If you’ve ever looked closely at the exterior of a warehouse, you will often see hairline cracks in the concrete walls. Commercial Painting Contractors have to deal with this often. These cracks need to be addressed because they are a potential point of water ingress, and if not dealt with, the crack can widen and interior damage to the wall can occur. There are many reasons why these cracks begin, and in this article we will address how to fix them.
A hairline crack, is a crack that is narrower than the width of a credit card. Larger cracks need to be dealt with in their own way and are generally fewer in number.
Repairing The Hairline Cracks
- Cleaning
First off you want to clean the surface around the crack, so that the paint that will inevitably be applied over the crack will adhere. If there is any dirt, mildew, grease, the paint will have a tough time sticking to the wall.
- Scraping
Remove any loose paint or concrete from the surface of the crack. This can be done with a paint scraper, and a wire brush. The goal is to get down to a sound substrate.
- Dusting
Dust away any loose material generated from the scraping.
- Patching
Apply a concrete patch over the hairline crack. A good example of this is Sherwin Williams’ Concrete & Masonry Patch. You want to select one that is flexible so that it will move with the substrate.
- Primer
Apply a coat of concrete primer overtop of to seal it in. If there is efflorescence on the wall that leached out of the cracks, a concrete primer will neutralise it so that it does not affect the paint.
- Painting
Once cured, apply an elastomeric coating overtop of the paint. Elastomeric paint is like applying a rubber band to the building. These products are highly elastic (as the name suggests) and, unlike a conventional paint, will bridge the cracks.
This should go without saying but make sure to wear proper protective equipment. If you the cracks are high, a ladder will be needed. If you are painting the entire building, renting a boom lift is recommended.
If you are dealing with hairline cracks and would like to hire commercial painting contractors to handle the issue for you, we would love to help you.