Tank size and floor support question
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Paul B
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This is true and that measurement is for the center of the joist. The tank will mostly be resting on the brick wall and maybe only half will be on the joist itself and that is right near the wall.
This is no problem. Everybody who has a tank on an upper floor is on joists and new joists are no where near as strong as those old dimensional lumber.
Blue Collar Reefer
Community Member
The span is the length of the joist from bearing to bearing, a house that old the span is likely much more than code allows today. I know what you’re saying, and I agree that it most likely won’t make the joists fail, especially only being a couple feet in from bearing. But I like to stay on the side of caution. A 180 At 2,000lbs that’s still almost 700lbs on each of the 3 joists it will sit on. I’d hate to see someone’s floor fail because “it should hold”
I am in construction and agree with the statement below that the simple solution is to shore up the floor joists with jack studs, assuming you have room to brace directly down to the concrete floor. Cross bracing between them would be a good as well to add additional supportI'm looking for a new tank and would love some input about tank size and floor support. House was built in 1932 with full basement on concrete floor. Floor joists are 2 x 8, 24 inches on center. The subfloor is 2 x 6 wood planks run on a diagonal (no plywood) and above that is 1 x 4 x 36 wood plank flooring (photo attached....apologies for the cobwebs). I'd be placing the tank against an exterior wall, perpendicular to the floor joists. How big is too big for this floor? At what point should I consider adding additional support? I'd like 180 ish gallons. I've done tons of googling but most references are to new construction. I'd rather have the input of experienced reefers anyway. Thanks in advance.
I don't know if mentioned but ask the opinion of the 2 engineers ever consider a steel I beam with 2 metal jack posts? doesn't sound like it would be unsightly considering your doing a basement sump or you could just hide them. Just a thought
Problem solved. OP only wants a larger aquarium she's not looking to park a truck in the house. This thread reminds me of some of the wood stand threads where it takes four people to move the stand but only two people to set the aquarium on top.
BryanM
7500 Club Member
I like this version better than what I had to do.
Problem solved. OP only wants a larger aquarium she's not looking to park a truck in the house. This thread reminds me of some of the wood stand threads where it takes four people to move the stand but only two people to set the aquarium on top.
Crawling around in the dirt in the crawl space, digging holes, and placing concrete footers with 4x4's. But its done, and I don't worry. Of course the next day I wondered why my abs were sore.
The joists can hold the weight, it’s the bouncing when walking around is what I’d address. Blocking or cross bracing in between joists will help. A couple of added support posts reaching the basement floor would be better
Have been a building contractor and hobbyist for over 35 years
Have been a building contractor and hobbyist for over 35 years
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Gtinnel
10K Club member
I would probably put a tank that size where you want it and not be concerned, but if the area under the tank is unfinished then why not go ahead and add extra support then you wouldn’t have to worry about it.
Maybe it’s hard to tell from the picture but your subfloor doesn’t look like 2x6s to me. They look considerably thinner, although for the weight of the tank it probably doesn’t matter. With the tank spanning several joists they’re what transfer the weight to the load bearing surfaces anyway.
Maybe it’s hard to tell from the picture but your subfloor doesn’t look like 2x6s to me. They look considerably thinner, although for the weight of the tank it probably doesn’t matter. With the tank spanning several joists they’re what transfer the weight to the load bearing surfaces anyway.
BigAl07
Well-Known Member
First off, KUDOS to you for asking and providing some very detailed information. Well done.
I've not read all of the replies so this might be redundant....
I come from the Construction World and spent 2 decades designing Floor & Roof systems and calculating weights. The key to this is to make sure every pound you add is CORRECTLY transferred down into the earth. While a Contractor can probably get you taken care of (120 - 180 isn't a huge weight problem, generally with "Real Wood" construction) you want someone who can accurately distribute the weight and not add any Point Loads or worse, SHEER points.
While we generally see "support beams & posts" added wherever when we add a new tank, I have seen instances where "Jack Posts" were placed and the concrete slab wasn't "adequate". This resulted in a cracked slab and a sagging floor/tank resulting on some MAJOR anxiety and some not-so-fun tank reset. They ended up adding some STEEL PLATES to spread the weight across a large section of the concrete slab after some "slab repair". You just never know exactly what is going on in/under the slab, especially in an older home when building codes/inspections were much less stringent.
