Best Mold Killing Primer


Molds, algae, mildew, and other fungal organisms pose a significant threat to wooden appliances’ durability. These inhibitors slowly weaken the material by interfering with the grain arrangement and exposing the wood’s interior to limiting factors such as water, temperature, and moisture. However, you can use the best mold killing primers as the remedy to this situation. 


These products have an excellent composition of fungal repellent ingredients that kill the existing molds and prevent them from growing on the finished painting. Additionally, they also have a high adhesion nature that enables you to effectively prime on previously painted surfaces and surfaces with other minor markings.


You also need to make the application in the shortest time possible to get enough painting time- Therefore, the primers dry to touch after a short period. Furthermore, you also have numerous application methods to choose from depending on your preference(roller, brush, or spray-on).


However, due to the competitive market today, the quality of these products has gone below average. Therefore, I have taken the time to do all the necessary research and evaluated the outstanding primers and the guide to see you through the next shopping.


Read on to find out.


  • Rust-Oleum 2004 Zinsser Bulls Eye 1-2-3 Primer


There is no doubt as to why Rust-Oleum 2004 Zinsser Bulls Eye 1-2-3 Primer is among the best mold killing primers. This outstanding product acts excellently as wood, concrete, glass, plaster, metal, or even a tile primer.


The 2004 Zinsser eliminates the need to sand since it can stick to any type of surface. Besides that, you can conveniently use this product on new metals, thanks to the incorporated rust inhibitor and the water-based formula.


As a mold killing primer, its water-based nature prevents the mildew growth, the formation of blisters, and peeling- Generally, this capability protects the wood from rotting, increasing its durability. The merchandise also has an extensive area coverage of approximately 100 square feet per quart.


Summary of the key features

  • The primer incorporates rich ingredients that make it ideal for high PH surfaces.
  • It has a water-based formula that can resist mildew growth and other prevailing factors like blistering and peeling.
  • The product also has rust inhibitors, thereby making it suitable for use even on new metal surfaces.
  • You can use this primer on any kind of interior or exterior surface without sanding.
  • It also has comprehensive area coverage and dries in only one hour without using any top-coat.



  • Mold and mildew resistant film.
  • Blocks stains.
  • Sticks to any surface without sanding.
  • Ideal for dark top-coat colors.
  • It works effectively with any oil paint or latex paint.
  • The product also stipulates an adequate adhesion.
  • Rust resistant.
  • Excellent flow and leveling.
  • Low odor.



  • The product covers only 100 square feet per quart.


  • Rust-Oleum 276087 Mold Killing Primer Quart


This product has some similarities compared to its predecessor, the Rust-Oleum 2004 Zinsser Bulls Eye 1-2-3 Primer. First, the 276087 mold killing primer does not allow any effect from biological factors, including the growth of mold, algae, or mildew.


Additionally, as a water-based commodity, it has an efficiency that provides an oil-based primer’s performance. You can also use either a brush or roller to apply to any surface. However, you can employ a spray-can for hard-to-reach areas.


This flexible acrylic primer has an exceptional adhesion property, making it ideal for use on any surface without the need to top-coat. It also saves your time since it only dries in one-hour time with a great flow and leveling.


Summary of the key features

  • You can use this product on drywalls, concrete, sidings, or even tiles, taking advantage of its adhesion capability.
  • This merchandise’s overall finish seals all the tannin bleeds, graffiti, stains, and resists molds, algae, and mildew.  
  • It’s also suitable for application on new metals and alkaline surfaces since it’s rust-resistant.
  • The product also has a breathable and flexible nature that enables it to resist moisture effects such as blistering and peeling.
  • You can also conveniently reach the hard to spray areas using the aerosol spray paint formula.
  • It’s suitable for any surface and covers up to 100 square feet per quart.



  • Water-based formula.
  • Rust resistant.
  • Stain blocker.
  • You can use any top-coat.
  • It provides an oil-based performance.
  • Low odor.
  • It’s ideal for a variety of surfaces.
  • You can effectively apply to the hard-to-reach areas.
  • It seals uniformly.



  • It takes up to 1-hour to dry.


  • KILZ 2 Multi-Surface Stain Blocking Interior


Are you looking for the best mold killing primer that makes paint stick better to any surface type? Worry not because the KILZ 2 Multi-Surface Stain Blocking Interior ensures that the paint color is more authentic and saves on cost by enabling you to use less paint.


