind of results, I’m certain it can be done.