If you’re looking for the best primer for water stains, you’ve come to the right place. Dealing with water stains can be a frustrating and challenging task, but with the right primer, you can effectively cover and block those unsightly marks on your walls or ceilings. It’s important to choose a primer that specifically addresses water stains to ensure optimal coverage and long-lasting results.
Before buying a primer for water stains, there are a few key factors to consider. First and foremost, you need to determine the type of surface you will be priming. Whether it’s a painted wall, drywall, or plaster, the primer you choose should be suitable for that specific surface. Additionally, it’s important to look for a primer with stain-blocking properties, as this will effectively cover and prevent the water stains from bleeding through the new paint.
When searching for the best primer for water stains, ask yourself these questions. Does the primer have good adhesion to the surface? Is it easy to apply and quick-drying? Does it provide full coverage and effectively block stains? Is it low odor and environmentally friendly? By considering these factors and asking the right questions, you’ll be able to find the perfect primer to tackle those stubborn water stains and achieve a flawless finish for your walls or ceilings.
In conclusion, finding the best primer for water stains is crucial in ensuring a flawless and long-lasting paint job. By considering factors such as surface compatibility, stain-blocking properties, and overall performance, you can confidently select a primer that will effectively cover those unsightly water stains and provide a smooth base for your paint. Say goodbye to water stains and hello to a beautifully refreshed space.
10 Best Primer For Water Stains
Ideal for interior and exterior surfaces, this water-based primer/sealer ensures a smooth finish and excellent adhesion.
It is an ideal primer/sealer for blocking stains and odors on interior surfaces.
This product is ideal for priming and sealing surfaces with persistent and chronic moisture issues.
This primer is ideal for preventing and covering stains, including water, smoke, nicotine, and tannin stains, on various surfaces.
It is an ideal product for priming and sealing surfaces before paint application.
The product is ideal for priming surfaces before applying acrylic or waterborne paints.
This product is ideal for blocking stains and sealing surfaces.
This product is ideal for priming various surfaces with an acrylic formula.
The product is ideal for priming surfaces both indoors and outdoors, providing a versatile solution for various projects.
Zinsser 2001-2PK Bulls Eye 1-2-3 Water-Base Primer, Gallon, White, 2 Pack is ideal for priming surfaces before painting.
1. Zinsser 1 Qt 249727 White, Smart Prime Water-Based Interior/exterior Primer/sealer
Looking for a high-performance primer that works on any project? Look no further than this advanced water-based formula, which delivers the oil-based performance you need without any of the drawbacks. With its unique formulation, this primer sticks to all surfaces, both inside and out, and is specially designed to block all types of stains, including water stains.
One of the key benefits of this primer is its low-VOC, low odor formula. This means you can use it in any space without worrying about harmful fumes or unpleasant smells. And because it's water-based, cleanup is quick and easy – simply wash your brushes and tools with soap and water.
Whether you're tackling a small DIY project or a large-scale renovation, this primer is the perfect choice. It's versatile enough to use on any surface, including wood, metal, plaster, and more. And with its superior stain-blocking abilities, you can be confident that your finished project will look flawless for years to come.
So why settle for a subpar primer when you can have the best? Try this advanced water-based formula today and see the difference for yourself!
2. Maximum Stain & Odor Blocker Primer
Introducing KILZ RESTORATION Primer – the ultimate solution for all your painting needs! This water-based primer, sealer, and stain blocker offers the same level of performance as traditional oil and shellac-based primers, but with the added benefits of easy clean-up, low odor, and low VOC.
The advanced formula of KILZ RESTORATION Primer features a modified acrylic epoxy formula that provides superior adhesion and blocks tough stains and odors. It is perfect for restoration and disaster recovery painting jobs where you need a reliable product that can handle any challenge.
This primer works on a variety of surfaces, including drywall, wood, plaster, masonry, brick, painted metal, ceramic tile, glass, and most other glossy surfaces. Prior to application, surfaces should be free of dust, grease, chalk, rust, and peeling paint. KILZ RESTORATION Primer can also be used as a subcoat for flooring and carpets to block pet odors.
This 1-gallon can of KILZ RESTORATION interior latex primer covers approximately 300-400 square feet per gallon, providing superior coverage for your painting projects. It dries to touch in just 30 minutes and can be recoated or topcoated after one hour.
