
Waterproofing your basement will save you from a future filled with repair bills, health issues, and—of course—loss of property.
So, how do you protect it from water leaks? For most professionals, the answer is Drylok or Kilz primers. Kilz is more affordable, but Drylok has robust waterproofing abilities. Both of these brands have top products in terms of quality, plugging leaks, and longevity.
But for new DIYers, it’s tough making a choice between these brands. To help you on this path, this article will compare the two primers in more detail. That way, you can make the best decision for your unique project.
Why Choose Between Drylok and Kilz Primers?
It’s pretty simple: No one wants a damp, mold-infested basement. These products provide a relatively low-cost solution to seal your basement’s foundation, walls, and floor.
Unlike regular paints that only bond to the surface, Drylok and Kilz primers bind to porous materials like walls to form a solid seal, preventing water infiltration and eventual mold.
Depending on the underlying coat on the surface, you may select a latex or oil-based primer. For example, the Drylok Extreme Masonry Waterproofer is an oil-based paint guaranteed to last for 15 years.
In addition to its longevity, it has a water resistance of 15 PSI. Its smooth texture is also a prized feature since it increases the walls’ aesthetics. At the same time, it contains a biocide to kill all mold and mildew growth.
In comparison, the Kilz 3 Premium primer is a low odor, fast-drying, water-based primer. It’s a top choice for professionals who want to block out heavy water stains and seal moisture within the surface.
The Kilz 3’s most exciting feature is its compatibility with most surfaces, including glossy, smooth surfaces. It works with both oil and water-based paints.
Now that you know why these products are the best fit for basement surfaces, let’s delve into the main differences between and best times to use these primers.

Main Differences Between Drylok and Kilz Primers
Drylok and Kilz Primers are better suited to solving slightly different problems. In this section, we’ll compare these products based on the following metrics: cost, quality, performance, and lifespan.
Kilz or Drylok: Which is More Affordable?
The cost of a primer matters in any buying decision. In most cases, you want the most affordable option without skimping on quality.
For this review, we’ll compare the prices of these primers on popular eCommerce stores. These prices may differ from your local hardware store.
On the Home Depot website, a gallon of Drylok Original Clear Waterproof primer costs $42, while it costs $35.98 for a gallon of Drylok Extreme primer. Kilz 3 Premium primer is considerably cheaper at $26.97 per gallon. You can also get a quart of the primer at $13.52.
Verdict: Kilz 3 Premium primer is a more affordable option.
Note: Drylok Extreme has a higher pressure rating than the Original version.
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Kilz vs Drylok: Which Performs Better?

Regardless of the cost, you want a good return on your investment. To compare the quality, we’ll consider longevity, capabilities, and versatility.
Drylok Extreme generally performs better than the Kilz 3 primer because of its superior water pressure rating. Drylok Extreme can withstand up to 15 PSI of water pressure, while Kilz 3 has a lower 12 PSI rating.
Drylok Extreme performs better on bare concrete walls and floors as well. However, you can use Kilz Primers on any surface, including surfaces with an existing coat of paint.
In terms of finishes, Kilz primers leave a thicker coat and provide smoother finishes on any surface. The Drylok Extreme and Original primers seep into porous concrete surfaces and wood to create an impenetrable layer to stop water from seeping through.
Drylok Extreme has high tensile strength and can withstand water pressure up to 15 PSI. This prevents high-pressure water or moisture from leaking and staining the walls. It also comes with a 15-year warranty, making it perfect as a long-term solution.
Both the Drylok Extreme and Original are anti-mold primers containing biocides, chemicals that prevent mildew and molds from growing on wall surfaces. Besides protecting against mildew, these primers prevent salty powdery deposits on basement and masonry surfaces.
Kilz 3 Premium is the most potent waterproof primer in the Kilz product line. It is an upgrade from Kilz 2 and can withstand up to 12 PSI. Furthermore, it has a better sealing ability than the Kilz 2 primer. Only a coat or two is needed to hide stains from pet urine, cigarettes, and mold.
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Drylok vs Kilz: Which Has Better Coverage and Dry Time?

The rave is all about fast-drying primers. These primers save time by reducing the time between adding additional coats of primer.
Drylok Extreme primer will become dry to touch within 45 minutes and be ready for a recoat in two hours. According to the Kilz official website, the Kilz 3 Premium primer will dry within 30 minutes at ideal temperature and humidity levels (50% RH and 77°F or 25°C).
You may choose to recoat with another primer, oil, or latex-based paint. But a single coat of Kilz 3 Premium is often enough for most minor stains.
Note: Lower temperatures combined with high humidity will lengthen the dry time. Try to ventilate the room when working with waterproof primers.
Should I Use Kilz Before Drylok?
Yes, you can paint over Drylok primers with Kilz. Drylok allows latex paint to be applied to it. Wait for at least a day before painting over Drylok primer.
Conclusion
The Drylok Extreme seems like the better choice since it has a high resistance to water pressure. But ultimately, select the primer that best fits your preferences. Take advantage of this information and get the best primer for your DIY painting project, whether it be Kilz or Drylok.