Does Kilz Cover Water Stains? (Complete Guide)

Water stains are an eyesore and a constant source of embarrassment for many homeowners. Try explaining that dark splotchy mess on your once-pristine walls or ceilings. 

For most professional painters, Kilz primers are the first choice for covering water stains. A coat of paint is often enough to seal even the most challenging water stains on interior and exterior surfaces. Just avoid using the product on your floors.

But there’s more to the story: Some Kilz primers are better than others. The brand is more effective on some surfaces than others. 

This article will give you more information about which types of water stains Kilz is best for, which product line to try, and how to apply them.

using Kilz primer to cover up water stains on the wall 1

Does Kilz Cover Water Stains on All Surfaces? 

Kilz primers adhere well to many surfaces like drywall, wood, POP ceilings, hardwood, concrete, and even masonry. However, Kilz manufacturers do not recommend using the product on floors. 

According to some users, the primer wears out quickly on floor surfaces with heavy foot traffic. You can increase the longevity of the primer by covering it with a durable topcoat paint. 

How Many Coats of Kilz to Cover Water Stains? 

Kilz primers are designed to block light to severe stains. 

In most cases, just two coats of paint primer can block even tough stains. But some heavy-duty stain blockers like Kilz 2 or Kilz 3 Premium have a thick consistency that covers water stains in one coat. 

Try this simple test if unsure about the number of coats of paint primer to apply: Start by using the preferred number of coats on the stained surface. Wait for it to dry. 

Next, brush a small part of the stained area with a topcoat. Now, watch if the stain bleeds through the topcoat. Is the stain still showing? You will need to apply another coat if the stain is still showing. 

Best Kilz Primers for Covering Water Stains? 

Some Kilz primers are well-formulated to remove tough stains on both interior and exterior surfaces. These heavy-duty primers are perfect for covering water stains on ceilings and walls. Some can even protect floors. 

Let’s explore the top Kilz primers for getting this job done: 

Kilz 3 Premium Interior and Exterior Primer

Kilz 3 Premium is one of the heavy hitters in the primer industry. It is a latex-based primer that’s suitable for covering light stains, moderate stains, and heavy stains with ease. 

Furthermore, it protects against mildew—talk about a two-in-one solution!

 Keep in mind the Kilz primer is thicker than most Kilz primers. A single coat of this product is often enough to cover most water stains. 

Kilz 2 Premium

Kilz 2 Premium is quite similar to the Kilz 2 in function but noticeably less powerful in stain removal. But you might still use it to cover light water stains. It is also an excellent option for killing mildew on any surface. 

Kilz primers are famous for their fast drying rate. So, you can also see the result of your DIY painting project in less time than other primers. 

Often, it dries to the touch within 30 minutes. However, waiting a few hours is advisable before adding another primer coat or a topcoat. 

Step-by-Step Guide for Covering Water Stains with Kilz

water stains on the ceiling

It’s not enough to use the suitable Kilz primer. As a DIYer, you need to employ the correct procedure to seal the stains before using a topcoat. 

For this reason, we’ll explore how to apply it to your ceilings, walls, and floor surfaces. 

Step 1: Get the Necessary Materials

Let’s explore the materials you’ll need for the job. Thankfully, you may have a few of these items in your toolbox or pantry.

First, start with grabbing a can of Kilz 3 Premium or Kilz Original. 

Next, get your gloves, sandpaper, polyethylene tarp, and a brush or roller. Don’t forget to get a ladder to prevent falls while working on the ceiling or high surfaces. 

Use a face mask and eye covering. Some paints have VOCs higher than 500 ppb, which may trigger allergic reactions when inhaled. 

Step 2: Apply Kilz on the Water-Stained Surface

covering water stains with kilz

It’s time to apply Kilz to the affected areas. Keep in mind that there are different techniques for using the primer on distinct surfaces. So, let’s explore these differences:

Applying Kilz Primers to Ceiling Stains 

Here’s what to expect when painting ceilings: the primer may not cover the stain. The “primed” part may end up with a lighter or darker shade than unaffected areas. So, always cover it with a top coat for uniformity. 

But to get a perfect coat of ceiling paint primer before using a topcoat, follow these steps:

  1. Set up your ladder and ensure it’s sturdy enough to support your weight. 
  1. Place a polyethylene tarp on the floor directly below the stained area. 
  1. Lightly sand down the stain. 
  1. Dip the brush or paint roller into the primer can. 
  1. Apply a single coat and wait for at least one hour before adding another layer.
  1. Wait for it to dry before painting with a top coat. 

If you want, you can take this opportunity to prime and add fresh paint to your entire ceiling rather than just the water-stained part.

Applying Kilz Primers to Interior and Exterior Walls 

Sometimes, you’ll find mold and mildew growing on water-stained walls. We advise you to choose a mold-killing, stain-blocking primer. Kilz 3 Premium is the perfect option for this section. 

Next, follow these steps to apply the primer to mold- and water-stained walls:

  1. Sand the affected area to remove molds and mildews growing on the wall. 
  1. Dip a brush into the primer and apply it to the surface. 
  1. Wait for the primer to dry before applying a top coat. 

After you’re done, store the leftover primer according to state or federal safety regulations. 


Kilz primers are great for any paint job where you’re covering water stains, pet stains, nicotine stains, or even crayon marks. Remember to follow these stain blocking steps and share this fantastic journey of self-reliance with other DIYers!