KILZ is a trusted brand that has been providing high-quality primer products for nearly 50 years. Their products consistently rank as one of the most trustworthy brands in the architectural coatings market. KILZ RESTORATION Primer comes with a lifetime limited warranty (see label for details).
3. Zinsser 1 Qt 260925 White, Peel Stop Triple Thick Ponding Primer
This versatile coating is perfect for restoring peeling or worn surfaces both indoors and outdoors. The triple-thick formula penetrates deep into the surface, bonding with cracks and peeling edges to provide a solid foundation for a smooth finish. This product is suitable for use on a variety of surfaces, including wood, metal, concrete, and more.
Drying to the touch in just 30 minutes, this coating can be recoated in just 2 hours, making it an efficient option for any project. Depending on the porosity of the surface, one quart of this coating can cover anywhere from 12-50 square feet. The resulting finish is smooth, flexible, and sealed, providing a foundation for a topcoat of any alkyd or latex paint.
This water-based primer-sealer is ideal for sealing worn surfaces and providing an outstanding level of flexibility. Whether used indoors or out, this coating is designed to create a smooth, sealed finish that will last for years to come. Once applied, this coating can be topcoated with any latex or alkyd paint, providing a level of versatility that is unmatched in the industry.
4. Rust-Oleum 1 Gal Zinsser 270976 White Zinsser, B-I-N Advanced Synthetic Shellac Primer
Introducing the Rust-Oleum Corporation 270976 Advanced Synthetic Shellac Primer, a high-quality painting supply designed to enhance your painting experience. This product is proudly manufactured in the United States, ensuring superior craftsmanship and reliability.
With its superior odor sealing properties, this shellac primer effectively eliminates unpleasant odors, allowing you to paint with confidence and create a fresh, clean environment. Say goodbye to unwanted smells and hello to a beautifully painted space.
Not only does this primer excel in odor sealing, but it also offers ultimate stain blocking capabilities. Whether you're dealing with water stains, smoke damage, or other stubborn stains, this primer is designed to provide maximum coverage and effectively block out unsightly blemishes. Achieve a flawless finish that will impress even the most discerning eye.
The high hiding bright white formula of this primer ensures that your paint color will truly shine. Say goodbye to dull, lackluster finishes – this primer acts as a strong foundation, enhancing the vibrancy and richness of your chosen paint color. Transform your space into a stunning showcase of color with ease.
When it comes to adhesion, this primer excels. Its excellent adhesion properties ensure that your paint adheres well to surfaces, providing a long-lasting and durable finish. No more worrying about peeling or chipping paint – this primer creates a strong bond between the surface and your chosen paint, ensuring a professional-quality result that will stand the test of time.
In addition to its impressive performance, this shellac primer also seals knots, sap, and tannin, providing a smooth and even surface for painting. Take the guesswork out of preparing your surfaces – this primer effectively seals and prevents bleed-through, allowing you to achieve a flawless finish every time.
Choose the Rust-Oleum Corporation 270976 Advanced Synthetic Shellac Primer for all your painting needs. With its superior odor sealing, ultimate stain blocking, high hiding bright white formula, excellent adhesion, and ability to seal knots, sap, and tannin, this primer is a must-have for any painting project. Transform your space with confidence, knowing that you're using a reliable and high-quality product. Don't settle for anything less than the best – choose Rust-Oleum.
5. Zinsser 2244 Bulls Eye Wb Primer Sealer, 1 Quarts (Pack Of 1), White, 12 Fl Oz
This versatile product is perfect for priming a variety of interior surfaces. Whether you're painting walls, doors, trim, plaster, or concrete, this primer will help you achieve a smooth, professional finish.
The water-based, low-odor formula is not only easy to work with, but it also provides exceptional stain hiding, even on dark or porous surfaces. You can rest assured that your final paint job will look flawless and uniform.
One of the best things about this primer is how quickly it dries. In just 30 minutes, it's ready to be top-coated with your favorite paint. And with coverage of up to 100 sq. ft. per quart, you won't need to use as much product to get the job done.
Another great feature of this primer is its ability to adhere to slick surfaces without requiring deglossing or sanding. This saves you time and effort, making your painting project even easier.
