Henry has noticed a crack running along the inside of the metal control joint on his stucco and wants to know the best way to repair it. He’s curious if it’s a serious issue and what steps he should take to address it.
Question from Henry:
I have a crack all along the inside of the metal expansion joint. How do I repair?

Answer: Hey there, Henry! The crack you’re seeing along the inside of the metal expansion joint is a common occurrence and is usually not a serious issue. To repair it, you’ll want to use a quality exterior caulking to seal the cracked areas. Here’s what you can do:
- Clean the Area: Make sure the joint is free of dust, dirt, and loose material. You can use a small brush and compressed air to clean it thoroughly.
- Apply Caulking: Use a flexible, paintable caulking rated for exterior use (avoid silicone, as it’s not paintable). Apply the caulking into the crack, making sure to fill it completely.
- Smooth the Surface: Use a tool or your finger to smooth the caulk, ensuring it blends well with the surrounding material. A q-tip will work good for this and should fit inside the groove nicely. Try to fill the crack and not the entire groove, if you can help it.
- Paint Over the Joint: Once the caulking has fully cured (check the label for drying times), apply a coat of paint to match the surrounding stucco. This will help blend the repair seamlessly and protect the area from further weathering.
This repair is straightforward and effective for minor cracks like this. The control joint is designed to allow for a small amount of movement, so it’s normal for small cracks to appear over time. Let me know if you have any further questions!