Can my floor support it

TheWhiteFord

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I need some help from the builders and structural engineers on here. I stumbled across a ridiculous deal on my dream 300 gallon deep dimensions tank (6ft L x 3ft W x 27” T). I was initially gonna put a 150 gallon tank in this spot (hence the plumbing). I am concerned if my floor can support it. Can anyone help me?

I laid out a tape measure one floor and then hung it from the ceiling to show how far it comes out from the load bearing beam. It would be sitting on 4 of the joists.

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How are the joists supported on the other side behind you? How long is the span? All those things play a major factor.

Build another support wall underneath those joists to take some of the load and it would likely be more than fine. They look sturdy as is. But it depends on the factors above.
 
I agree completely that the floor can handle the weight without further modifications. Save your money for frags and start a build thread so we can follow the results, either way.

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Agree with the above. Spend the money ahead of time to hire a structural engineer.

Having said that, if the tank will sit perpendicular to the joists and the wall is load bearing, you’ve got a good shot. That’s how my 240 is configured and it’s done fine for 9 years.
 
Happy to do a load calculation for you.
What’s the size are the floor joists?
How long do they span between supports?
You say the tank is on 4 joists, so perpendicular to joists?
 
I installed a 280 on the second floor of my last home.

EDIT: By 'Second Floor', I meant the main floor of my home, with a basement underneath. Sorry for confusion!

I had a contractor come in and add vertical supports underneath and expected we would be good to go.

Within a week I noticed the floor dropped enough that the water wasn’t hitting the overflow right.

The deflection on the floor was unreal. I lost many nights of sleep.

I then had an engineer come out and said it was fine temporarily but we needed some LVL (?) beams. He cost me $600 for the plans.

I was in talks to get a contractor to install the beams when we decided to move homes for unrelated reasons.

This is long way of saying: Get an engineer if it isn’t going on a slab.
 
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I installed a 280 on the second floor of my last home.

I had a contractor come in and add vertical supports underneath and expected we would be good to go.

Within a week I noticed the floor dropped enough that the water wasn’t hitting the overflow right.

The deflection on the floor was unreal. I lost many nights of sleep.

I then had an engineer come out and said it was fine temporarily but we needed some LVL (?) beams. He cost me $600 for the plans.

I was in talks to get a contractor to install the beams when we decided to move homes for unrelated reasons.

This is long way of saying: Get an engineer if it isn’t going on a slab.
If the second floor was originally designed for bedrooms, depending on when it was built, it could be as low as 20 psf (pounds per square foot). Someone adding a bathroom without permits after that fact doesn’t count. Whereas the first floor can only be as low as 30. Nowadays 40 on first floor, 30 on second.
The other thing to consider when talking about a tank filled with water that calculations and codes don’t address is bounce. Will the floor bounce when you walk past it with the added weight.
OP’s situation is different, with the basement below. Adding a support looks pretty straight forward in the pics.
 
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Not on topic, but those long horizontal runs on your drain might cause issues with flow.
The run is only about 6’. You think that will be an issue? Its dual 1-1/2 inch drains so I thought I would be fine but please correct me if I am wrong Now is the time to fix it lol
 
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Happy to do a load calculation for you.
What’s the size are the floor joists?
How long do they span between supports?
You say the tank is on 4 joists, so perpendicular to joists?
I will get you the measurements when i get home
 
I am getting an engineer to come look at it as everyone has recommended. I am building an extra support exactly like the one attached to this post and bolting it into the slab
 

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Unfortunately, yes I do. But even making a pitch of a couple inches will help out a lot. My old setup had only 2 feet of a horizontal run, and it was always a problem to dial in the full siphon.
Okay I will run it at angle into a 45° instead of straight over to a 90° Thanks for the heads up
 
If the second floor was originally designed for bedrooms, depending on when it was built, it could be as low as 20 psf (pounds per square foot). Someone adding a bathroom without permits after that fact doesn’t count. Whereas the first floor can only be as low as 30. Nowadays 40 on first floor, 30 on second.
The other thing to consider when talking about a tank filled with water that calculations and codes don’t address is bounce. Will the floor bounce when you walk past it with the added weight.
OP’s situation is different, with the basement below. Adding a support looks pretty straight forward in the pics.
To clarify, my situation was indeed on the main floor with a basement below. I just refer to it as 2nd floor. Sorry for the confusion.
 

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