I just replaced a couple of outdoor light fixtures and noticed some gaps in the stucco around the base. The gaps were visible with the old fixture too, but even more so now because the new ones have a slightly smaller base. How can I fix this? I thought about “great stuff” expanding foam, but I’m afraid that would fill the whole wiring box and be a mess if I ever had to change the wiring. Not sure if that’s safe either.

enter image description here enter image description here

  • make them moist before you use spatula and stucco
    – Traveler
    Dec 30, 2022 at 3:58

1 Answer 1


The first step is that you need to either replace the box or (more likely much easier) extend it so that there is no gap between the fixture and the box. Something like this extenion from Lowes:

round extension

The extension screws into the existing box. The light fixture screws into the extension. All wiring is now inside the box and extension, protected from lots of problems.

Once you have done that, you can fill the cracks with foam or with some other filler compound. I would actually put on the extension, fill carefully around it, and then reattach the light fixture, rather than trying to fill with the light fixture in place.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.