6. Insl-X Sxa11009a-01 Stix Acrylic Waterborne Bonding Primer, 1 Gallon, White
Introducing the INSL-X STIX Premium Bonding Primer-Sealer, a top-tier acrylic-urethane product that boasts exceptional adhesion to even the most difficult surfaces. With its unparalleled bonding power, this primer-sealer is designed to adhere to glossy tile, PVC, vinyl, plastic, glass, glazed block, glossy paint, pre-coated siding, fiberglass, and galvanized metals. It is truly a versatile solution for a wide range of challenging surfaces.
This bonding primer is not limited to specific areas either. It can be effectively used on drywall, plaster, ceiling, acoustical tile, wood trim and doors, Formica, ceramic tiles, glossy surfaces, PVC plastic, masonry walls, wood, trim, shutters, masonry, stucco, concrete, cement block, galvanized metal, aluminum, and other similar surfaces. No matter what project you have in mind, this primer-sealer will bond seamlessly, making it an ideal choice for both professional painters and DIY enthusiasts.
One of the standout features of the INSL-X STIX Premium Bonding Primer-Sealer is its ability to bond to "hard-to-coat" surfaces. This means you can confidently apply this primer to surfaces that are traditionally challenging to paint, knowing that it will create a strong foundation for any topcoat. Whether you're planning to use latex, oil-based, or any other type of paint, this primer-sealer can handle it all.
Additionally, this product offers the convenience of a low curing temperature. In fact, it can fully cure in temperatures as low as 35 °F, allowing you to work in various weather conditions without compromising the final result. This is particularly useful if you live in an area with unpredictable climate patterns.
When it comes to coverage, the INSL-X STIX Premium Bonding Primer-Sealer offers impressive results. With a range of 300 to 400 square feet per gallon, you can cover a significant amount of surface area with each can. This makes it a cost-effective choice for large-scale projects or multiple smaller ones.
Moreover, this primer-sealer boasts a low VOC (volatile organic compounds) formula, ensuring a safer and healthier working environment. It also allows for easy cleanup with simple soap and water, saving you time and effort.
Finally, the INSL-X STIX Premium Bonding Primer-Sealer excels in enamel holdout, providing a smooth and even base for your topcoat finish. You can expect a flawless and professional-looking result every time.
Before you start your painting project, it's always wise to review the INSL-X STIX label for proper preparation and application tips. This will help you achieve the best possible outcome and ensure the longevity of your paint job.
7. Zinsser 1 Qt 02004 White, Bulls Eye 1-2-3 Water-Based Stain Blocking Primer/sealer
This versatile product is perfect for both interior and exterior use, making it a great choice for a variety of surfaces such as drywall, concrete, wood, masonry, metal, and even glossy or difficult surfaces. Its water-based formula ensures uniform sealing and adherence without the need for sanding, saving you valuable time and effort.
In just 35 minutes, this product dries to the touch and is ready for topcoating in only 1 hour. With coverage of up to 112 square feet per quart, you'll get excellent value for your money. Additionally, its stain-blocking resistance is second to none, making it a reliable choice for a variety of applications, and it can be used with any oil or latex topcoat.
This product's one-coat hide feature is an excellent time and money saver, improving hide and coverage of topcoats. You'll appreciate its ease of use and versatility, making it ideal for both professional and DIY projects. With its excellent coverage, quick drying time, and superior stain-blocking resistance, this product is a must-have for any home renovation or painting project.
8. Insl-X Ap100009a-04 Prime All Multi-Surface Acrylic Primer, White 32 Fl Oz (Pack Of 1)
Introducing the 100% Acrylic Primer, a reliable and high-quality solution for sealing both interior and exterior surfaces. This primer is designed to provide strong sealing properties that can withstand various conditions.
One of the best features of this primer is its ease of application. It can be applied effortlessly, making it an excellent choice for both novice and experienced users. The primer's powerful adhesion and stain blocking properties are also noteworthy, making it an ideal choice for surfaces that require superior protection.
The quick drying time of the 100% Acrylic Primer is another impressive factor. The primer dries quickly, allowing users to apply a topcoat in as little as one hour. Additionally, this primer provides a mildew-resistant coating, making it an excellent choice for areas with high humidity.
It is important to note that the 100% Acrylic Primer should be applied when the surface and ambient temperature is above 40 °F (4 °C) and below 90 °F (32 °C). This will ensure optimal results and performance.
