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I've Got Paint Bubbling On Exterior Walls: How Can I Solve It?


Having the exterior of your home painted is a significant project to undertake, and it can be very costly as well. So, if you notice just a few short weeks after the paint has been applied that it is beginning to bubble and blister, you will be terribly disappointed.

There are a number of reasons why paint will bubble in this way and it is possible to prevent it with the right preparation. Or you can simply choose a specialised paint that will avoid this issue completely, as the following article reveals…

Why Does Paint Bubble?

Many types of paint will bubble, but it is more likely to occur with latex or acrylic type paints. These are often used on exterior walls, as they are waterproof, making this a much more common problem for outside walls than indoors.

The issue is caused by the paint starting to lose its adhesion to the wall surface, or the previous paint layers. There are two main reasons why paint will start to bubble or blister:

● The paint has been applied to a damp or wet surface. This is by far the most common reason for the blistering of paint, and can also happen when the paint is exposed to wet weather before it has dried completely. Moisture caused by high humidity can also have a similar effect.
● The paint has been applied to a dirty surface. As the paint dries, the surface of the paint is pulled up. If it hasn’t adhered to the wall properly, the paint will bubble rather than drying flat. The use of a primer on clean walls can help.

The main issue, and the one that occurs with both of these causes, is that a chemical reaction takes place during the drying process. The top layer of paint dries first, forming a barrier that prevents the solvents within the mix from escaping.

The solvents begin to vaporise and expand, putting pressure on the paint to force it away from the surface, consequently creating a bubble.

This is much more likely to happen during warm weather. If the wall is damp and cool, and the surface of the paint is very warm (in direct sunlight), the drying process is uneven, and the side facing the sun will dry before the lower layers that are against the cool, wet wall.

Put simply, the more mineral spirit that is in the paint the quicker it will start to dry.


Most homeowners follow a step by step process to remove paint bubbles, involving scraping the bubbles, sanding the area, and then priming and applying new paint

Why Paint Bubbles Are Far From Ideal

You may think that you can live with the way that your paint job looks, despite the bubbles. In many cases, the effect is not too noticeable, and the bubbles are concentrated in a small area. However, leaving them is never a good thing to do.

The paint bubbles are likely to pop on their own, and will expose the wood underneath. This is the perfect spot for water to sit against the side of your home, and this moisture could lead to the rest of the paint being affected – not to mention your interior walls if that water was to seep into the interior cavity.

How Can I Get Rid Of Paint Bubbles On My Walls?

Generally speaking, most homeowners follow a step by step process to remove paint bubbles. This usually involves scraping the paint bubbles, sanding the area, cleaning off any dust and dirt that occurred during sanding, before priming and painting.

But are there any easier methods of bursting those bubbles?

In short, yes-but they are best attempted by those with a decent amount of D.I.Y experience behind them.

The first alternative method is to simply do nothing. Yes, you heard that right! Confused? Let us explain...

In some cases, as the paint cures, the problem actually resolves itself. Of course, a good deal of patience is necessary if you adopt this approach. Give it a little time, and if the bubbles paint problem seems to be clearing, it's all well and good. If not, then a different tactic should be deployed...

The second alternative method involves ironing the bubbles out of the wall. As crazy as this sounds, the science behind it is simple: turn on an iron, let it get hot, and press it against the wall for a period of 30 seconds. The heat of the iron will help to soften the paint. Remove the iron, and then once the area is cool, press out the bubbles with your fingers. Sorted!


For walls that are directly in the path of sunlight, a cool day is the best for painting. And if rain is forecast? Save your project for another day!

Fixing Blistering Paint: Why You Should Start From Scratch

There really is only one way to fix paint that has bubbles in it – start afresh. The bubbled area needs to be sanded back, the exposed spot needs to be completely dried out, and the areas in question fully repainted.

This may cause a patchy effect that can be disappointing. You may even need to sand back, and repaint the entire wall to ensure an even finish.

Make sure you follow the rules above to prevent the same issue happening again.

8 Top Tips To Avoid Bubbling Paint Problems For Good

● Always thoroughly prepare the surface before beginning to paint. This means removing all dirt, peeling or cracked paint and sanding back to bare wood if necessary. If you use a pressure washer to remove old paint, you must wait for the walls to dry completely.
● Use a primer on the walls if required to achieve a smooth surface for adhesion. Ensure that the primer is designed for use with the paint of your choice.
● Choose a paint that is low in mineral spirit. Or go for a low chemical based paint that will have a slower drying time.
● Try to paint walls that are entirely dry, and never within 4 hours of rain. In fact, it may take up to 8 hours of clear weather for the walls to dry after rain. This can be sped up by using blowers and heaters.
● Always avoid painting if it may rain later in the day. Water on the newly applied paint will affect drying times-and prove detrimental to the final results.
● Choose a cool day to paint those walls that are directly in the path of sunlight.
● Try thinning down your paint with a paint conditioner to slow down the rate at which it dries. Use this method only if you cannot avoid hot weather and direct sunlight.
● If walls are damp, or there is a moisture issue, correct this before doing any painting at all.


Unlike normal paints, which can be prone to flaking and bubbles, hydrophobic coatings won't blister over time, as they've been formulated with breathability in mind.

Moral Of The Story? Choose A Specialised Paint

With moisture being the worst culprit when it comes to ruined paint work, it is clear that using a paint or coating on your exterior walls that is designed to repel water is a great start.

These hydrophobic paints are designed to prevent water getting onto the wall surface, and actively repel water and dirt as well. They can protect the masonry against inclement weather, thereby preventing issues with water making its way into the home.

An exterior wall that has any small holes or cracks will soon have a much bigger problem. The water can make its way into these openings, and if it freezes, it can expand, making the cracks even larger.

Further problems come from the water saturating the interior cavity wall insulation, or making its way onto the interior walls where mould can grow. Fixing any water ingress problems should always be a priority.

A hydrophobic paint is the perfect solution. Used in place of normal paint, this coating will not blister, as it is designed to breathe. It allows moisture that is already in the wall to escape, while providing a barrier to new water making its way inside the wall. This makes it perfect for all homes.

If you prefer to keep the look of your brickwork, you can also choose to use a clear coating that offers the same protection, but maintains the traditional look and feel of your brickwork.

The bubbling that happens on your paint work can be distressing, and can make it feel like the hard work of preparing and painting your exterior walls is a waste of time.

But by using the right paints, you can prevent this from happening in the first place and create an environment that protects your walls from an future issues associated with water.

Ready to take your exterior renovation project to the next level? Properla paint offers premium property protection, without compromising external aesthetics. Take the first step to achieving a fabulous new frontage today, by calling 0800 1700 636, or simply clicking the button below!

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