Use a Paint Conditioner

Mix a paint conditioner (also called a flow additive or extender) into your paint before application. Conditioners slow drying time, improve leveling, and reduce brush marks, which helps produce a smoother, more flexible finish that is less prone to cracking.

Why It Works

Paint cracks often form when the surface layer dries too quickly, before the underlying paint has cured. Conditioners like Floetrol (for latex) or Penetrol (for oil-based) extend the open time so the paint flows out evenly and dries as a uniform film. This is especially helpful in hot, dry, or windy conditions where rapid drying causes problems.

Tips

• Follow the manufacturer's mixing ratio -- typically 8 ounces of conditioner per gallon of paint
• Stir thoroughly rather than shaking, which introduces air bubbles
• Especially useful when painting large surfaces like ceilings or exterior siding where lap marks and uneven drying are common
• Does not replace proper surface preparation or priming -- it improves application, not adhesion