As a homeowner, you may be surrounded by questions concerning stucco when considering how to protect and beautify your home. One such question is “Can I put new stucco over old stucco?” The short answer is yes—in some circumstances it’s possible to apply new stucco atop an existing layer.
This article will address the factors to consider before doing what’s known in the residential, commercial and industrial painting industry as a “scratch coat”, during which new stucco is applied on top of old. We’ll discuss what types of conditions make putting a new stucco layer suitable as well as the advantages and disadvantages to this approach.
What is Stucco?
Stucco is a composite material used for decoration and protection of interior and exterior walls. It’s usually made from sand and cement but can also include other materials like lime or acrylic polymer. Used extensively since ancient Roman times, stucco was a preferred building material due to its water resistance, fire resistance, and durability. It looks great too, with a wide range of textures, finishes and colors available that make customizing the look of any property remarkably easy.
Stucco is a durable material, but if you’re curious about exactly how long it can last, check out our article on the lifespan of stucco.
What Is The Most Important Factor To Consider When Deciding If I Can Put New Stucco Over Old?
Since compatibility of old and new stucco will not be an issue, the most important factors to consider are durability, color, texture and finish. Depending on the construction and substrate of the building, in some instances it may be acceptable to use a relatively strong cement-based stucco mortar.
How Do I Know If My Existing Stucco Is In A Condition That It Can Receive New Stucco?
You can do this by examining the surface of the stucco for cracks, chips, or other signs of damage. If the stucco is in good condition, a new coat can be applied over the old stucco. If the stucco is in poor condition, however, the old stucco will need to be removed before the new coat.
Are There Any Limitations With Putting New Stucco Over An Old One?
If the painted surface is in very good condition, you can apply stucco directly over it, as long as you use a bonder. When dealing with efflorescence (a white powder or film on the wall composed of salt crystals left behind when salt-laden water evaporates), spray on vinegar or another mild acid to neutralize it. Then flush the wall with water to bring the pH level down to an acceptable level.
When the old stucco is in poor condition, it might be more appropriate to consider repairing rather than covering it. Read more about how to repair old stucco here.
Is There Anything Specific I’ll Need To Take Into Account Before Applying The New Stucco Layer?
The new layer should be between 1/8 and 1/4 inch thick. Work from the bottom of the wall and pull the mud upward for the best results. Use trowels to tool the stucco into your desired texture and look.
When planning to apply a new stucco layer, it’s important to consider whether it’s better to repair or replace the existing stucco. Learn more about whether it’s better to repair or replace stucco in our dedicated article.
Can Simply Mixing Plaster and Water Fix Up My Existing Stucco Instead of Replacing The Existing Coating?
Though technically possible, this is not recommended because the bond strength of the plaster alone is not sufficient enough to support additional layers or finishes.
Are There Any Disadvantages With Using a New Stucco Layer on Top Of An Existing Stucco Compared To Removing The Existing Stucco and Starting With a Clean Slate?
Generally, it’s best to start with a clean slate, especially when dealing with damaged or deteriorated stucco walls and surfaces. When stucco has been damaged or deteriorated it becomes weakened and more prone to developing new cracks, chipping and crumbling–all detrimental to the stability of the stucco wall. But if the stucco is determined to be in good condition, applying a scratch coat may be a viable option.
Similar to drywall, there are considerations when deciding whether to add new stucco over old. For more insights into this type of decision, see our article on whether it’s better to patch or replace drywall.
Conclusion
When deciding whether a new stucco layer can be applied over an existing layer, it’s essential to take all of the necessary steps to ensure the longevity and durability of the stucco. You’ll need to check the underlying structure of the stucco, the condition of the stucco and the substrates. And remember, sometimes starting with a clean slate is the better approach.
FAQs
Q: How thick should the new stucco layer be?
A: The new stucco layer should be between 1/8 and 1/4 inch thick.
Q: How can I test the condition of my existing stucco?
A: You can test the condition of existing stucco by looking for cracks, chips, or other signs of damage.
Q: Can I paint over the new stucco layer?
A: Yes, you can paint over the new stucco layer once the it has cured and been sealed properly.
Q: Will using a new stucco layer last longer than removing the existing stucco and starting with a clean slate?
A: In most cases, starting with a clean slate will produce the longest lasting finished product.
Q: How can I remove efflorescence from the existing stucco?
A: Spraying vinegar or a mild acid solution on the stucco surface followed by a rinse with water will lower the pH level, neutralizing the efflorescence.
Q: Will using a new stucco layer last longer than removing the existing stucco and starting with a clean slate?
A: In most cases, starting with a clean slate will produce the longest lasting finished product. But lifespan isn’t only a concern for stucco; if you’re interested in how long other types of coatings last, read about how long epoxy coating lasts.
Applying new stucco over old can be a challenging task without the right experience and knowledge. If you need expert advice or professional help, we’ve got you covered! We have skilled and experienced painters across several cities. Whether you’re looking for Maple Ridge painters, Langley painters, Richmond painters, New Westminster painters, West Vancouver painters, North Vancouver painters, Port Coquitlam painters, Coquitlam painters, Port Moody painters, Surrey painters, Burnaby painters, or Vancouver painters, we are ready to deliver top-quality stucco and painting services right to your doorstep. Don’t hesitate to get in touch with us, and let’s make your home beautiful and durable together!