Any floor protection under a tank?

[MichaelB]

I'm aligned that's a good/reasonable solution. The big thing though is all any of these solutions will help with is a very small amount of water. Realistically only helping catch the equivalent of a slightly leaking bulkhead until you visually see the drips or a leak sensor triggers.

For example, looking at the pic there, it looks very watertight, but the total volume it's going to capture is length * width * height of the area that's free.

My guess is the area that doesn't have the sump sitting in it (which doesn't count) is something like 5cm * 3cm * 5cm on each side.

Let's round way up and say it's 10cm*10*10 * 4. If you ask Google:

(10cm*10cm*10cm*4) in gallons

Google says 1 gallon. So none of these will help with a 30 gallon spill.

I think they're still worthwhile, but good to keep in mind their efficacy.

The linner went up the side walls about 5 inches all around the sump. There was also about 6 inches behind sump from back wall, maybe 5 inches from front, not counting all the space on both sides.

It would have easily held close to 25-30 gallons of water under the stand. Assuming some water would have also remained inside the sump and it didn’t burst apart and shatter a seam etc.

I'm not that good with math lol to break it down how you did. However there was enough space open it could easily hold 3 up to 4 times what sump could. Keeping in mind sump is only filled roughly half way or so. i was also pointing out a over flow power lost situation not a total tank or sump failure.

Way more than just a single gallon of water.

I take your point though if someone has a sump thats inch from sides of stand probably won't help much for a significant overflow. So I imagine its effectiveness would vary based on the space around the sump and height of the shower liner on each side.