Kilz Paint vs. Mold

Does Kilz paint kill mold or mildew?
The common belief that Kilz paint kills mold or mildew requires us to elaborate on this question and give a clear detailed answer.

Kilz is a brand well-known for its line of primer and paint products designed to cover and seal surfaces before painting. It is a type of primer that is specifically formulated to address issues such as staining, odors, and previous paint colors. Its main purpose is to provide a clean slate for the application of new paint, ensuring a uniform appearance and better adhesion. 

Kilz primers come in oil-based, water-based, and latex formulas, catering to different types of surfaces and project needs. Beyond primers, Kilz also offers specialized paints that can tackle tough stains and imperfections in various building materials. Their products are synonymous with quality in the painting industry and are often recommended by professionals for renovation and refurbishment projects.

Will Kilz Cover Mold?

In your fight against mold, you might think of using Kilz primer as a solution. Kilz can indeed cover mold spots on various surfaces, providing a seemingly clean and renewed appearance. This capability is due to the excellent adhesion and sealing properties that the Kilz primers are formulated to offer. 

When applied correctly, Kilz can act as a barrier, covering unsightly mold and preventing any existing stains from bleeding through the newly painted surface. 

However, while Kilz may conceal the mold, it’s critical to understand that covering mold is not the same as addressing the underlying issue. Mold spores can remain active even beneath the layer of primer.

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Will Kilz Kill Mildew?

Kilz may cover up the unsightly appearance of mildew on surfaces, creating a fresh facade, but it’s not a mildew killer. While it’s true that Kilz primers possess exceptional sealing capabilities, it’s essential to note that they were not designed to eradicate mildew or mold. These primers act more like a mask, hiding the visual evidence of mildew but not dealing with the root problem. For health and structural concerns, it’s vital to treat the affected areas with a product that’s specifically formulated to kill mildew spores. Only after fully addressing the mildew issue should Kilz be used as a primer before painting, to hinder any remaining stains from showing through. It’s a covering mechanism, not a cure.

Why Kilz Doesn’t Work for Mold

Kilz, while lauded for its sealing prowess, falls short when confronted with the critical task of eradicating mold. The crux of the issue lies in the biology of mold spores themselves, which are robust and determined survivors. Undeterred by the mere application of a sealant, mold requires treatments that are unforgiving to its survival. Kilz primers can encapsulate existing surface mold and may help prevent future mold growth, but the foundational issue persists beneath the surface. To fully tackle mold, you’ll need to reach for antimicrobial and antifungal solutions that attack mold at its core. 

These products are specifically engineered to not only obliterate the visible sign but also neutralize the spores, decisively ending its potential for regrowth and ensuring a healthier living environment. Only when mold is effectively killed and removed can Kilz be utilized as a dependable primer for repainting.

What is Kilz Paint Used For?

Kilz paint, primarily recognized as a high-quality primer, is used for covering and blocking out difficult stains on surfaces before painting. Its application serves as a preparatory stage for the final paint job to achieve a uniform and smooth finish. Especially effective on surfaces affected by water damage, smoke, or grease, Kilz ensures that any discoloration or previous layer of paint doesn’t bleed through the new coat. It is also employed to seal porous surfaces like new drywall or wood, enabling the topcoat of paint to adhere better and last longer. More than just a stain-blocker, Kilz is a trusted ally in achieving a pristine, professional-looking paint job that effectively covers the old, unwanted marks and prepares the wall for a fresh new hue.

Best Alternatives

When dealing with mold or mildew, the primary concern should always be its complete removal for health and safety reasons. Painting over these issues can temporarily mask them, but ultimately, it doesn’t kill mold or mildew. Hence looking at alternatives is crucial. One of the best methods to tackle mold is to use a mold-killing primer. These primers contain antimicrobial properties that actually kill the mold spores, rather than just covering them up. After eliminating the mold, the area needs to be thoroughly cleaned and dried before any painting begins. In addition, you can turn to natural alternatives such as vinegar, which is a mild acid, capable of killing most species of mold. Professional mold remediation is also a safe bet, ensuring the problem is addressed at its source by those with expertise in mold elimination.

Final Thoughts

In conclusion, Kilz paint alone is not a one-stop solution for mold and mildew problems. It may be an excellent product for priming and preparing surfaces before painting, but the underlying issue of mold or mildew must be tackled head-on with appropriate cleaning and mold-killing treatments. While Kilz can offer a temporary cover-up, it’s important to address the root cause to ensure a healthy and safe environment. Ventilation, moisture control, and proper remediation are the real keys to removing these harmful fungi from your home. Always consult with professionals if the situation seems beyond your expertise, and remember, a clean, mold-free surface is crucial for the longevity and effectiveness of any paint job you undertake.


I enjoy acquiring knowledge and sharing it. I am a long-time health advisor and blogger for over 12 years. Understanding the dangers of black mold to people, I felt it necessary to share with readers the basics of fighting and preventing black mold in homes and other living spaces.

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