Worried: big tank above garage..need ideas
 

I have a bonus room over my garage that I want to add a freshwater tank. The biggest concern is the amount of weight it can support. What I have in mind is a tank around 180g (72x24x24) but not sure if that's too hefty?
The tank will be placed along the exterior wall in the bonus room where it lines up below (garage) along the same exterior wall. That supporting wall in the garage is unfinished and I can see 2x6 studs @16" on center. There is also a support beam right in the middle where the tank situated right above.
Here's an amatuer depiction of that.

Attachment 3361

Will this size tank and wall support work together? Am I over looking anything? Please reply if you have similar size tank on your main floor. Thanks.

Most floors should be able to support the weight. I was told a typical tank displaces the weight to about 200 lbs per sq foot. I am over 200 lbs and have never had a fear of falling through my floor.

It depends on how thick your sub floor is as well. I have double 3/4" std ply on mine. Just pull out a floor register and take a look.

hahahahaha...
so funny.
man that would make for a crappy day...lol

+1 :mrgreen:

I think it has alot more to do with the dead weight being stationary for long term. Joists saging and weakening other surrounding structures. I am worried about it buckling the floor and falling thought? Mind you the whole setup will be well over 2500lb siting on 12sq ft. of floor. Does anyone have a large tank upstairs?

you have to keep in mind the garage has 16" on center and a house would have 12" on center. I would consider of putting a brace to beef up the floor and since its on a exterior wall you should be ok. that 4" is alot when deplacing weight..

what sort of brace would you be talking about?

beefing up the floor joists or if you are able to put in teleposts.

FYI, 90% of residential floors are designed to handle 40lbs/ft2 live load, and about 15lbs/ft2 dead load.

It is fairly easy to work out what your weight of a tank/water/equipment etc uses, divide that by the area of the tank, and that will tell you if you are good.

Not sure what teleposts are. Adding more 2x6 studs to the that exterior wall shouldn't be a problem. Do you think strengthening that wall alone will increase the overall load capacity, or would I have to upgrade surrounding walls as well. The opposing wall is 24 ft away, don't think it would help much? Thoughts?

My total weight is to be 2500lb and the total footprint is 2'x6'
So 2500 divide 12 = 208, that 208lb/ft2 the tank is imposing on the floor. Way too heavy according to your numbers, unless I am not getting right?

At over 200lbs/ft2 you will be over weight. With out seeing things up close I can't say what the best way to deal with it.

Your best bet is to have a structural engineer come over and look over things, and give his suggestions. Your wall studs @ 16"o.c. will carry the load, it is the joists & the beams may be the issue.

Where are you getting this from? Just curious because I had an engineer come by our last place and the numbers were WAY different. And he was being conservative.

I'm certainly not an engineer (rather an engineering DROPOUT) but I'd never proceed without jackposts at least under the tank. I'd have them on either side of the tank really.

My livingroom 225 gallon has (5) 2x14 laminated beams under it's rear with a pair of jackposts supporting its front which rest on an 8x3 footing poured beneath the basement floor.

When full i can jump (220lbs I am) next to the tank and I see the FAINTEST ripple. My old 65 gallon used to move quite a bit in my last house on the main floor with just a single set of jackposts beneath it.

Just my 0.02 though. I did this planning before the house was built.

Worried: big tank over garage....need ideas
 

toxic, is that a typo? Because those numbers don't make any sense. 15lb/sqft max. sounds like a straw house limits.

Greenspotpuffer, what numbers did you get from your source, if you don't mind sharing.

The numbers I am giving you are based on my experience as a Residential & Commercial designer. The 15lbs/ft2 is dead load, which is based on the material itself.

The 40lbs/ft2 is the live load, which is people, furniture, fish tanks, etc.

Consider live load to be anything that can be moved, and the dead load the structure it self.

If you need more info I will pull out my building code to verify.

this article might help:

http://www.cichlid-forum.com/article...ium_weight.php

Ok makes sense then :)

My fiance just reminded me that the place I am talking about was an industrial building that had been turned into condos, so way different from a house. He gave us the numbers as roughly 150lbs/ft2. Sorry I should have realized a house is going to be different.

I am having an engineer come to my current condo to take a look but it sounds like a waste of time from what people are telling me because my new place is a ridiculously overbuilt concrete building. Not just the floors but walls are all concrete too.

Does the post below this room have a weight marking on it......it should be on there.

ok...retract my comment...I was going somewhere else with this on a residential note.

Thanks for the link AJ77, toxic's numbers make alot more sense now. I need to evaluate my joist spans and figure out a way to add columms underneath.

I have a 140 G. on the second floor positioned over the cantilever outset for a china cabinet in the dining room. It hasn't shifted in the three years or so that it's been there. Placing the tank against the wall with the joists running perpendicular to it like this:

t a n k

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is the strongest position it can be in and I have seen many large tanks on second floors that way without additional support.

Toxic, your 40lb/15lb per sq ft idea just clouds the issue. It doesn't relate to placing a load in one area of the room. What it relates to is the total weight the room (floor) can bear.
For ex. A 10' x 10' room can hold 15lb's/sq. ft. DW min. 10x10x15=1500. The room can hold 1500lb's DW.
The formula can't be used to work out how much a specific part of the room can hold.