This incredible product also provides a barrier to mild and medium staining from grease, pencil, water, ink, felt maker, and many more. Additionally, the primer can fully cover previously painted surfaces and also stipulates high adhesion for new paints.


To obtain a better finish, top-coat with latex or oil-based paints. Furthermore, you can effectively use this primer on all interior or exterior surfaces- This includes bricks, well-prepared glossy surfaces, painted metal, drywall, Mansory, paneling, plaster, stucco, wood.


Unlike other ordinary primers, KILZ 2 dries in only 30-minutes letting the surface ready for recoating in only one hour. However, you should ensure that the wood surface has no dust, grease, rust, mold, chalk, mold, or any signs of peeling paints.


Summary of the key features

  • The product comes in a 1-gallon container that you can appropriately use to an area ranging between 300 and 400 square feet per with each gallon.
  • This primer takes a precise time of only 30-minutes to completely dry.
  • Its adhesion properties enable you to use less paint since it allows the paint to stick regardless of the surface.
  • You can use it on previously painted surfaces as it can cover paints, chalks, pencil marks, and even graffiti.
  • This product also provides a mildew and mold resistant finish.



  • It’s a medium and light level stain blocker.
  • Drys quickly.
  • Enables paint to stick firmly.
  • This primer hides the previous paints.
  • Easy to apply.
  • It seals porous surfaces.
  • It also stipulates stronger adhesion for new paints.



  • You should use it on properly prepared surfaces.
  • It requires a top-coat.


  • Rust-Oleum 276087 White Zinsser Mold Killing Primer


Meet the Rust-Oleum 276087 White Zinsser Mold Killing Primer, which can kill even the existing mold, mildew, odor-causing bacteria, and other fungal organisms. On top of that, this commodity also features an EPA registered antimicrobial that prevents any fungal organisms’ growth on the paint film. 


However, when spreading to a surface with stains caused by water leaks, it’s recommended that you leave the primer to dry, then apply a Zinsser stain-blocking primer. This product also binds chalky siding, metal, and masonry.


You can effectively use the 276087 woodworking primer for under wall covering- since it provides a covering coat for fungal stains and residual microbiological organisms.


Summary of the key features

  • The product integrates a water-based fungicidal protective coating that you can conveniently use to paint over existing mold, fungi, mildew, and other fungal organisms.
  • It further characterizes an EPA registered antimicrobial that blocks molds and algae from growing on the paint surfaces.
  • You can also effectively use this product on water leak stains by allowing it to dry then apply a Zinsser stain-blocking primer.



  • You can directly paint over existing molds.
  • Kills and prevents the growth of the fungal organism.
  • It covers fungal stains.
  • You can use it with a Zinsser stain-blocking timer.
  • It covers a wide area.
  • Rust-resistant.



  • The product doesn’t work well on stains caused by water leaks. 


  • INSL-X AQ040009A-01 Aqua Lock Plus


For blocking household stains and sealing of porous surfaces, choose the INSL-X AQ040009A-01 Aqua Lock Plus. You can get this versatile product in either white or back color, depending on your preference.


Moreover, this primer offers a multipurpose capability with its 100% acrylic sealing property. Therefore, you can use it for any interior or exterior purposes. The commodity also provides excellent adhesion regardless of the surface of the application.


The AQ040009A-01 wood killing stain also guarantees superior sealing and coverage qualities ranging from 300 to 400 square feet converge per gallon. It also has a low VOC(Volatile Organic Compounds) and takes as little as 30 minutes to completely dry. However, you have to top coat after one hour.


Summary of the key features

  • The primer comes with an instructional guide on the label that helps you know all the details required for proper preparations and the application tips.
  • You can either use a ¾” nap roller for porous surfaces and a paintbrush for the areas that are tough to roll.
  • The product works best on previously painted surfaces since it promotes adhesion of the finish coat.
  • This commodity can seal stains to prevent possible bleeding through the final well-leveled coat.
  • Its versatility provides a magnificent base coat for both oil-based and latex finish coatings.
  • The primer comes well-packed in a 1-gallon tank with a comprehensive area coverage of up to 300 to 400 square feet per gallon.