With a coverage of 400 – 450 square feet per gallon, this primer is a cost-effective solution that provides excellent value for money. However, it is not recommended for use on floor surfaces.
9. Kilz 2 All-Purpose Primer, Interior/exterior, 1 Gallon
Introducing the KILZ 2 Latex Water-Based Primer, Sealer, and Stainblocker. This high-quality primer is every painter's secret weapon, delivering exceptional results for both interior and exterior surfaces. With its reliable performance and impressive features, it's no wonder that KILZ has been a trusted name in the industry for 40 years.
One of the key benefits of using a primer is that it enhances the adhesion of paint to surfaces, resulting in a longer-lasting and more durable finish. The KILZ 2 primer excels in this aspect, providing a strong bond between the paint and the surface. Whether you're working on brick, painted metal, glossy surfaces, drywall, paneling, stucco, masonry, plaster, or wood, this versatile primer is up to the task.
Not only does the KILZ 2 primer enhance paint adhesion, but it also blocks mild to medium stains effectively. Say goodbye to unsightly water, grease, ink, pencil, and felt marker stains with this powerful primer-sealer-stainblocker. It also does an excellent job of hiding previous colors, allowing you to achieve a fresh and new look for your walls or ceilings.
Application is a breeze with the KILZ 2 primer. Simply ensure that your surface is properly prepared, free of dust, grease, chalk, rust, and peeling paint. Give the can a good mix before using, and then you're ready to apply the primer using a brush, roller, or spray. The primer dries to the touch within 30 minutes, and you can recoat after just an hour, making your painting project more efficient and time-saving.
This 1-gallon can of KILZ 2 Latex Water-Based Primer, Sealer, and Stainblocker in white covers approximately 300-400 square feet per gallon, allowing you to cover a significant area with ease. With its excellent coverage and reliable performance, you can trust that this primer will deliver outstanding results every time.
Choose KILZ, the Paint Brand of the Year in 2015 according to the Harris Poll EquiTrend Rankings. With their dedication to producing premium primers and paints, you can be confident in the quality and performance of the KILZ 2 Latex Water-Based Primer, Sealer, and Stainblocker. Upgrade your painting projects with this exceptional primer and achieve professional results that will stand the test of time.
10. Zinsser 2001-2pk Bulls Eye 1-2-3 Water-Base Primer, Gallon, White, 2 Pack
The [Product Name] is a versatile primer sealer that can be used for both interior and exterior applications. Whether you are working on new or previously painted surfaces such as drywall, concrete, wood, masonry, metal, or even glossy and difficult surfaces, this product has got you covered.
One of the great features of the [Product Name] is its water-based formula. This means that you don't have to worry about using any harsh chemicals or solvents during the application process. The water-based formula also ensures that the primer sealer will adhere uniformly to the surface without the need for sanding.
When it comes to drying time, the [Product Name] is quite impressive. It dries to the touch in just 35 minutes, making your painting project more efficient. In addition, it is ready to be topcoated in as little as 1 hour, allowing you to finish your project in a timely manner. With a coverage of up to 400-450 square feet per gallon, you can be confident that a little goes a long way.
Stain-blocking is another important aspect of any primer sealer, and the [Product Name] excels in this area. It has excellent stain blocking resistance, ensuring that any stains or discolorations on the surface will be effectively covered. Whether you are planning to use an oil or latex topcoat, this primer sealer is compatible with both, giving you the flexibility to choose the type of topcoat that suits your needs.
Another advantage of the [Product Name] is its ability to be applied in colder temperatures. With a minimum application temperature of 35 degrees Fahrenheit, you can confidently use this primer sealer even in chilly conditions. This makes it a great choice for both indoor and outdoor projects, regardless of the weather.
Best Primer For Water Stains FAQs
Are there any primers that also have mold and mildew resistant properties, in addition to covering water stains?
Yes, there are primers available in the market that not only cover water stains but also have mold and mildew resistant properties. These primers are specifically formulated to provide a protective barrier against moisture and prevent the growth of mold and mildew. They contain special additives that inhibit the growth of mold and mildew, making them ideal for use in areas prone to high humidity or water exposure, such as bathrooms, kitchens, and basements.
When selecting a primer with mold and mildew resistant properties, it is important to look for products that are specifically labeled as such. These primers are often water-based and may contain ingredients like zinc oxide or biocides that help prevent the growth of mold and mildew.
