One day as you were cleaning, you noticed some paint flakes on the floor. You cleaned them up and went on your merry way — until you saw more the next day. You finally looked closely at your walls and realized that your concrete paint was cracking and flaking. What should you do?
1. Repaint the Problem Spots
If the paint is cracked and flaking only in some places, check if the damage extends down to the bare substrate. If it doesn't, just repair the problem areas.
Scrape the cracked paint using a paint scraper or a steel wire brush. After removing the cracking or flaking paint, sand the rough edges with sandpaper or a sanding block. If applying water-based paint, use fine-grit sandpaper. If oil-based, use medium-grit sandpaper.
After sanding, use a damp, clean cloth to wipe away dust from the surface, then wait for it to dry.
Next, inspect the surface. You must prime any exposed substrate. Use a primer suitable for use with concrete and the paint you will use in the next step.
Once the primer has dried — this should take at least three hours, but it can be longer depending on the primer you used and the ambient temperature and humidity — paint over the properly prepped problem spots.
2. Repaint the Wall
What if the paint is cracked and flaked all over? Or how about if the paint is cracked and flaking only in specific sections, but you can see bare concrete underneath?
In either case, a do-over is the best solution.
The steps are similar to the remedy discussed above, except this time, you'll have to perform them for the entire wall instead of choosing only the problem spots. Moreover, if you can see bare substrate under the cracked or flaking paint, you must resolve the underlying cause.
Specifically, if you see bare substrate under the cracking or flaking (also peeling or blistering) paint, you may have a moisture problem, and this may be preventing the paint from adhering to the surface.
There can be too much humidity inside your home. This can be due to a lack of ventilation or your heavy-handed use of a humidifier. It can also be a waterproofing issue, with condensation from outside seeping through and repelling your interior wall paint. There can also be cracks allowing water incursion, and dampness can also be migrating from inside the house.
Resolving a Moisture Problem
To resolve moisture problems, you can do the following:
● Repair Cracks
Inspect your exterior walls and see if there are cracks that need mending. If there are, repair them.
● Waterproof
If there's water incursion through the walls, you should waterproof your exterior walls.
● Seal
If water is leaking in, use caulking around your doors and windows to plug up water entry points.
●Ventilate
If there's too much humidity inside the house, you should open your windows to encourage air circulation. If this is not possible, install one or more exhaust fans and use wall vents.
Repairing the Paint
Remember to repair the paint only after you have resolved the cause of your paint adhesion problems. Once that's no longer an issue, you can proceed.
Remove the old paint using a paint scraper or a steel wire brush. Since you're baring the substrate, you don't need to be too delicate here. You may even use a heat gun or a sandblaster.
After scraping off the old paint, check the walls for any cracks and holes, and repair them. There are readily available concrete repair patches you can use for this purpose. Once the patch has set, sand the repaired area to remove any rough edges.
Using a damp cloth, clean the surface, dry it, then prime it.
Once the primer is dry, apply the first coat of paint. Once the undercoat is dry, recoat. Depending on the finish you want and the paint you're using, you may have to apply a third coat.
Note: Since you're redoing everything from scratch, why not use decorative interior paint finishes for walls? You can plaster your concrete wall before applying paint. You can even use decorative plaster.
You can use interior decorative paints, too, like Aberdyn.
You can even turn your concrete wall into a fully functioning chalkboard!
Prevent Wall Paint from Cracking and Flaking
Next time you're painting your wall, you can prevent cracking, flaking, and other issues by following these tips:
- Prevent moisture problems. Waterproof, repair wall cracks and holes, check water pipes and plumbing to repair leaks, caulk around doors and windows, and install exhaust fans and wall vents.
- Apply paint on a warm and dry day. However, don't apply paint on a hot surface.
- Make sure the substrate is dry, properly cured, and free of dust, loose particles, and efflorescence before painting it.
- Make sure the primer is completely dry before painting over it.
- Make sure the paint is thoroughly dry before recoating.
- Do not paint over wallpaper.
- Do not apply paint over cracked, flaking, peeling, blistering, bubbling, or otherwise damaged paint.
- Pre-cast or extremely smooth concrete surfaces may have to be slightly abraded for the paint to adhere to the surface. Check your paint's application instructions to see if it's required in your case, and sand your surface using the appropriate grit.
- Do not stir paint too aggressively because that can cause bubbles to form. These can become blisters on the painted surface.
- Slow down your paint strokes if you notice bubbles forming during application.
- Be consistent with your choice of formula. Thus, as much as possible, use latex with latex and oil-based with oil-based. Use this rule of thumb when choosing your primer and the top coat to apply over an undercoat.
Cracked and Flaking Paint: Spot Paint or Repaint
Cracking and flaking paint is unsightly, but you can repair it. If it's a matter of a cracked and flaking top coat, you can fix just the damaged portions. However, if you can see the substrate beneath the cracked or flaking paint, you must resolve the underlying cause and repaint the wall entirely.
Equipaint is the authorized supplier of COLORTEK premium paints in Dubai, United Arab Emirates and Doha, Qatar. Repair and repaint your wall using our premium paint solutions. Contact us.