  • 100% acrylic primer-sealer.
  • It provides an efficient base coat.
  • Superior sealing.
  • Low VOC.
  • It’s suitable for numerous surfaces.
  • It’s available in black or white color.
  • Durable.
  • You can apply using a roller or a paintbrush.



  • The ambient temperature should be above 10-degrees Celsius and below 32-degrees Celsius for a useful application.


  • Rust-Oleum Corporation 01008 Primer Spray


Contrary to other best mold killing primers, the Rust-Oleum Corporation 01008 Primer comes in an elementary to use spray-can- This ensures that you can conveniently reach to the confined areas.


Additionally, this product easily sticks to any surface without sanding, enabling you to use it for interior and spot exterior surfaces effectively. The 01008 Primer Spray offers a lightning-fast drying allowing you to recoat in only 45-minutes.


This merchandise also leaves no stain behind by ensuring that it completely covers all the available residue from vertical and horizontal positions. Besides, it also permanently blocks all the wood knots and sap streaks.


Summary of the key features

  • The product has a strong adhesion capability that enables it to stick permanently on any surface without sanding.
  • It seals all kinds of knots, streaks, odors, and even stain, leaving behind a well-finished surface ready for painting.
  • It’s the only mold killing primer that comes in a convenient spray can for ease of use.
  • This commodity has a shellac-based formula that enables it to dry quickly and firmly stick on the application surface.



  • Permanently blocks stains, wood knots, and odors.
  • Fast-drying.
  • It’s the most fantastic stain sealer.
  • The product is suitable for spot exterior and interior use.
  • Recoating is only after 45 minutes.
  • It comes in an easy to use spray-can.
  • This primer resists mildew, algae, and mold.


  • You can only apply using the spraying method.


  • KILZ L204511 Kitchen & Bath Interior Latex Primer


Unfortunately, the KILZ L204511 Kitchen & Bath Interior Latex Primer is only ideal for interior, residential surfaces in high-humidity, temperature, and moisture environments- This includes bathrooms, kitchens, powder, and laundry rooms. 


However, this does not hinder it from its primary chore to prevent the growth of fungi, mold, and any other fungal organisms that may get confined between the paint and the primer.  This product has many functionalities, including blocking flight to medium stains, sealing porous surfaces, and also offers high hide for various color amendments.


Furthermore, the KILZ L204511 primer proffers a well-finished surface that you can effortlessly clean using soap and water. Since it dries very quickly, you can use this product on drywall, wood, painted metal, brick, and many other places.


Summary of the key features

  • This unique primer provides an improvised mildew-resistant film that prevents the growth of most of the fungal organisms.
  • It has enhanced pigments that block light to medium stains and seals the porous surfaces to prevent wood rot.
  • The product has high adhesion properties that offer a sound anchor for paints. 
  • It’s for high humidity, temperature, and moisture environments like the bathroom, kitchen, and laundry rooms.
  • This item also has an extended area coverage between 30 and 400 square feet, which depends on the porosity, texture, and application method.
  • You can use a brush or a spray-on with a pressure between 2500 to 3200 psi.



  • It blocks most of the household stains.
  • The product has a low chemical emission.
  • Ideal for interior use.
  • Easy to clean with soap and water.
  • It dries quickly.
  • Offers hide for color changes.
  • It also provides a smooth and level finish.
  • This item resists mildew, algae, mold, and other organic defects.
  • Easy to apply.
  • It does not require thinning.



  • Ideal for interior use only.


  • Zinsser 276049 Mold Killing Primer Gal


Just as its name suggests, the Zinsser 276049 Mold Killing Primer Gal does not give any chance to existing molds and those that might grow lately. Gratitude to its EPA registered fungicidal protective coat that equally leaves a smooth and well-finished surface.


This product also entails a water-based formula that facilitates the fungicidal protective coating, which you can conveniently use under any coat. Additionally, this feature renders it suitable for use with ZI NSSER perma-white.


The Zinsser 276049 primer dries after only 30-minutes making it ready for top coating in one hour. However, if you want it to provide optimal protection against all the inhibiting factors, ensure that you top-coat within 72-hours of application.


This item further gives you the freedom and comfort of application, since you can choose to use ZINSSER mold blocking primer spray for all your petite projects. Moreover, it comes in different sizes, including 1-gallon, 5-gallons, and quart.


