Supporting a larger tank / Jack from the basement

xmike24

Dog Trainer
So, wanted to see what everyones experiences were with supporting a larger tank from the basement. I have been to multiple homes that have steel jacks to add support for a larger tank, however in the past week I've seen a lot of warnings about it from regular DIY websites.

Anyone know of a good engineer that would be able to double check the foundation and give advice on how to properly support the first floor from the basement.

Info on what I'm wanting/planning on doing.

1. I have a room in my house that is a decent size/layout for a theater.
2. As of right now I've debated putting a new (larger) tank either in the same room, or by the staircase.
3. I would RATHER have the new tank in the new theater room as ever since I moved the tv into this room, the tank hasn't really been looked at much by anyone else other then me.
4. My concern: I want 90g+ tank, possibly 120 as it's the same dimension of a 90, however has 6in extra in depth for rock work,
5. Either way, then 90g alone is 720lbs with water alone. So I'm estimating about 1000lbs for the tank.
6. If I do put it in the same room, there are often times were a decent amount of people are in my house watching a movie. Easily 10 people at a time. Lets round down and say most people are 150lbs... that's literally another 1500lbs added on top of the fish tank (ALL in the same room).


The warnings I have seen for the steel jacks:
1. You should only use them for temporary support
2. If there's ever a fire, the steel will collapse
3. To much weight and/or bad equipment and it will as well collapse: http://www.diychatroom.com/f19/close-call-6603/


Advice?!
 
I think your over thinking this a bit. Realistically your load of people will not be in the tank nor is it likely they will all be close enough proximity to one another and the tank to cause collapse. For peace of mind if you feel necessary double up the 2x12's under the tank and you can put jacks in the corners. The only problem with the jacks ins achoring them to the concrete floor. In new construction they are set into the floor, thus making them permanent. You can anchor them using a wedge lock anchor made for concrete then grout them in at the base. All materials available at home depo. As for the fire issue if your basement has a fire large enough and hot enough to melt or structurally weaken the jacks then my friend you will have far bigger problems to worry about and the tank will likely be boiled. Hope you like sea food! LOL
 
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Well there are lots of things to consider here Mike. First, will the length be parallel with or perpendicular to the joists. A 120 is big, no doubt, but if it's perpendicular, a lot of problems go away. Also what size joists? 2x8, 10, or 12? Will the tank be near the foundation wall, or in the middle of the house? Is their other heavy stuff in the room (tile flooring specifically)? And what and how thick is the makeup of your basement floor?

Even if it's a 120, if it's perpendicular to the joists, 2x12's and near the foundation wall, it's probably just fine. It would be nice if you put some cross-hatching in-between the joists for torsional strength, but that construction can handle the weight. When you start getting to shorter joists, parallel tanks, or near the middle of the room, then things get trickier.

Do remember, that if you do support with steel jack posts (cause our tank is parallel or you'll sleep better at night), you're not supporting the weight of the entire tank, just the extra that the joists can't handle. So for something like a 120, it's not worth pouring footings for the jackpots in the basement since it's not THAT much weight. The concrete floor can probably handle the load. When you start getting to really big tanks, then you need to think about pouring footings.

As for the folks saying they should only be for temporary support, my 100 year old house is held up by them... And if there's a fire, you have more to worry about than collapsing steel jackposts... And even as heavy as it is, it's nowhere near the weight of risking collapse of them.
 
These guys have given good advice so far, but I wanted to reiterate from my house building experience:

*Steel posts are fine and are used in new construction all the time. They're typically rated for 10,000 lbs depending on length. They are not a fire concern or any other kind of concern. I would tie them to the concrete floor so they don't get bumped out of place.

This is all very dependent on the specifics of your room. Could you post a picture? I agree: for a 120, you don't need to pour a footer for the post(s) if you have a slab that's 4" thick or more.
 
People do stupid stuff all the time. I had crazy heavy gun safes and king sized water beds. I wouldn't sweat it. The foot print for safes is tiny in comparison. Especially if the tank is closer to the walls.
 
Unless your house is run down pos Then a 120 gal tank is not even going to come close to overloading the floor joints. I build additions and do remodeling so you can believe me or not.
 
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