Tank safe on this second storey wall?

[Sinister-Kisses]

I'll admit that I'm likely extremely over paranoid about the weight of fish tanks on second storey floors, but I really know nothing about the weight capabilities of house flooring and really do not want to f*#& up my house over a damn fish tank lol. As such, of all my tanks only the 40 long is upstairs. However, I need to set up a 33gal and the "best" spot for it is in my home office which is the second storey...I know it's ONLY a 33, and against any other wall up here I wouldn't even think twice. But the office is located directly above my front entry room, and the office wall I'd like to put the tank against is the wall that runs against the stairwell. As such, the wall ends and becomes just an open floating ceiling/floor above, as you can see. After a quick measurement to compare where I want the tank on the inside of the office to this view on the outside, the red box I've drawn is approximately where the tank will sit.

Tank is your standard 3ft long 33 gallon, has a 2x4 home made stand that a contractor friend made up for me, and won't have a ton of heavy decor (not like hundreds of pounds of rock for mbuna or something), just your standard base level of river rock substrate and some driftwood, etc. Again, literally any other wall upstairs and I wouldn't even question it. But this half wall that doesn't actually run down to the floor has me a bit concerned. House is an older home, built in 1974. Should I find a plan B?

 

[Stephen St.Clair]

The total weight would likely be approximately 300 lbs. That's comparable to a hefty human or a China cabinet.
The joist should be able to support the weight if built to code.

 

[Sinister-Kisses]

Well they likely weren't expecting a china cabinet in a spare bedroom, but who knows lol. I should mention - I checked, and the tank against that wall would be sitting parallel to the joists, NOT across them like would be ideal, if that makes any difference.

 

[Trouser Cough]

The hillbilly test works well and I'd recommend it for your peace of mind.

Outline the area on the floor where you want the tank and get yourself and a buddy or two that in total tip in around 300# and stand in that space. Shift your weight around a little bit. Not like jumping up and down but just shifting your weight from left foot to right and back a few times. Do you hear some uh, sinister noises? If so, those sounds are telling you there could be a catastrophic failure in your future. No sound at all? No creaking, no popping, no nothing? That's usually a very good sign.

The moving around a little bit helps a lot. Dynamic loading is a lot different than static loading. The tank would be a static load and much less likely to cause failure compared to a dynamic load of similar weight.

That said though... the weight of your tank won't be midspan. The pony wall directly underneath is reinforcing that span in a huge way. Personally, I'd wager that you won't notice any sound of any kind when you get a couple buddies together to weight that spot. I'd bet a nickel you could get a couple more buddies in that same footprint and still not hear much.

 

[esoxlucius]

I checked, and the tank against that wall would be sitting parallel to the joists, NOT across them like would be ideal, if that makes any difference.

Yes, those joists will run the way you say. The joists will more than likely be 2x8 or 2x10 or thereabouts and the ends of them will be in that outside wall so of course the wall is load bearing.

Imo you could put that sized tank anywhere in your office you wanted and those multiple thick joists will hardly notice the extra weight. It wouldn't concern me much at all.

Of course running parallel to the joists isn't everybody's cup of tea. But you could throw a correctly sized sheet of 1" ply on the floor to spread the weight and then sit your cabinet on that.

Just don't change your mind and opt for a 300g instead, lol.

 

[RD.]

The following was written by Kevin Bauman, a structural engineer and fish keeper.

Wood Framed Floors and Aquarium Weights | Cichlid Fish Forum (cichlid-forum.com)

HTH

 

[CrazyPhishMan]

i really wouldnt be concerned about such a small tank, no different then someone sleeping in a bed, in terms of weight and perhaps more of a static weight then that.

 

[Sinister-Kisses]

Yeah, 95% of me was like, it's such a stupidly small tank it can't possibly be an issue literally ANYWHERE in my house. But there's that little voice that second guesses...lol.

Thanks. I actually was able to make room for it in my actual 'fish room' room after all, where I would rather it was for simplicities' sake, so it'll be set up there instead. But good to know I'm just being paranoid if I change things up in the future.