Calling all sturctural Engineers.

[xxxbadfishxxx]

Ok, i am upgrading to a 120 Gallon tank (48x24x24). I overestimate it to be around 1400lbs or so (tank weight, water, rock, stand. Sump will be located in basement). I have engineered floor joists that are 24" on center. My tank will come close to resting on three joists, i want to build a fish closet underneath it, but the third joist is a little further then i originally thought. The tank will be on a load bearing wall (side of house). My questions are

1 - Do i even have to support these joists?
2 - Can i just support two of the joists?
3 - Anything i am missing?

some pictures.

These are what they look like
http://i12.photobucket.com/albums/a241/typesjeff/DSC_0158.jpg

http://i12.photobucket.com/albums/a241/typesjeff/DSC_0160.jpg

http://i12.photobucket.com/albums/a241/typesjeff/DSC_0161.jpg

[Nuuze]

I asked the same here:
http://reefcentral.com/forums/showthread.php?threadid=1335215&perpage=25&pagenumber=1

I think several folks here said 150G or less should be okay. Maybe more will see this thread and chime in.

[xxxbadfishxxx]

from several people i talked to they say the engineered joists are extremely strong, and the fact that i will be close to three of them, and only two feet OFF a Load bearing wall i should be okay. I want to here from the experts though, I will Support the two the tank rest on, but the third joist is a little further then i thought. here are some pics on where the room will go.

http://i12.photobucket.com/albums/a241/typesjeff/DSC_3326.jpg

http://i12.photobucket.com/albums/a241/typesjeff/DSC_3332.jpg

http://i12.photobucket.com/albums/a241/typesjeff/DSC_3333.jpg

[Bruno3047]

Deleted.

I misunderstood what you were trying to accomplish.

[wmilas]

Those look like laminate joists. Are the runners (the part on the top and bottom, not the center chipboard filler) laminate? Ie do they look like thin pieces of wood glued together?

If they are, you should have no problem being right on a load bearing wall assuming your tank intersects at least 2 of the joists. Out of curiosity how long is the span to the next bearing wall and what kind of load is on the floor above? Is it tile? Is it carpet? If its a 12' or 14' foot span don't worry. If its a 22' span with tile, maybe worry a little :)

The only thing you have to worry about if its a short span is getting those things wet. The glue that holds those things together can weaken with prolonged moisture contact. Ie try not to have a tank accident :)

If you are really worried a framed 2x4 wall for the fishroom would completely ease your worries :)

[crvz]

Not a structural engineer, but I will say that I'd do it without a lot of worry. Good luck!

[fishgeeksrus]

Not a structural engineer, but I do work construction.

If your plan is to build a closet underneath, bring it all the way up to the ceiling and use it as additional support for the tank. The fact that you're putting it against a load bearing wall, the wall will be picking up the vast majority of the weight. I don't see any problems in putting in your tank.

[N-A-S-O]

I found this info helpful when I had the same question.

http://badmanstropicalfish.com/articles/article28.html

[o.c.d.]

Thank you N-A-S-O, very informative .

[xxxbadfishxxx]

well i dont know whether or not i should feel good after reading that because mine are 24" on centered and are the Engineered joists. I dont plan on getting them wet. Floor under tank is Hardwood floors, and the spans to adjacent load bearin walls isnt too far, i can get measurements tonight. I did start building the room, i hope it is good, i basically put two 2x4 posts nailed together under the two joists the tank will be resting on.

would like to get more peoples opinions, i have some pictures in my build thread, i will take more tonight.

http://www.reefcentral.com/forums/showthread.php?s=&threadid=1324377&perpage=&pagenumber=2

[Mike31154]

120 gal sounds like close to what the average bathtub will hold. I'm sure you have one of those somewhere in your house, also close to a load bearing wall. Check out the configuration of the studs under that and it should give you a good idea if you're on the right track.

[wmilas]

if you have 2x4's under the joists you'll be more than fine. Hell, as it is unless you have a ton of tile on the floor above, and greater than 24 foot spans you'll be fine most likely. Those joists are much stronger than conventional 2x6/10/12's .

[xxxbadfishxxx]

thanks for your comments, any reason i should cross brace them?

anyway, here are some pics. I have two 2x4s under the two Main Floor Joists. Still more work to be done.

http://i12.photobucket.com/albums/a241/typesjeff/DSC_3332.jpg

http://i12.photobucket.com/albums/a241/typesjeff/DSC_3335.jpg

http://i12.photobucket.com/albums/a241/typesjeff/DSC_3337.jpg

http://i12.photobucket.com/albums/a241/typesjeff/DSC_3338.jpg

[o.c.d.]

I I was you I would not be shy about using extra wood in that closet you could even add a back wall, ether frame over and move plug or demo the drywall and add wood . One thing I don't like is the very top horizontal stud you cut it for the difference of the drywall thickness.

[Bruno3047]

Looks fine to me. If you want to add a little extra, you might want to put a structural header over the doorway.

Maybe a 2X6 on jack studs.

[niles1967]

Cross bracing will stiffen the joists but it is not necessary. Would you be concerned if 7 grown men were standing there? No. Same thing. A dining room breakfront could easily weigh twice that but you wouldn't think twice about putting one there. (buy the way, I have been in residential construction for 25 years.)

[o.c.d.]

Ya "not necessary" But if your like me and don't want to ever half to worry about then beef it up while the walls open, sucks to do it later. And what if 7 grown me are standing there then you have 7 men and your tank Hmmm. Sorry too many men please only three to see the tank at a time.

[xxxbadfishxxx]

Actually before the build i didnt think about the back wall, its actually supporting the floor as well. the wall is build roughly 8" from the concrete foundation, this puts the wall runs parallel underneath the tank by i would estimate 1 foot. The side of the closet i built also runs directly under the center joist that is underneath the tank. I hope its safe to sat that i supported the tank more then enough.

[o.c.d.]

I over build, personally I'd have a jack under it wood changes shape with moisture and heating. And a jack is easy to instal and not that expensive . Peace of mine is what you are buying. Not to mention falling through the floor is not going to happen but a sagging floor stresses the sides of the tank eventually blowing. you want a level tank even over time, wood can't promise that.