Alligatoring Paint: What You Need to Know

Alligatoring Paint
Picture of Chris Heerdegen
Chris Heerdegen

Alligatoring paint is a pattern of cracking in the paint film that resembles the scales of an alligator. This usually happens on wood surfaces and is marked by cracks that don’t expose what’s underneath. It’s caused by things like old oil-based paints, bad painting techniques, and the environment. Knowing why this happens and how it affects your paint job is key to fixing and preventing this common issue.

Key Takeaways

  • Alligatoring paint resembles alligator scales and often appears on wood surfaces.
  • Cracked paint from alligatoring can lead to moisture damage and structural issues.
  • Old paint and improper surface preparation are common causes of alligatoring.
  • Use a heat gun to safely remove stubborn layers of old paint.
  • Latex paint is flexible and less likely to crack, making it a good choice for repainting.
  • Maintain paint film elasticity by minimizing exposure to extreme environmental conditions.

What is Alligatoring Paint?

Alligatoring paint looks like scales on an alligator. You’ll often see it on wood surfaces, with cracks that interlock but don’t reach the wood underneath. This rough, uneven texture messes up the smooth finish you want for your painted surfaces.

Signs of Alligatoring Paint

It starts with small cracks, often due to old paint or bad application of oil-based paint over a flexible coat. As temperatures change, causing the paint to expand and contract, these cracks get bigger and can eventually show the layers underneath. If you put a hard coat over a glossy surface or use too much paint, the alligatoring gets worse, making the surface look old and worn out.

Long-Term Effects

Ignoring alligatoring paint can lead to bigger problems. Cracked paint lets moisture in, which can cause peeling, wood rot, or other damage. This not only looks bad but can weaken the structure. Fixing alligatoring paint involves scraping off loose paint, sanding the surface, and using a good primer and top coat to ensure the paint job lasts. Preparing the surface right and using compatible paint products will help avoid future problems, keeping your painted surfaces looking good and working well.

Causes of Alligatoring Paint

Inadequate Surface Preparation

Not prepping the surface properly before painting is a big reason for alligatoring. This means not cleaning and drying the surface well, leaving stuff behind that affects how the paint sticks. Surfaces need to be sanded and primed so the paint adheres properly and stays put.

Incompatible Paint Layers

Putting incompatible paint layers together is another major cause. Using a rigid or oil-based topcoat over a more flexible undercoat can lead to cracking because the top layer can’t move with the paint underneath. Different paint types or brands might not stick well to each other, so make sure all your paint products are compatible.

Environmental Factors

The environment plays a big role in alligatoring paint. Extreme temperature changes make the paint film expand and contract, leading to those alligator-like cracks. High humidity and direct sunlight can speed up paint degradation, making new paint more likely to alligator. Allowing proper drying time and controlling the environment during painting can help reduce these effects.

Negative Effects of Alligatoring Paint

Aesthetic Impact

Alligatoring paint can seriously mess up the look of your surface. Those cracks and scales make the paint job look uneven and unattractive. On the outside of your home, it reduces curb appeal, making your property look old and poorly maintained. Even if the paint is new, alligatoring can ruin the smooth, glossy finish you were aiming for, leaving a surface that’s full of cracks and texture issues.

Cracked Paint and Structural Damage

But it’s not just about looks—those cracks can cause serious structural problems too. When the paint cracks, it allows moisture to get in, which can lead to more damage. This moisture can seep into the layers underneath, causing the paint to peel and speeding up the deterioration of the material beneath. In severe cases, this can lead to rot and other structural issues. That’s why it’s crucial to address alligatoring paint promptly by scraping off the loose paint, sanding the surface smooth, and applying a high-quality primer and top coat to keep moisture out and extend the life of your painted surfaces.

How to Fix Alligatoring Paint

1: Surface Preparation Steps: Remove Old Paint

Start by safely removing loose and flaking paint. Use a putty knife or scraper to gently lift and peel away the cracked paint without damaging the underlying surface. For stubborn layers, a heat gun can soften the paint, making it easier to scrape off. Always follow safety guidelines when using heat tools. If there are multiple or particularly tough layers of paint, chemical paint removers can be effective. Apply the remover according to the manufacturer’s instructions and allow it to penetrate the paint film. Once softened, use a scraper to remove the old paint. This process might need to be repeated for thick or multi-layered coatings.

Thoroughly clean the surface to remove any dust, dirt, and residue. Use soap and water or a mild detergent to scrub the area, ensuring all contaminants are gone. Rinse the surface well and let it dry completely to avoid future moisture-related issues.

2: Repair and Priming

Once the surface is clean and dry, fix any cracks and imperfections with appropriate fillers and putties. Apply the filler smoothly and sand the area to ensure a seamless finish. This step is crucial for creating a uniform surface for the new paint. Select a high-quality primer suitable for the specific surface and conditions. Applying a primer helps to seal the surface, improve paint adhesion, and provide a uniform base for the topcoat. Use proper techniques to apply the primer evenly, ensuring complete coverage. Allow sufficient drying time as recommended by the manufacturer before proceeding to paint.

3: Painting

Choose high-quality, compatible paint products for the job. Opt for paints with good flexibility and durability, like acrylic latex paints, which adapt better to temperature changes and are less likely to crack. Ensure the paint is suitable for the surface and environmental conditions.

Preventive Measures

Regular Maintenance

Regularly inspect painted surfaces to catch early signs of cracking or peeling paint. Addressing small issues promptly can prevent larger, more costly repairs. Inspecting newly painted surfaces periodically helps catch potential problems early. Dirt, grease, and moisture can compromise paint adhesion, leading to cracked paint and other issues. Use mild detergents to clean painted surfaces, ensuring they are thoroughly rinsed and completely dry afterward. This upkeep helps maintain a smooth, glossy finish and prolongs the life of the paint.

Managing Environmental Effects

Minimize exposure to extreme environmental conditions to prevent alligatoring. Protect painted surfaces from direct sunlight, high humidity, and temperature fluctuations whenever possible. For exterior surfaces, consider using protective coverings or shading structures to reduce direct sunlight and weather impact. Inside, maintain a consistent temperature and humidity level to preserve the paint film’s elasticity. Use high-quality, UV-resistant, and weatherproof paints for exterior surfaces to combat the effects of direct sunlight and temperature fluctuations. These paints are formulated to withstand harsh conditions, preventing the natural aging and degradation of the paint film. Applying a high-quality primer before the topcoat ensures better adhesion and durability, further safeguarding the painted surfaces.


Alligatoring paint can be a real headache, but with the right prep and products, you can keep your surfaces looking great. Remember, proper surface prep, choosing the right paint, and regular maintenance are key. Address those cracks early, and you’ll keep your paint job smooth and long-lasting. Happy painting!


What causes alligatoring paint?

Improper surface preparation, old paint, and environmental factors.

Can I paint over alligatoring paint?

No, you need to remove the cracked paint and prepare the surface properly first.

What type of paint helps prevent alligatoring?

Acrylic latex paint is flexible and less likely to crack.

How do I remove stubborn old paint layers?

Use a heat gun or chemical paint removers to soften and scrape off old paint.

How can I prevent alligatoring paint in the future?

Ensure proper surface preparation, use compatible paint layers, and protect from extreme environmental conditions.