How much weight can my floor take?

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Hey guys,
Firstly, hello - I'm new to this forum, I've recently started keeping fish again - this time I'm keeping malawi cichlids instead of what I used to keep, just community fish and a few tanks of betta's.

I've set up a small tank in my room just to get started, 60litre or so and have a few small malawi's in. I'm not ignorant to the fact they will need rehousing in a few months time and have no problem with that at all. The problem is where I want to put them.

My house was built in 1900 or so, and I'm not sure what sort of weight I can put on my floorboards before they fall through, I'm not much of a DIY guy and quite oblivious to common sense when it comes to being hands on so perhaps this is a ridiculous question.

What's the maximum size tank that would be more than comfortable upstairs in my house? Would 200litre be safe or is that pushing it?
Many thanks,

James

[huma-huma]

Hi welcome to AA!!
Without physically looking and inspecting your house, I'd say 50-75 gallons, perhaps a tiny bit more if you have it inspected. The only problem with your question is that its highly subjective. Depends on what kind/size of wooden beams and even the type of wood they used. Obviously if you put a fish tank in the middle of the room, where there's usually no reinforcement underneath, its gonna bow a lot. Whereas you place it along a wall that has support underneath, you won't see as much bowing. I'd honestly recommend getting a good look at the support beams in the floor if possible. Hope this helps

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Thanks, that'll at least give me a rough idea of what to look for. Perhaps I'll get someone round to have a look for me.

[mfdrookie516]

It would take an inspector, or someone who was very knowledgeable on the subject to determine, but I will say that I'd put money down that a house built in 1900, if in good shape, will hold more weight than a newer house. Back then, they overbuilt... now people just put the minimum to get by on most builds.

[huma-huma]

Yeah I think that's what's of importance, how good of a condition is the weight-supporting structure of the house?

[zparticle]

Odds are good you could park a small car on the second floor of a house that old, if it is in good condition. The key to holding the weight is how the stand distributes the weight. If you put 1000 pounds on a single square inch of space it is a lot different than putting 1000 pounds evenly distributed over 20 square feet.


You could get a stud finder from a hardware store and use it on the floor to determine how far apart the joists are to make you feel better.

But a better way is to determine the total surface area of the parts of the stand that will be touching the floor. Divide that by the weight to determine the pounds/square inch (kilos/square cm). If your floor can handle that load you are good to go.

[tlkng1]

Also, when placing the stand, place it across several joists rather than run it parallel. My house was built in '52 and I know for making changes that the wood is thick and heavy...my father actually burned out a circular saw blade trying to cut through a wall beam to install a bathroom vent fan.

Still, I wouldn't place a tank on the second floor just from things like cracks in the ceiling from the weight of a radiator that has been in the house since the place was built. On the first floor however, I had a 75 parked across 3 joists and ran a reef...so about 150 pounds of liverock plus tank, stand and water. Never had a problem.

Most average floor joists are 16" on center.

[huma-huma]

Yeah my main floor has 10x2 that are spaced 16" on center, handles my 125 pretty good..... Zparticle brought up a very good point. If the weight is evenly spread out over the stand, shouldn't have issues. If its uneven and weighted to one corner or side, could cause issues

[Grizz]

Here's what i do 1st stretch a string across the floor you want it flat the mark the tanks foot print on the floor Now the hard work get some free weights or bags of sand and load the foot print with the as much weight as you can this will show any flex or bow in your floor the string will stay level were the floor will sag

[JimmyA]

Go down in the basement and take a look at the support.

[Mike-words]

Don't chance it have a structural engineer or inspector come out and they should be able to tell you how weight it can take. Then for peace of mind cut that loading in half and have some tele-posts installed carrying all. The way to the concrete slab or foundation. Im helping a buddy get set up for a 375gal on the main floor as well as a 180gal that will only load as is set up one floor joist but that will change

[Sparky74]

The only thing I would worry about with a house that old is possible insect damage that has gone unnoticed. I wouldn't worry so much about how it was built, since back then they had better lumber and normally built stronger than needed.

Do you live in an area prone to termites, carpenter ants(Camponotus pennsylvanicus...You think we have them in PA? ) or powder post beetles? If you have ever had any of those in the past, I would just take a good look around and make sure there are no signs of damage.

[BillD]

I would disagree with an old house necessarily being better built. Construction methods that were use back then wouldn't be allowed today. So, it would depend on the house itself. Just because the floor joists are larger dimensionally, doesn't mean they are well attached or in my old house even sitting on a sill plate or atop the studs from the first floor.

[Vicksta]

I personally would suggest consulting either an engineer or someone with good carpentery skills.

The space distribution will work within limits.

I recently took out a flooring system in a bedroom that the homeowner had a king sized water bed in. It actually broke several of the floor joist. This is also a 100+ year old farm house. So older is not always better.

I understand the weight different is going to be tremendous compaired to this, but you should look into possibly reinforcing the floor, just in case.