should I worry about the weight on my old floors?

[Dave-H]

Since I'm getting such good advice from this forum, I thought I'd throw out this technical question about the weight on the floor.

My house is an 1890 Victorian. The location where I want to put my 55 gallon corner aquarium is luckily right next to a load supporting wall. Unfortunately, I can't really see what's underneath that wall because the basement ends on the same side of the wall where the aquarium will be. There is an old crawlspace on the other side of the wall, but it's hard to really get a look at the condition of it.

I can tell by looking at it that it's moved a tiny bit over the years, and the main floor (first) floors are generally not exactly level. To make matters worse, there is a quite heavy refrigerator on the other side of this wall, and hardwood floors underneath the intended location of the aquarium.

I understand that most floors can handle a 55g setup without issue, but I'm a bit concerned about this one. I keep finding evidence of floor problems - the bathroom floor (about 7 feet away) has about 1.5 inches of thinset because someone had to float the floor excessively to get it level. Things like that.

I'm considering buying a couple of jack posts (http://www.homedepot.com/Building-Materials/h_d1/N-5yc1vZ1xhfZaqns/R-100022783/h_d2/ProductDisplay?langId=-1&storeId=10051&catalogId=10053) from Home Depot and installing them to the joists under the tank, just to be sure.

Has anyone done something like this? I don't want to be overly cautious, but I have a bad feeling about this and I want to be kind to this old house!!

thanks, Dave

[Brhino]

a lot of people use jack posts like that, usually for much larger tanks than yours. 42$ is not much to pay for piece of mind that your floor isn't going to cave in and take your fish tank (that you'll probably spend many times that amount of money on over the years) with it. Nobody except a qualified architect/mechanical engineer who could do an actual in-person inspection can tell you with absolutely certainty, so I'd say if you have any doubts, put them to rest with a little reinforcement.

[little hawaii]

Just put some support plates under the legs, like small pieces of plywood. That tank will hardly put out more weight per sq. ft. than you do standing there. Total weight of tank divided by 4 legs; I'll bet it is less than your weight.

[fins_n_fur]

If you have a bad feeling, then you might consider getting a professional home surveyor or better, structural engineer for professional advice.

[Dave-H]

a lot of people use jack posts like that, usually for much larger tanks than yours. 42$ is not much to pay for piece of mind that your floor isn't going to cave in and take your fish tank (that you'll probably spend many times that amount of money on over the years) with it. Nobody except a qualified architect/mechanical engineer who could do an actual in-person inspection can tell you with absolutely certainty, so I'd say if you have any doubts, put them to rest with a little reinforcement.

This comment sort of matches what I am feeling. A cheap but good quality jack with a rating much higher than I need will cost about $50. Two or three of these could provide good support to each of the joists that will be exposed to this weight, and that's pretty good security for $150 bucks.

I have never installed a jack post before but it seems simple enough. My expectation would be that you need to make sure it's plumb with the ceiling, then drill into the basement floor and the joist then screw that sucker in and tighten it up. Could it be that easy?!

thanks again :)

[Northernguy]

All I did was screw two 2x4's together to make a 4x4 long enough to span at least three joists.The pole once set will not move and does not need to be anchored.The weight of the house will hold the jack leg.lol
I set it under the center joist and adjusted the pole to the right height.
Make sure you check first to see what the level of the floor is so you do not over jack the pole.Try not to go past level.

[Dave-H]

All I did was screw two 2x4's together to make a 4x4 long enough to span at least three joists.The pole once set will not move and does not need to be anchored.The weight of the house will hold the jack leg.lol
I set it under the center joist and adjusted the pole to the right height.
Make sure you check first to see what the level of the floor is so you do not over jack the pole.Try not to go past level.

I don't intend to raise/alter the floor at all - it's not quite level, but I really don't want to try and remedy that using a jack pole. That needs to be done properly, so I'm just going for some reinforcement.

I am curious about how much I should load the pole, though. I assume there are instructions on how tight it should be :)