What is the largest tank you've seen on a second floor?

[MnFish1]

Remember that IRC is minimums and for entire rooms. No floor is just 40 psf - if it was, you would fall through it if you put both of your feet together since no adult weighs 40 pounds and both of your feet together would likely fit in a square foot.

Leg of a couch with a few adults on it can be many hundreds of PSI as can a heel from a shoe, etc.

You can find 4 floor joists with a 4 foot tank (one on each end and two in the middle), but easily three... and the OSB subfloor is strong too if you are even a few inches from a floor joist.

Heck, some china cabinets up against a wall with the furniture, a bunch of plates and dishes, your gravy boats and platters from your Granny, silver from your Auntie, etc. can weigh well over 1500-2000 lbs all filled up... then you have people walking right in front of it. I have a 625 pound Viking range in the middle of my kitchen with 2" granite countertop island about 4x14 feet, the cabinetry, pots, pans, wind fridge full of wine, etc... this is in the middle of the room and has to weigh 3000 pounds, right?

It would depend on how much wine you drink

 

[reefer_87]

Remember that IRC is minimums and for entire rooms. No floor is just 40 psf - if it was, you would fall through it if you put both of your feet together since no adult weighs 40 pounds and both of your feet together would likely fit in a square foot.

Leg of a couch with a few adults on it can be many hundreds of PSI as can a heel from a shoe, etc.

You can find 4 floor joists with a 4 foot tank (one on each end and two in the middle), but easily three... and the OSB subfloor is strong too if you are even a few inches from a floor joist.

Heck, some china cabinets up against a wall with the furniture, a bunch of plates and dishes, your gravy boats and platters from your Granny, silver from your Auntie, etc. can weigh well over 1500-2000 lbs all filled up... then you have people walking right in front of it. I have a 625 pound Viking range in the middle of my kitchen with 2" granite countertop island about 4x14 feet, the cabinetry, pots, pans, wind fridge full of wine, etc... this is in the middle of the room and has to weigh 3000 pounds, right?

True. But bedrooms are at 30 psf and I was not sure where he wanted to put the tank. Also having a little bit extra leeway 2x-3x is better because these subfloors can sag if not supported properly and if the wood takes moisture even to a small extent.