Before applying the primer, it is crucial to clean and dry the surface thoroughly to ensure proper adhesion. Additionally, it is recommended to follow the manufacturer's instructions for application and safety precautions.
If you are unsure about which primer to choose, it is always beneficial to consult with a professional paint supplier or a knowledgeable contractor who can provide guidance based on your specific requirements and the condition of the surface in question.
Are there any primers that are specifically designed for covering water stains on exterior surfaces, such as siding or fences?
Yes, there are primers specifically designed for covering water stains on exterior surfaces such as siding or fences. One such primer is a stain-blocking primer. These primers are formulated to effectively seal water stains and prevent them from bleeding through the topcoat. Stain-blocking primers often contain ingredients like shellac or oil-based resins that create a barrier between the stain and the topcoat. They are designed to adhere well to a variety of surfaces, including wood, vinyl, metal, and concrete.
When choosing a primer for covering water stains on exterior surfaces, it is important to look for one that is specifically labeled as stain-blocking or water stain primer. These primers are formulated to provide maximum coverage and adhesion, ensuring that the water stains are effectively concealed.
It is also recommended to thoroughly clean and dry the surface before applying the primer, as any dirt or moisture can affect the primer's performance. Additionally, following the manufacturer's instructions regarding application and drying time is crucial to achieve the best results.
Are there any primers that claim to completely block water stains from bleeding through?
Yes, there are primers available in the market that claim to completely block water stains from bleeding through. These primers are specifically designed to prevent water stains from penetrating through the surface and causing discoloration or damage to the paint or finish.
One such popular primer is a stain-blocking primer that contains specific ingredients, such as shellac or oil-based formulas, which create a barrier against water stains. These primers work by sealing the porous surface and preventing the water stains from seeping through.
When choosing a primer for this purpose, it is essential to look for products that specifically mention their ability to block water stains. Reading product reviews and consulting with professionals at your local hardware store can help you find the most effective primer for your specific needs.
It is important to note that while these primers can significantly reduce the chances of water stains bleeding through, they may not provide a 100% guarantee in all situations. In some cases, multiple coats or additional measures may be necessary to completely block stubborn water stains.
Can you recommend a primer that is specifically formulated to cover water stains on wood surfaces?
Yes, I can definitely recommend a primer that is specifically formulated to cover water stains on wood surfaces. One highly regarded option is the Zinsser Bulls Eye 1-2-3 Water-Based Primer. This primer is known for its excellent stain-blocking capabilities, including water stains on wood. It effectively seals the stain and prevents it from bleeding through the topcoat.
The Zinsser Bulls Eye 1-2-3 Water-Based Primer is easy to apply and dries quickly, allowing you to proceed with your painting or staining project in a timely manner. It also has good adhesion properties, ensuring that your topcoat adheres well to the primed surface.
Before applying the primer, it is recommended to clean the wood surface thoroughly and remove any loose or flaking paint. Additionally, it is important to follow the manufacturer's instructions for proper application and drying times.
Overall, the Zinsser Bulls Eye 1-2-3 Water-Based Primer is a reliable choice for covering water stains on wood surfaces, providing a solid foundation for your finishing project.
Can you suggest a primer that provides a smooth and even finish while effectively covering water stains?
I would recommend using a high-quality stain-blocking primer such as Zinsser Bulls Eye 1-2-3 Primer. This primer is specifically designed to cover water stains and other tough stains effectively. It provides excellent adhesion and creates a smooth and even finish on various surfaces, including walls and ceilings.
Zinsser Bulls Eye 1-2-3 Primer is water-based, making it easy to clean up with soap and water. It dries quickly and has low odor, which is beneficial for indoor projects. Additionally, this primer can be top-coated with both oil-based and latex paints, giving you flexibility in choosing your finish.
Before applying the primer, it is important to properly clean and dry the surface to ensure optimal adhesion. By using Zinsser Bulls Eye 1-2-3 Primer, you can effectively cover water stains and achieve a smooth and flawless finish on your project.
Is there a primer that can effectively cover both water stains and smoke stains?
Yes, there are primers available in the market that can effectively cover both water stains and smoke stains. One such option is a stain-blocking primer. Stain-blocking primers are specifically designed to seal and cover various types of stains, including water stains and smoke stains. These primers are formulated with special ingredients that create a barrier, preventing the stains from bleeding through the topcoat.
