What Causes Paint to Bubble?

Painting a Room? What Causes Paint to Bubble—Answered

There’s more to the art of painting than slapping latex paint to a wall and calling it a day. Nothing is as discouraging as giving your home a fresh coat of paint only to find the walls blistering days – or even months – later.

Paint blisters or bubbles are pockets of fluid that congregate between dried paint causing the paint fil to lift from the underlying surface, which results in an unsightly finish and even marks on the walls. It’s worth noting that bubbling has little to do with the type of paint as it can occur with both oil- and water-based paint. The most ideal way to solve the issue of bubbling paint is to pindown the underlying problem that’s triggering the bubbling in the first place or the problem will continue to recur.

If you’re still asking “what causes paint to bubble?” here’s a few reasons:

Why Causes Paint to Bubble or Blister?

Paint bubbling is as a result of paint losing its adhesion, a quality that helps bind it to the surface beneath, be it a previous coat of paint or substrate. Air- or water-filled bubbles form as the paint loses adhesion and harden in place, resulting in an unsightly surface that you’ll need to fix. It’s not advisable to paint over the bubbles – it’s a short-term solution and eventually the paint will re-bubble. In some cases, the bubbles may deflate or pop on their own and later begin to peel.

Here are some possible reasons why your paint is bubbling:

1. You didn’t start with a clean painting surface

Dust, dirt, and grime can collect on your walls over time and you may have painted over a contaminant and the paint was unable to stick. The most common factors that prevent paint from fully adhering include dirt and moisture concerns. As such, it’s vitally important to clean the surface before applying fresh paint. If you’re cleaning with water, ensure the walls dry completely before applying primer or pint.

2. Moisture on your walls

Excessive moisture in your home can cause water-filled bubbles to form beneath the layer of paint and eventually lead to peeling. This is especially common in damp basements and poorly-ventilated kitchens and bathrooms, or in houses with leaking plumbing where water has traveled from the interior to the exterior wall. What’s more, applying oil-based paint over latex paint exposed to high humidity and moisture can result in bubbles.

3. It was hot and humid when the paint was applied

As with moisture, heat can also lead to bubbling. Except in this case, bubbling isn’t so much a problem of adherence as it is an issue of drying. Painting your exterior walls in direct sunlight may prevent the paint from adhering properly. Same case when painting a room with a lot of heat generating appliances like your living room – the top coat could dry at a faster rate resulting in bubbles.

4. Inadequate preparation

Using the wrong paint, tools, or techniques can also lead to bubbling. It’s best to apply oil-based paint on oil-based paint. However, if you want to use latex paint over oil-based paint because of its many benefits like lower VOCs and faster drying time, you’ll have to make some additional preparations in addition to cleaning the walls.

The key to making paint stick is to actually make the wall a little bit rough and uneven. Use fine-grit sandpaper to remove imperfections and create peaks and valleys that will make the paint stick better. Or you can apply a coat of primer to the smooth surface to help the paint adhere.

How To Fix Paint Bubbling

To fix bubbling paint, you must first eliminate the underlying cause. For instance, if high humidity is the culprit you can use a dehumidifier or fan to dissipate excess moisture as the paint dries. Additionally, make sure your walls are clean and free of contaminants before starting the paint job.

Once you’ve identified and adjusted for the cause of blistering, it’s time to remove the blemishes altogether. There are three steps to repairing bubbled paint:

  1. Scraping off the damaged paint with a putty knife
  2. Preparing the surface for a new coat
  3. Repainting the affected area

At the preparation stage, you may need to caulk any holes or cracks in the surface with a patching compound. Apply the paint to a clean, dry surface and paint in the appropriate conditions.

All in all, painting is a surprisingly technical job that requires a professional touch even for a job as seemingly simple as bathroom painting. Working with a contractor offering home painting services could be the trick to getting it right the first time.

If you’re looking for home painters in St. Pete, Tampa Bay Painting Company offers interior painting services that can be tailored to your needs and preferences. Contact us to get started on the journey to upgrading your home.