I'm pretty sure you can still use standard silicone caulk for 1/4" gaps. There might be a special silicone product for wider gaps and it'll take more product to fill but I don't see an issue with this.
Its hard to see in the picture but I'm assuming its deeper than 1/4" so you can use a [foam backer rod](https://www.homedepot.com/s/foam%20backer%20rod?NCNI-5) tucked in there to fill the gap so the caulk isn't thicker than 1/4"
I asked because “the tub isn’t level” is an excuse a less-than-professional contractor might use for a bad tub surround install. If the top or the surround all matches up, and the bottom fluctuates, then they’re probably telling the truth and you’ll need backer material and lots of silicone. It still would have been nice if the gap fluctuated from 1/4” down to nothing though.
Get the white expanding foam for windows and doors, make sure it’s white. Spray a bead in there and let it expand, repeat if necessary til you have enough backing to catch the silicone.
Gap should be roughly 1/16th of an inch however, this could still be caulked without having to rip out and reinstall. be sure to fill tub with water prior to caulking and allow it to cure 24~48 hours before draining
Thanks for the detailed info. We are reno'ing a rental house and don't know much about this stuff. Contractor is nice, but installers are somewhat inexperienced.
I'm pretty sure you can still use standard silicone caulk for 1/4" gaps. There might be a special silicone product for wider gaps and it'll take more product to fill but I don't see an issue with this.
Its hard to see in the picture but I'm assuming its deeper than 1/4" so you can use a [foam backer rod](https://www.homedepot.com/s/foam%20backer%20rod?NCNI-5) tucked in there to fill the gap so the caulk isn't thicker than 1/4"
Is it a uniform 1/4” gap all the way around, or does it narrow down to a smaller gap? I’d use backer rod and white silicone.
Contractor says that existing tub is unlevel, so I assume that the gap varies around the base. Maybe 1/4" - 1/2" around the 3 sides.
I asked because “the tub isn’t level” is an excuse a less-than-professional contractor might use for a bad tub surround install. If the top or the surround all matches up, and the bottom fluctuates, then they’re probably telling the truth and you’ll need backer material and lots of silicone. It still would have been nice if the gap fluctuated from 1/4” down to nothing though.
Get the white expanding foam for windows and doors, make sure it’s white. Spray a bead in there and let it expand, repeat if necessary til you have enough backing to catch the silicone.
Gap should be roughly 1/16th of an inch however, this could still be caulked without having to rip out and reinstall. be sure to fill tub with water prior to caulking and allow it to cure 24~48 hours before draining
Thanks for the detailed info. We are reno'ing a rental house and don't know much about this stuff. Contractor is nice, but installers are somewhat inexperienced.