Summary of the key features

  • The product incorporates a water-based EPA registered fungicidal protective coat that kills all the existing molds while inhibiting their growth.
  • You can directly paint over the prevailing mildew and molds without the need to extensively clean the surface.
  • With the vast advantages, you can use this item for industrial, commercial, and residential applications, including wall cavities, window frames, bathrooms, and many more.
  • This primer also gives you the option of choosing optimal protection by top coating within 72-hours of application.
  • It also comes with an instructional label on the side for guides with unstable structural surfaces.



  • It’s ideal for both small and big projects.
  • Dries in only 30-minutes.
  • You can use it to bind masonry, metals, and chalky sidings.
  • Sufficient for under wall covering.
  • Available in various sizes.
  • It offers optimal protection.
  • It kills existing molds and mildews.



  • The applied surface takes about 30-minutes to dry completely.


Best Mold Killing Primer Buyers’ Guide


Wood rot and peeling has always been a significant challenge to most of the wooden appliances. It results from the growth of mold and other fungal organisms that end up weakening the entire structure.


This article has highlighted all the best mold killing primers. However, I find it essential to facilitate a comprehensive guide for picking out the outstanding primer and the reasons for buying.


Reasons Why You Need To Buy A Mold Killing Primer


  • Fungal-resistant. This product has efficient pigments that contain the growth of molds, algae, mildew, and other fungal organisms that cause wood rot.
  • Available in various colors and sizes. Most of these products come as either black or white and also vary in sizes. Therefore, you can choose the color and quantity depending on your preference.
  • Numerous application methods. You can effortlessly apply using a paintbrush, roller, or even a spray-on.
  • Easy to clean. You don’t need to use chemicals for cleaning purposes. Instead, make use of clean water and soap for elementary cleaning.
  • No sanding. The products also eliminate the need to sand between the surfaces before application.
  • Dries quickly. Most of these primers take at least 30-minutes to dry entirely and up to 1-hour for recoating.
  • High adhesion. The products also have an efficient adhesive capability that facilitates easy painting.
  • Rust-resistant. Some of these items have rust inhibitors that enable you to use them with new metals effectively.
  • Wide coverage. You can conveniently use these products on comprehensive area coverage. However, this depends on the texture, porosity, and the method of application.


Factors To Consider When Buying The Best Mold Killing Primer


  • Application Method


The application method matters a lot since some places tend to be hard to reach, such as the confined areas. 

The commonly used are the roller for delicate surfaces and paintbrushes for irregular or rough surfaces. 


However, you can also use the spray-on method. For instance, a product like the Rust-Oleum Corporation 01008 Primer Spray comes in a convenient spray-can that is effortless to use.


  • Composition 


The composition of these products determines the overall performance on different surfaces. It also provides a protective film that prevents the growth of fungal organisms that causes wood rot. The ideal composition can either be oil-based, water-based, or shellac-based, as seen in Rust-Oleum Corporation 01008 Primer Spray.


  • Projects size.


Woefully, these primers come in different sizes, meaning that you need to choose the one that will comfortably fit your project’s demands. Besides, you will also find on the instructional guide the possible coverage area of the product well-labeled at the side.


  • Application rules


These products differ in the application requirements. For example, before applying some of the primers, you have to clean the application area for any peels or molds.


However, for some products such as the Zinsser 276049 Mold Killing Primer Gal, there is no need for pre-cleaning since you can effectively apply on pre-grown mold, mildew, or algae. 




There is no uncertainty that you will always require a primer, especially when using the type of paints that require priming. These excellent products guarantee you adequate adhesion to any surface while killing and preventing the growth of molds. 


Additionally, they prevent other inhibiting factors and leave a smooth and well-leveled surface- Not forgetting that you can also use them on previously painted surfaces. Even so, I choose the best mold, killing primers as Rust-Oleum 2004 Zinsser Bulls Eye 1-2-3 Primer. You can use this magnificent product even on growing molds and numerous surfaces, among other exceptional features.

However, you have this article to refer to when choosing your personal best product, depending on your project’s demand.

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Tyron Otieno

Tyron is an avid woodworker and writer. He founded this website to help other woodworkers, whether hobbyists or professionals by sharing his knowledge and experiencie after a decade of woodworking.