Need structural advice for potential aquarium

[i_declare_bankruptcy]

I'm looking at a 72"x24"x17" acrylic tank right now. I'd like to put it in my office where I could stare it all day However, that would place it as shown in the picture -- away from any load bearing wall, suspended by joists. From my understanding that is a no-no BUT when I got under my condo it appeared pretty well supported. Something I forgot to diagram is that there's a (non load bearing) wall to separate the guest bath from my office which is what the tank will back up against (the bathroom is between that white load bearing wall and the tank in the diagram).

There is a 2"x8" joist (right word?) every foot it appears. The length of the run is approximately 18 feet, and the tank will sit approximately 6 feet from that white load bearing wall.

My understanding is:
- Tank volume is approx 127g
- Unsure of sump size but appears large
- Tank is on a sturdy steel stand
- Tank is made by Advanced Acrylics
- Tank is about 3/4" - 1" thick according to seller
- My guess is it will weight about 1400lbs wet
- Tank will sit across 7 joists, perpendicular
- Therefore load on each joist will be ~200 lbs

It's a condo so I can't willy-nilly add supports unfortunately. And it's built into a hillside so that wouldn't be easy either.

I know that's not the whole story so that's why I'm asking for other people's opinions. Any advice?
Thanks

 

[PbMan26]

It would probably be ok. I'd be worried about a little sag if anything.

How are you sure the bathroom wall isn't load bearing?
What is the flooring the tank will sit on?
Is that a basement or crawlspace?
Poured concrete down there? I'd build a wall underneath those joist just to be sure. Not sure how handy you are.

 

[fishguy242]

following for floor of basement or crawl

 

[i_declare_bankruptcy]

Here's more info:

Was built in late 70's.

Property sits on a hill/terrace; the ground to the right of my head in the picture is sloped.

It is a condo so I cannot easily add reinforcement without HOA approval (and would have to deal with the sloped ground).

The white wall in the picture is load bearing; the bathroom extends to the *right* of that white wall (you can see the water station guest shower drain and toilet drain), which has a non-bearing partition wall to separate it form my office (further to the right; where the aquarium sits).

The white wall sits on concrete I think (to the left of that wall sits the bottom level / basement / bedrooms which are slab on grade).

I think the 2x8's may be technically 2x10's I may have measured wrong, I know wood in now is actually smaller than the listed dimension.

Tank will sit on hardwood floor with a heavy duty steel stand that should do a great job distributing the weight.

 

[fishguy242]

directly under tank is sloped concrete?

 

[i_declare_bankruptcy]

directly under tank is sloped concrete?

Sloped dirt, not concrete (not sure the technical term)

 

[BrandonS]

As much as it sucks if your not sure or confident get the opinion of an engineer.
16 feet is a big span for 8 inch joists. Plus the tank would possibly considered a live load which puts more stress on the supports. Can you put it closer to a wall? Reefdudes on YouTube did a live stream about this stuff and had an engineer friend on.

 

[BrandonS]

Here's more info:

Was built in late 70's.

Property sits on a hill/terrace; the ground to the right of my head in the picture is sloped.

It is a condo so I cannot easily add reinforcement without HOA approval (and would have to deal with the sloped ground).

The white wall in the picture is load bearing; the bathroom extends to the *right* of that white wall (you can see the water station guest shower drain and toilet drain), which has a non-bearing partition wall to separate it form my office (further to the right; where the aquarium sits).

The white wall sits on concrete I think (to the left of that wall sits the bottom level / basement / bedrooms which are slab on grade).

I think the 2x8's may be technically 2x10's I may have measured wrong, I know wood in now is actually smaller than the listed dimension.

Tank will sit on hardwood floor with a heavy duty steel stand that should do a great job distributing the weight.

A 2x10 is 9 1/4.

 

[i_declare_bankruptcy]

As much as it sucks if your not sure or confident get the opinion of an engineer.
16 feet is a big span for 8 inch joists. Plus the tank would possibly considered a live load which puts more stress on the supports. Can you put it closer to a wall? Reefdudes on YouTube did a live stream about this stuff and had an engineer friend on.

Agreed with your assessment. I have a good friend who owns a construction company coming out tomorrow to see, just trying to scrape up lots of opinions. I personally feel uneasy about it but I'm a wimp.

Unfortunately it's on a partition wall right now, so no way to get it closer to a load bearing wall unless I shift it towards the exterior wall labeled in the pic but then it would look silly and likely not be much stronger (that wall would run perpendicular to the tank, so wouldn't add much support)

 

[PbMan26]

Real hardwood? That is good. They should have installed it perpendicular to joist. That would help to spread the load to another joist on each side.

What the HOA don't know can't hurt them

 

[i_declare_bankruptcy]

Let me upload another pic I think I'm not doing a good job explaining. Agreed about the HOA.

 

[i_declare_bankruptcy]

This should explain what I'm trying to say:

 

[fishguy242]

i am glad to hear you have someone to put eyes on, if found need support ,would dig out a little pour either 6" level slab,or two holes w concrete piers ,1 two posts and a sound beam w piers ,or slab w 2x8 wall,good luck,hope to see a tank soon

 

[BrandonS]

i am glad to hear you have someone to put eyes on, if found need support ,would dig out a little pour either 6" level slab,or two holes w concrete piers ,1 two posts and a sound beam w piers ,or slab w 2x8 wall,good luck,hope to see a tank soon

Two piers with concrete footings wood do it for sure. Hard thing for you is the slope. I have a much smaller crawlspace and was able to add 2 piers and a 4x6 beam under each rack of tanks in my old fish room. Made the floor solid with 20 tanks on it.

And now I have two kids instead. Lol

 

[i_declare_bankruptcy]

Yeah the slope and the fact that it's soft dirt. Oh and the ground is about 5-10ft below the joists depending on where you add the support. At that point I'll look at placing the tank elsewhere haha.

 

[fishguy242]

couple sonic tubes,few bags concrete ,couple 6x6,and a beam not too bad idea ,bury tubes 18-24" leave 16" above grade,little work,bet under 100.00

 

[sharpimage]

I do structural work in South Florida. I would be concerned with that much load, that far from a bearing wall. I would enlist an engineer to do some calculations.

The piers under it would work, if the HOA would let you, which they won't so don't ask.

 

[i_declare_bankruptcy]

Engineer friend visited today. Thinks the floor could probably handle it but agrees not to risk it. We will be adding support similar to how was suggested by @fishguy242 (though he thinks 4x4 posts and a 4x8 beam will suffice). I'm pretty nervous about the HOA not approving it -- that would really SUCK but I guess it's a risk I'll have to take.

 

[fishguy242]

you own? don't tell,easy enough to remove flush to dirt if selling 6x6 ,few dollars more,and no worries,bowing,checking,
4x8 cool beam,bam now we got a build,take lots of pic's

 

[i_declare_bankruptcy]

you own? don't tell,easy enough to remove flush to dirt if selling 6x6 ,few dollars more,and no worries,bowing,checking,
4x8 cool beam,bam now we got a build,take lots of pic's

I own, closed on it not even two weeks ago and I'm already going nuts. What's wrong with me LOL. Advice taken!