New tank weight-A problem?

[sslarison]

OK bear with me. This is is a drawing(extremely rough) of my front room. When I looked under the house I didnt measure but it looks like the joists are 16" apart from one another and there are large beams running perpindicular to them about every 25" or so. I didnt put the beams in the picture because I dont remember exaclty where they were. This gives you a gereal idea anyway. The retangle that has a T on it is the tank. The dark black lines are doorways.

 

[Anonymous]

Hmm, you have joists 16 inches on center and then larger beams perp. to those 25 inches on center? I'm no engineer but something doesn't sound right.

Either way, if that were my house and that was a basement underneath, I would use two floor jacks on the joist under the tank as it is placed there.

 

[sslarison]

Ok, obviously assume that I dont know what I'm talking about here. Forget my drawing. :lol:

I am not getting the 90g after all but I'm going to get a 75g. But anyways this is what it looks like under the house and imagine that I'm putting the tank on the right side of this picture paralell to the joists.

The wall the tank is going to be up agianst is the wall that divides the house from the garage. Is this considered an exterior wall? If so thats good right?

Sorry guys, I just dont know anything about this structural stuff.

 

[Len]

Usually, that wall will be load bearing so that is a good thing. I don't think you'll have a problem with the 75g, but if you have the time and energy, two supporting pillars between the subfloor and supporting joists would give you absolute peace of mind.

 

[Anonymous]

I have my 110ga in my mobile home. I think you will be fine.

 

[ChrisRD]

How long are the joists (the longer ones in your pic) and what size are they (ie. 2 X 10, 2 X 12, etc.)?

 

[sslarison]

How long are the joists (the longer ones in your pic) and what size are they (ie. 2 X 10, 2 X 12, etc.)?

Its hard to say. I dont really remember how long they are. They look like to 2x10 though.

 

[trido]

I have my 110ga in my mobile home. I think you will be fine.

:lol: :lol: Now you, my friend, truely are tempting fate. Ive seen how those are built and I'm usually paraniod and stressed anyway. :lol: :lol:


From your description you said that you have floor joists 16"O.C. and girders 25"O.C. perpendicular to the joists. That doesnt sound right. Supporting residential girders (on the west coast anyway) are typically either 4 or 8 feet on center. The joists are most likely 2x10 or 2x12s. If it is against the garage wall it most likely does have a concrete footing and stem wall under the framing like all of the exterior walls.

Like Len said, If you can weasel a couple of peir pads and 4x4 posts under the joist in question. It really is better to be safe than sorry if your going to lose sleep over it Its only $15 in material and a thirty foot belly crawl. We all have our point of cant sleep at night over it as you can see.

Personally, If it is only a 75G. I would put it as near the girder underneath the joists as possible and would leave it at that. You will be fine.

 

[sslarison]

Thanks Trido. You guys are awsome. I really appreciate all of your help.

Scott

 

[ChrisRD]

I did some quick calculations to give you a ballpark idea of what you're dealing with going parallel to the joists. Of course I'm basing this on your sketch and making a lot of assumptions, so this is just a rough guide...

If you have 2 X 10 joists and they are spanning more than 7' unsupported you should provide additional support (to the effected joists). If your joists are 2 X 12 you're good to a span of about 10' before you start to need additional support.

HTH

 

[sslarison]

Thanks ChrisRD. I know there is a girder/peir post (see the second diagram I posted) near the area of where the tank is going to go. I remember seeing that when I looked. Do you think if I positioned the tank over that I'd be ok?

Scott

 

[ChrisRD]

Yeah, with direct support under the joist like that you will be fine for sure.