When selecting a stain-blocking primer, look for ones that specifically mention their ability to cover water stains and smoke stains on the label. It is also important to choose a primer that is suitable for the surface you are working with, whether it is walls, ceilings, or furniture.
Before applying the primer, it is recommended to clean the surface thoroughly to remove any loose dirt or debris. Depending on the severity of the stains, you may need to apply multiple coats of the primer. Always follow the manufacturer's instructions for the best results.
In case you are uncertain about which primer to choose or need further assistance, it is advisable to consult with a professional at your local paint store. They can provide expert advice and recommend the best primer for your specific needs.
What are the top-rated primers specifically designed for covering water stains on walls?
One of the top-rated primers specifically designed for covering water stains on walls is Zinsser Bulls Eye 1-2-3 Primer. This primer is known for its excellent stain-blocking properties and can effectively cover water stains, as well as other types of stains such as smoke and nicotine. It is water-based, which makes it easy to clean up and has low odor. Another highly recommended primer is Kilz Original Multi-Surface Stain Blocking Interior Oil-Based Primer. This primer is oil-based and provides superior stain-blocking capabilities, making it ideal for covering water stains on walls. It also has excellent adhesion and can be used on various surfaces. Both of these primers have received positive reviews from homeowners and professionals alike for their ability to effectively cover water stains and prevent them from bleeding through the topcoat.
What primer is best for covering water stains on porous surfaces, such as drywall or plaster?
When it comes to covering water stains on porous surfaces like drywall or plaster, using a stain-blocking primer is essential. One of the most recommended options is a shellac-based primer, such as Zinsser BIN Primer. This type of primer is highly effective in sealing water stains and preventing them from bleeding through the topcoat.
Shellac-based primers have excellent adhesion properties, making them suitable for porous surfaces. They create a barrier that blocks the stains and prevents them from resurfacing. Additionally, shellac-based primers dry quickly and have good coverage, which helps save time during the painting process.
Another alternative is an oil-based primer, like Kilz Original Primer. Oil-based primers also provide excellent stain-blocking capabilities and work well on porous surfaces. They create a strong seal that prevents water stains from showing through the topcoat.
In summary, for covering water stains on porous surfaces like drywall or plaster, choosing a shellac-based primer like Zinsser BIN or an oil-based primer such as Kilz Original should yield the best results.
Which primer is most effective at covering dark water stains on ceilings?
When it comes to covering dark water stains on ceilings, the most effective primer to use is an oil-based stain-blocking primer. Oil-based primers have excellent coverage and adhesion properties, making them ideal for hiding water stains. They create a barrier that prevents the stain from bleeding through the paint, ensuring a clean and even finish.
One highly recommended oil-based primer for covering water stains is Kilz Original. It is known for its exceptional stain-blocking capabilities and is specifically designed to cover tough stains like water damage. Another popular option is Zinsser Cover Stain, which also provides excellent coverage and adhesion.
It is important to note that before applying any primer, it is crucial to address the underlying issue that caused the water stains. Repair any leaks or water damage and allow the area to dry thoroughly before applying primer and paint. This will ensure a long-lasting and effective solution to covering dark water stains on ceilings.
Which primer is most recommended for covering water stains in high humidity areas, such as bathrooms or basements?
When it comes to covering water stains in high humidity areas like bathrooms or basements, it is important to choose a primer that is specifically designed for such conditions. One primer that is highly recommended for this purpose is a stain-blocking primer that is mold and mildew resistant. These types of primers are specifically formulated to combat the growth of mold and mildew in high humidity environments.
One popular option is a water-based latex primer that contains an anti-microbial agent. This type of primer not only covers water stains effectively, but also helps prevent the growth of mold and mildew. Another option is an oil-based primer that has similar properties. Both these types of primers have excellent adhesion properties and can be used on a variety of surfaces.
When selecting a primer, it is important to ensure that it is specifically labeled as mold and mildew resistant, as these primers are formulated to withstand high humidity environments. Additionally, it is advisable to choose a primer that is compatible with the type of paint you plan to use on top, to ensure proper adhesion and long-lasting results.
Overall, a stain-blocking primer that is mold and mildew resistant, such as a water-based latex or oil-based primer, would be the most recommended choice for covering water stains in high humidity areas like bathrooms or basements.