One of the most common concerns people have after refinishing a bathtub is noticing drips, runs, or streaks in the finish once it starts to cure. The good news? In most cases, this is not a failure of the coating and it does not mean you need to start over. These types of imperfections are usually cosmetic and can be repaired with a simple sanding process before applying another coat.
Here’s what causes them and how to fix them.
Why Drips, Runs, and Streaks Happen
1. Applying Too Much Material
Applying a heavier layer than needed can cause excess material to slowly move downward on vertical surfaces as it cures. This can create visible runs or sagging.
2. Room Temperature and Humidity
Temperature and humidity affect how quickly the coating begins to set. If the room is too cold, the material may stay fluid longer than expected, allowing it to shift slightly before curing.
3. Overworking the Material
When the coating is rolled or brushed repeatedly after it has already begun leveling, it can create streaks or uneven texture.
4. Surface Contamination
Soap scum, residue from cleaning products, or oils on the surface can prevent the coating from leveling evenly, sometimes creating streak-like patterns.
The Simple Fix: Sanding the Surface Smooth
Fortunately, fixing these imperfections is usually very straightforward.
Once the coating has fully dried, the repair process is simply:
-
Sand the affected areas smooth.
Use 220-320 grit sandpaper to level out any drips, runs, or textured areas. -
Focus on the high spots.
The goal is not to remove the entire coating, but to knock down the raised areas so the surface feels completely smooth to the touch. -
Clean off sanding dust.
After sanding, remove dust and debris using a vacuum or isopropyl alcohol. -
Apply a new coat.
Once the surface is smooth and clean, a new coat can be applied directly over the existing finish.
In most cases, this second coat will level out beautifully and create the smooth finish you were originally aiming for.
Do You Need to Remove the Entire Finish?
No. This is a common misconception.
Drips or streaks do not require stripping the tub back to the original surface. As long as the existing coating is adhered properly, sanding the surface smooth is all that’s necessary before applying another coat.
A Tip for Future Applications
During the curing process, it can help to check the tub periodically, about every 20 minutes during the first part of the drying period. If you notice a developing run or drip early, it can often be gently smoothed out before the coating sets.
The Bottom Line
Drips, runs, and streaks can look frustrating at first, but they are actually one of the easiest refinishing issues to fix. In most cases, the repair process is simply: Sand the surface smooth and apply another coat.
With proper sanding and preparation, the new layer will level out and leave you with a clean, uniform finish.