The 6 Biggest Problems With Concrete Floor Paint

Painting a concrete floor can open up a range of problems. Often the paint goes on fine but then issues quickly develop, with visible damage appearing and a repaint required after as little as 12 months. Sometimes the issue lies with the paint itself, but more often than not, the root of the issue lies with inadequate surface preparation or the incorrect application method. Below are some of the biggest problems with concrete floors and our recommended solutions.

1) Blisters

Blisters appearing on the surface are one of the biggest challenges with concrete floor paint. These blisters eventually pop, causing large areas of the coating to peel away. The reason for blistering is moisture trapped below the surface of the paint. .

Concrete is a porous material that contains many air bubbles as it sets. This allows moisture or water vapour to seep into the surface and become trapped, working its way back to the surface over time. A concrete floor can hold a reasonably high volume of water while still looking and feeling dry to the touch. Blisters occur when the moisture evaporates out of the microscopic pores within the concrete. The floor paint hinders the water from re-joining the atmosphere as vapour, and instead causes blisters underneath the paint.

The solution? Unfortunately, by the time blisters appear, there isn’t much you can do short of patching up or repainting the floor. However, you can minimise the chance of blisters appearing by ensuring your concrete is fully dry before applying your paint. Don't paint an outdoor concrete floor for several days after rain.

2) Poor Adhesion

It is fairly common for a paint coating to start peeling or blistering within days of application. This usually comes down to poor surface preparation. A poured concrete floor is not a smooth surface but contains thousands of microscopic pits, cracks, and valleys. This can lead to paint pooling in some areas while being spread too thinly in others. The lightly painted areas wear out quickly, while paint that accumulates in cracks and valleys often doesn't dry properly and ends up flaking off in clumps. Poor adhesion can also result from an adverse chemical reaction between the paint and soluble salts leaching out from the concrete. Avoid this issue by ensuring that concrete floors are thoroughly sanded, cleaned and dried before attempting to paint.

4) Peeling

Peeling describes when large areas of floor paint come loose from the concrete undersurface and literally peel away, revealing the substrate beneath. Once peeling occurs, the only solution is to strip away the old surface and apply a new coat. The causes of peeling are – similar to blistering – surface moisture and poor preparation.

5) Contamination

Sometimes a coating of floor paint fails to adhere or dry properly due to contamination. This typically happens when the paint picks up some kind of grease, dirt, or oil from the floor surface due to inadequate cleaning – which then causes an adverse chemical reaction. It is imperative to clean a concrete surface thoroughly before painting, preferably using a jet wash, Acid Etch and or mechanical abrasion depending on the severity of the contamination.

Download Our Free Floor Painting Guide

Most problems with concrete floor paint can be avoided through the correct surface preparation, painting techniques, and the right choice of materials. This isn't as difficult as it sounds, and at TA Paints, we supply all the equipment, surface treatments, and paint supplies you need to do an excellent and long-lasting job. Please download a free copy of our Ultimate Floor Paint Guide to find out more.