How to Fix and Prevent Bubbling Paint Like a Pro

Painting is a very satisfying home improvement task. In a few hours, you can change the entire look and feel a room. However, as with all DIY projects, it’s not always as easy as it seems. You can avoid a lot of problems by following our how-to painting guide. Some problems, however, don’t show up until after the paint has dried. Bubbling paint is one of them, and it’s a perfectionist’s nightmare.

Paint bubbling, or blistering, is one of those pesky unforeseen issues that can, ahem, pop up a few hours after you put down your brush or even years later, depending on the cause. The fix might be as simple as scraping the blister off, patching the area, sanding it smooth, and repainting. Most likely, though, you’ll need to do some investigating to figure out what happened and ensure there isn’t a bigger problem lurking, like water damage or a faulty foundation.

The most likely culprit for paint bubbling on an interior wall is moisture. Excess moisture causes paint to lose its adhesion, pulling away from the drywall and creating the uneven air pockets, or bubbles, you see. That’s why bubbling paint is common in kitchens and bathrooms, where condensation builds up rapidly. If you see it in another room, it could be an indicator of a leak coming from the plumbing or air-conditioning systems or the roof. Prepping your walls inadequately or using the wrong paint or primer can cause cosmetic paint bubbling too—this usually looks like a crop of smaller bubbles.

You need to address the root cause of paint bubbling to prevent further damage to your home. Once you’ve done that, it’s usually pretty easy to patch up your wall and make the paint look smooth again. Below, we’ll walk you through various scenarios and solutions for solving unsightly bubbling paint issues—and explain how to prevent it next time.

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Bubbling Paint Causes

From insufficient prep work to poor conditions, there are a few common reasons why you have paint bubbles on your home’s interior or exterior walls.

The Walls Were/Are Damp.

The most common reason for paint bubbling, as we mentioned above, is too much moisture exposure, resulting in a loss of adhesion. When moisture gets trapped in between paint layers, air pockets form where the paint releases from the wall. Moisture could be coming from humidity in the room, through poorly constructed drywall, from a leak, or through an external crack in the wall. You need fix any leaks before moving on to paint repair.

You Painted When It Was Too Hot.

Temperatures over 85 degrees can cause paint to dry unevenly, and that can lead to paint bubbling. It’s ideal to paint when it’s between 50 and 85 degrees.

You Didn’t Clean the Walls First.

If you didn’t wipe down the walls properly before painting, grease and dirt could be the cause of bubbling. Paint can’t fully adhere to a wall that’s greasy, resulting in a bubbled appearance.

You Didn’t Prime the Walls.

Primer is important whether you’re starting with new walls or covering existing paint. It ensures the paint can grip the surface evenly and consistently.

You Used the Wrong Kind of Paint.

Paint bubbling can happen when you use a different type of paint than what’s already on the wall. Oil- and latex-based paints can’t go on top of each other; the compounds don’t bind, which means you’ll get air bubbles in the top layer of paint.

You Painted Over Wet Paint or Primer.

Not waiting long enough in between coats can also result in “bubbly” paint. Again, moisture is the enemy here. Wait until primed and painted walls are fully dry before applying the next coat.

You Used the Wrong Roller Cover.

All paint brushes and roller covers aren’t the same. They’re designed to apply paint evenly to texture surfaces, from the smoothest to the roughest. It’s important to choose the correct material and nap size for your walls. You want to use a roller and a roller cover for most walls; 3/8 inch is probably best unless you’re working with fresh drywall. Painting tools company Purdy has a roller cover nap guide to help you choose the correct size for your project.

You Stirred the Paint Too Long or Too Fast.

This is a little like baking—you don’t want to overmix paint. It introduces air bubbles into the paint that can show up on your walls. Mix it slowly and keep it brief.

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How to Fix Bubbling Paint

If the cause is surface-level—not the result of a crack in the wall and drywall—begin by scraping off the bubbled paint. Sand it down to create a smooth surface for primer, then fill any holes and cracks with a patching compound. Let the compound dry overnight, then sand again gently with fine-grit sand paper. Clean the area after sanding, apply a primer, allow it to dry completely, then repaint.

roller to wall

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How to Prevent Paint From Bubbling

Follow these tips to get smooth results next time.

  • Look for cracks. Cracks near windows and doorframes could be letting moisture in and wreaking havoc inside the wall. This is a common cause of damage to drywall and framing.
  • Watch the weather. Try not to paint on an extremely hot day because the heat can cause paint to dry unevenly, resulting in bubbling. Similarly, avoid painting in high humidity so that moisture doesn’t get trapped in between paint layers. If you’re painting a bathroom, completely finish painting the room and allow the paint to dry before showering or running a bath.
  • Check the humidity. If excess moisture is a constant problem where you live, you may need to run a dehumidifier in the space you’re painting as you work and while the paint dries to prevent paint bubbling.
  • Prep the walls before painting. Remove dirt, dust, and grease with a rag and soapy water. Let the walls dry completely before applying primer and between every coat.
  • Use primer. Primer lays the perfect foundation for paint. It works as a sealant to help the paint bind better to the wall and creates a smooth surface for you to apply it to.
  • Allow ample time for drying in between coats. If you live in a humid climate, you may have to wait a few days for primer and paint to dry fully before you lay down the next cpat. Be patient! It’ll pay off in the long run.
  • Watch the weather. Try not to paint on an extremely hot day because the heat can cause paint to dry unevenly, resulting in bubbling. Similarly, avoid painting in high humidity so that moisture doesn’t get trapped in between paint layers. If you’re painting a bathroom, completely finish painting the room and allow the paint to dry before showering or running a bath.