LMAO.... someday Greg! someday, when you least expect it... :mrgreen:

I've got a 180 gal 72x24x24 above my garage as well, I put a telepost under the joist under my tank. It was around $70 at HD. I put it in right before adding water to my tank. No problems at all, great for peace of mind.

This is just the Building Code design criteria, shorter spans may hold more load. Remember dead load of 15lbs/ft2 is based on the weight of material only, not anything else.

I stand by my comment that 2500lbs over 12ft2 is serious overloading a floor based on the building code. Better be safe than sorry.

Again with out looking at the floor I can't say what it can hold exactly, and that is the reason for an engineer. It has been awhile since I have done the calculations.

Oh, and jsut beacuse your floor has not moved in 3 years that you can see does not mean there are no problems. I have seen enough over my 20+ years of experience in design & construction to say be careful.

I'm not worried :)

T, I wasn't questioning your experience, just noting that the numbers didn't equate to the specific problem. There isn't anything wrong with being careful and if it is easy and gives piece of mind to beef things up then it's all good but this type of question arises fairly regularily and for most tanks of that size there is no problem.
I can't recall the last time I've heard of a floor collapsing because of a non custom aquarium actually. I'm sure it has happened somewhere but if it was that close a call I'm sure there would be more incidents.

This week I have serviced a 230G., 300G., 150G., 140G. and a 135G. tanks; all on joisted floors - no collapses so far.

After having a closer look at my floor, I realize the joists run parallel to the proposed tank placement. This could be a problem right? Let me refresh the scenario again. Tank is situated along a load barring wall above the garage where there is a supporting joist and beam that lines up right in the middle of the tank position. The floor joists however runs parallel with the tank. The optional teleposts is no longer an option. I am now considering a 125g tank instead of the 180g first thought. Without additional support, can I just wing it with a 125g.

Since you're worried, get that engineering report, (might PM GreenSpottedPuffer if he'll give you an idea of cost, since he had it done) and figure how to stay big or you'll be kicking yourself later that you didn't.

Can you double up the first joist, expensive but install a steel beam?

Not sure how much room you have in your garage, but if it were me I would build a supporting wall in your garage directly below your tank. Make it floor to floor 12 inch centers with construction grade 2 x 6 and tie it in to the existing joist. If your anything like me you can always use more shelving in your garage ....:biggrin::biggrin:

2X6 to suport a live floor? sounds under code to me and I wouldn't put anything up there. you can sister 2X12's to them or install a metal beem to suport the tank, or use jack posts but that eats up carage space.

Steve

Cannot install telepost because it would be in the way of where I open the car door.

What about two teleposts on the sides of the garage so you can still park inside, and a metal I-beam spanning the distance? (Apologies if this was already suggested, I only just saw the last 2-3 posts here..)

Sistering with 2x12s adds strength without eating any groundspace.

A quick question for the experts and a little bit of a thread hijack..

What is the largest tank suggested for this same situation, if the tank is perpendicular to the joists and on an outside wall..without having to do any "renovations"?

210g on second floor
 

I put my 210 gal + other tanks on the second floor on my house. Assuming that you have 2X6 vertical walls, and that the support beam runs perpendicular to to outside wall, and down the middle on the tank -- I wouldn't worry too much. The amount of weight that a 2x6 can take is not a problem, (thousands of pounds per 2x6 depending on length and grade).

The real problem is the span on the joist. I had a span of 8' between support beams in the basement, which is just too much span with 2x8 joists. So I built a closet under the tank in the room.

There is little worry about "falling" through the floor, the problem is the amount of defection in the floor, or permanent "sagging". If there is a laminated support beam -- and you only come out 24" or so from the wall, you have a LARGE saftey factor with the main supports. Realistically you have 3' hanging out onto the joists, rather than in the middle of the room.

So, if you have 2500lbs, 1250 is on each side. if you hit 3 joists going into the room, you have about 420 lbs on each joists. But because you are only 3' out -- of you have a 12' span on the joists, you are comparable to about 1200lbs on a joist in the center of the span.

I have some calculations for the defection that I'll look up if need be. I planned for approx 1/16" deflection (which is over built) on my floor, and then built the stand using 2X10 beams on the upstairs.

I would be an engineer to properly look at it (and sign off on it for insurance purposes). But, at least -- build a good stand that loads most of the weight onto the beam and outside wall, and if you are really paranoid, sister up the joists (went from 3 joists to 11 because I could) under the tank. And remember that a good grade 2x4 48" will take almost 6000lbs by itself if not allowed to bend. Yes, 1 2x4 can hold a good size pickup in the air....

It's just the span and sag that you need to worry about.


deflection is (5wl^4)/384EI

w = weight per inch
l = span length
E = modulus of elasticity = 1x10^6

I = bh^3/12 (beam/joist width*height cubed/12)


so 2x8 joists

(1.5)(7.5)^3/12 = 52.7

5(3.12)(144)^4/(384*10^6*52.7) = .33 inch roughly

So a quarter inch of defection and that is with assuming the weight is further out into the center of the joist.

you should end up with about 1/8" in reality if you calculate the weight out over the span properly. And that is assuming that you don't have most for the weight directly on the outside wall.....

ok aparently I am all screwed up. If the Garage is unfinnished can you see the joists. the studs arn't to much of a factor as they can hold a house up which is way more than your tank.

Steve

wasn't in the OP the 2x6 studs, not joists.