Why Paint Bubbles and How to Fix It?

Sometimes when you apply paint to your walls, you get a bunch of tiny bubbles that pop up. It is a common issue, ruining many interiors and exterior paint jobs, and is an endless source of frustration for homeowners and do-it-yourselfers.

Learn how to fix bubbles under the paint and prevent them from forming.


What causes paint to bubble up or blister?

There’s nothing worse than finishing off a very costly and labor-intensive paint job, only to discover hours, or even months, later, paint bubbling and peeling off the wall.The main cause of bubbling is the poor condition of the underlying surface to which the paint is applied. The paint fails to adhere or “stick” to the surface, causing it to pull away once dried. Dirt and moisture may accumulate in the bubbles, causing them to peel over time.

The following are the most common causes of bubbling.


Water helps prevent the paint from drying out. When water drips or leaks from plumbing problems in the bathroom, like leaking pipes, for example, this can cause water-filled bubbles in the paint


High humidity

It’s high humidity if your house has a poorly ventilated attic. Excess moisture is a problem for painting. When you have too much moisture, it makes the paint get soft and slippery

Excess moisture from outside the paint film will become a vapor in hot weather. Because the vapor can’t escape, it will begin to form bubbles under the paint.

In an internal environment, the temperature is often lower than in the external environment, so the air is usually wetter. Especially in rooms like kitchens, bathrooms, and basements.

Improper surface protection

You need to properly prepare the surface before starting any painting project. It should be thoroughly cleaned of any surface dirt, sanded, and completely dried. It’s especially important to put a coat of primer under a coat of topcoat. If the primer’s main job is to provide adhesion between the paint and the surface, then it’s important that it lasts as long.

High Temperature

If the temperatures are too high, the paint may dry out before it has time to set and bond to the surface it’s painting on. When you are painting it’s best to keep the temperature at about 20°C for the next 48 hours. Whether you’re using latex (water-based) or acrylic paints, the ideal temperature for these types of paint should be between 10° and 29° C. To protect your skin, you should stay out of the sun when possible. Sunlight causes surfaces to be up to 10° to 20° warmer.


Using the wrong paint

Oil and water don’t mix. Paint is very hard to mix. When you apply latex or water-based (latex) paint over oil-based paint, the latex paint will not stick to the oil-based paint, and vice versa. This causes lots of bubbling and peeling and an extremely unprofessional job.

How to prevent bubbling or peeling paint

It is easier to fix a leaky faucet in the beginning than when it becomes a recurring problem. So before you start painting, thoroughly prepare the surface you’re painting on. We recommend the following steps.

Prepare the area

You can clean the area with a sponge dipped in water and detergent to loosen any surface dirt and remove stains.

Wet the area well with warm water, and use a clean, fresh rag to remove any remaining moisture.

Repair surface holes and cracks

Fill in any visible holes or indentations on the surface using putty and a putty knife. Smooth it down completely, then use fine-grit sandpaper to remove any roughness in the

Add a primer

When your house needs painting, a primer will ensure that the paint sticks to the wall. It keeps the paint from scratching by acting as a protective coating to the surface material.

When painting over oil-based paint with latex paint, using a primer will help to ensure a better bond between the two different types of paint.

It’s recommended that you use a primer before applying paint to new wall surfaces such as plasterboard or wood to improve the ability of the paint to stick to the surface.

Note: primer is not the same as paint.

Let the primer dry completely before adding paint. The main differences between them are that primers contain chemicals to enable the paint to stick to it, while paint contains color pigments that provide the color and other materials that provide durability.


Slowly mix the paint. Avoid stirring for too long, as this will create air bubbles in the paint.

Start off using a roller brush, and slowly and gently apply the paint. Slow down if you see any air bubbles.

If you are painting over narrow or smaller surfaces, use the right-size paintbrush and apply the paint in even strokes.


How to fix paint bubbles

Don’t make any repairs until you’re sure the paint has dried. The paint may take a while to dry. Once it’s dry, it will stay that way for a long time. Make sure you have drop cloths on the floor and that you are wearing a mask and goggles when handling dry paint, and that the room is well ventilated.

It’s important to take the proper precautions when removing old paint. Old paint contains lead, which is hazardous if inhaled or swallowed. Professional painters should use proper protective equipment, such as a properly fitted respirator or a good quality mask from a reputable supplier that meets Canadian standards.

Equipment is important, especially if you’re a professional tradesman or contractor. When buying equipment for the job, make sure it’s appropriate to the job and suitable to use in the way that you’ll need to.


Remove blisters by scraping and sanding

A good place to start is to scrape away the old paint with a putty knife. Keep your paint brushes clean and well-maintained. Don’t let paint shavings build up around

Sanding an uneven surface may be necessary to smooth it down.

Remove the source of moisture

Make sure all of the sources of moisture are removed from the bubble bath to prevent it from bubbling. There’s a good chance that you may have to call a plumber if there are any signs of water leakage.

Proper ventilation helps to reduce the humidity. Install vents and exhaust fans to bring in the fresh air.

Make sure the room temperature is between 7° to 32°C if using oil-based paint, and between 10° to 29°C if using water-based (latex) paint, and don’t paint during the day when outside.

The professional results you want will take effort, time, and hard work. Book a free, consultation with us, and let us help you get the results you want without you needing to lift a finger.

By: Royal Painting Edmonton. (Painters Edmonton)

Painters Edmonton
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