Commercial Painting comes with its inherent challenges. And if not applied correctly, those challenges can present themselves in unflattering ways.
Here’s how paint becomes victim to cracking and flaking:
When studying the problems, you’ll notice that the cracking occurs through the entire film of paint, all the way to the substrate. This is a common problem when underlying coats of paint are applied to existing coats that have not been adequately prepped.
The underlying coats lose their elasticity. Which means that they can’t bend and flex with the substrate when it expands and contracts during varying temperature changes. So as the substrate swells and compresses, the aged coating begins to delaminate and shingle.
And as this expansion and contraction occur, that causes more stress onto the original coating, forcing the cracks to expand, and the flakes to grow deeper, until they stretch into the substrate.
As always, a root cause of the cracking paint problem can be addressed from the beginning with sound preparation. If you’re considering new paint over an existing application, you’ll want to adequately remove the existing application until you have a sound coating. This doesn’t mean that you’ll need to remove all of the coating.
But what it does mean is that you’ll need to consider varying preparation methods to ensure that you have a sound substrate.
Here are some popular preparation methods to avoid the uncoveted cracking:
- Sanding – this is the easiest method because all it involves is sandpaper and some elbow grease. The aggressive grit on the sandpaper will remove any of the aged paint that has already started to delaminate. And once it’s removed, you can rest easy knowing that you’ve taken care a large portion of the prep. Let it be known, however, that although sanding is a great prep method, it does have its limitations. Which lead us to the next prep method.
- Pressure Washing – Sometimes sanding doesn’t offer enough force to completely remove the loose coatings. So pressure washing is a great way to get rid of the loose coating that has already begun to separate from the substrate. This may not be practical if you’re only painting a small area. So just because pressure washing is a better solution, don’t rely on it as your only prep consideration.
Oil based paints will typically lose their elasticity before latex based paints. So keep this in mind when considering you new coating for your painting project.