Home Improvement

Do you have any access to the inside of the wall, so you can view that section of wall from the back?

Repair will depend on several factors:

Was the correct type of wallboard used when building the wall? If not, and if it's been cracked for a while, a significant amount of water could have gotten through the crack. If significant amounts of water have gotten through, you may need to replace the whole section of wall.

Is there any water damage to the wallboard? Usually, if the correct type of wallboard was used, there won't be any water damage. But I've seen plenty of installers use the wrong kind of board. If the wrong board was used, you may want to replace the whole section of wall, even if there isn't visible water damage. Because if the crack gets worse, it'll be a more expensive repair later.

Does the shower-facing side of wall show any signs of crumbling? If so, it may be patchable, but you'll need to remove the crumbling portions first. Also, if it's actively crumbling, it could be bigger signs of structural issues, and you may want to get it inspected before doing any repair work.

Is the wall stable? Is the cracked area firm? Is there no sign of water damage? There are a few different types of silicone caulk or tile filler you can use to patch the crack. As long as it's patched properly, it shouldn't let water through, and it shouldn't continue to deteriorate.

There could be other considerations, but these are some of the common ones.

If anything seems off, get a professional to look at it. It'll cost more now, but it'll save you time and money later.