Good luck and we can't wait to see what you come up with and please update us as to what you find out in your research etc. Don't be afraid to spend a few hundred $$ for some extra peace of mind. It's $$ well spent!!
I've not read all of the replies so this might be redundant....
I come from the Construction World and spent 2 decades designing Floor & Roof systems and calculating weights. The key to this is to make sure every pound you add is CORRECTLY transferred down into the earth. While a Contractor can probably get you taken care of (120 - 180 isn't a huge weight problem, generally with "Real Wood" construction) you want someone who can accurately distribute the weight and not add any Point Loads or worse, SHEER points.
While we generally see "support beams & posts" added wherever when we add a new tank, I have seen instances where "Jack Posts" were placed and the concrete slab wasn't "adequate". This resulted in a cracked slab and a sagging floor/tank resulting on some MAJOR anxiety and some not-so-fun tank reset. They ended up adding some STEEL PLATES to spread the weight across a large section of the concrete slab after some "slab repair". You just never know exactly what is going on in/under the slab, especially in an older home when building codes/inspections were much less stringent.
Good luck and we can't wait to see what you come up with and please update us as to what you find out in your research etc. Don't be afraid to spend a few hundred $$ for some extra peace of mind. It's $$ well spent!!
Marco_99
Well-Known Member
This is all correct. People are very shortsighted to looking at a situation when you have that kind of an odd dead load stressing a floor for years, it will take its toll on a normal structure over time. Your house structure itself in different climates moves. Floors expand and contract, foundations can settle or shift, roof trusses lift, materials degrade, wood shrinks and expands, all these things happen in a building structure just due to climate and time. When you build a house, you take measures to try to counter or control these things from happening. It goes the same for putting an abnormal dead load in the middle of your house. It to overtime will have a cause and effect on your house. Holding the tank up isn’t at question, it is two years down the road do you want your floor sagging 3 inches? Do you want your ceiling cracked out on the ceiling side wall? do you want your foundation below it cracked or settling under weight? That is what you’re trying to get ahead of by taking preventative measures now. Your house and materials chosen weren’t designed at the time to have an extra 2000lb + dead load sitting inside it. It’s never a problem, until it’s a problem, and usually at the worst timing and triple the cost.
Skywater
Community Member
You have very nice flooring to begin with. The boards are in good looking shape.I'm looking for a new tank and would love some input about tank size and floor support. House was built in 1932 with full basement on concrete floor. Floor joists are 2 x 8, 24 inches on center. The subfloor is 2 x 6 wood planks run on a diagonal (no plywood) and above that is 1 x 4 x 36 wood plank flooring (photo attached....apologies for the cobwebs). I'd be placing the tank against an exterior wall, perpendicular to the floor joists. How big is too big for this floor? At what point should I consider adding additional support? I'd like 180 ish gallons. I've done tons of googling but most references are to new construction. I'd rather have the input of experienced reefers anyway. Thanks in advance.
When I added reinforcement under my tank, I aimed for extra heavy duty. I added sister joists to all the existing joists...even a little beyond where my tank and stand sat. I removed the diagonal bracing in between the joists and added full width 2 X 8 lumber bracing in between (perpendicular) to the joists. When adding the bracing I made sure that extra braces lined up with the edges of the aquarium stand. Three ten foot long 2x6s sandwiched together run perpendicular and under the joists. 4 basement support jacks run from this to the cement floor. Extra heavy duty adds piece of mind.
leeloo82
Community Member
Where is everyone finding these great deals on structural engineers? I've called 3. Most engineers are quoting me $1000+. Cheapest one was $600 but that's if I didn't need an official report of what needed to be done to provide to contractor (if I did need to reinforce my floor). I called a flooring/repair contractor who said I might as well take that money and pay him the $450-500 to just go ahead and reinforce my floor whether I need it or not, lol. Kinda good point. My tank is a Waterbox Infinia Frag 175.6 - so estimate 1800 lbs after water & rocks, etc.
well probably has to do with any insurance claim in the future. would have to get an engineers stamp if building new I would assume. So if you would be comfortable parking your car there you are golden lol
That's probably about right to have Structural Engineer look at a change to a floor plan. I recall having one do a plan for a beam in my basement and to draw up a set of plans was about $500 and to submit them to the County was an additional charge. They were stamped but this price was about 10 years ago. Most floors will hold more than the design weight, however the main problem putting a heavy Tank on a floor not designed for one would be sagging.
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