I have a 320 gallon 8X2X32" tank, that is very heavy, bottom in an inch thick plus water and sump. I bought 3 floor jacks, concrete forum bases and a 4X6, I was going to run 3 supports. My joists run parallel with the tank. Well once I cut the plastic and removed the insulation I realized only 1 joist is under the tank, right in the middle. I only have the stand built and really dont want to change the location. I have 2 ideas, I could add supports between the floor joist and then run a 4X6 with 2 jacks on the front and back of the tank, or not add the supports and put the 2X6 directly on the subfloor. Either way I will have a 4X6 on the front and back 8' long with 2 jacks on a concrete forum. I can also add more plywood on the subfloor if that helps
Suggestions on floor support
- Thread starter Niners4952
- Start date
Hello; I will include a link to a discussion about floor support. It is an interesting read but more to the point there are some good pictures of such things as blocking.
A 320 gallon tank with all equipment, water and substrate may weigh around 3800 + pounds.
You have the least desireable situation with only one joist directly under the tank. One thing I would do is to try to sister a new joist on each side of that joist. That may prove difficult to do if there are plumbing and or electrical runs in the way. Sistering can be very difficult under good circumstances and sometimes is not possible.
Blocking is another thing I would try to do with or without the sistering. Lots of blocking to spread the load to the other joists.
Setting up some support columns under the floor will likely be a must in addition to the sistering and blocking. It is very likely best (crucial) to try to do the support work before setting up the tank.
Good luck
A 320 gallon tank with all equipment, water and substrate may weigh around 3800 + pounds.
You have the least desireable situation with only one joist directly under the tank. One thing I would do is to try to sister a new joist on each side of that joist. That may prove difficult to do if there are plumbing and or electrical runs in the way. Sistering can be very difficult under good circumstances and sometimes is not possible.
Blocking is another thing I would try to do with or without the sistering. Lots of blocking to spread the load to the other joists.
Setting up some support columns under the floor will likely be a must in addition to the sistering and blocking. It is very likely best (crucial) to try to do the support work before setting up the tank.
Good luck
Hello; One last thing. Any suggestions you get on this forum from me or others should be checked out by a professional. Someone knowledgeable about structure and able to evaluate the particular conditions. An engineer would be my first choice. Perhaps a good contractor. I am not on the scene and any suggestion I make is pure speculation and not supported with enough information about the specifics of your structure. Some one with knowledge needs to have an actual look at the situation.
If you are not familiar with concepts such as sistering, blocking and such and have not done that sort of work before, get a professional in.
Having the tank perpendicular to the joists seems likely to be a better way to go and is usually suggested by most.. Consider a different location.
If you are not familiar with concepts such as sistering, blocking and such and have not done that sort of work before, get a professional in.
Having the tank perpendicular to the joists seems likely to be a better way to go and is usually suggested by most.. Consider a different location.
thanks for the response, if I were to sister the joist would it just have to be the length of the tank or maybe a couple feet longer? Was thinking of sistering the 3 joist 10 feet and add blocking then 3 4X6 beams running the opposite way with the floor jacks
Hello; That is not my understanding of how sistering is best done and my take is this will be risky. When I sistered some floor joists in my current home the new joists were almost the same entire length as the original joists. This was from the outside load bearing wall to the center load bearing beam. About fourteen feet if i recall correctly. It was quite a chore and I did not have any plumbing to deal with and only a little electrical to re route. I also had a full basement height in which to work.
I suppose you are thinking of doing a short sister and having several verticle supports at the ends of the short sisters? I do not know if this will be possible to do in a sound way. The devil will be in the details. This is where I still strongly suggest that you get a professional. This is enough weight that you really need to know what you are doing to get it right. I cannot give you an answer on this forum.
Are you still thinking of placing the tank parallel over a single joist? If so it seems likely that you are going to have to build up some sort of a good reinforcement type cage that gives support under the length and width of the tank and catches the floor beyond the single joist. Even with full length sistering on both sides, a single floor joist does not seem to me to be enough to support the weight. I simply do not have enough information to give a sound suggestion. There are too many variables that only someone actually there can evaluate.
Do you own the house? If so the risk will be yours.
Bottom pic shows tank is centered over 1 joist, my idea is to sister all 3 joist, then add alot of blocking to combine all 3 joist, then run 2 3' long 4x6 beams with 2 floor jacks rated at 18k pounds each on each beam with a concrete forum on the bottom of each jack. A total of 4 jacks
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I do own the house and in the link provided it said sistering for an aquarium does not have to be full length to be effective which is why I would use blocking support as well
Hello; I follow what you plan in general. I have not tried such myself so cannot offer any useful comments. I have mostly found that when doing something for the first time I sometimes make fundamental errors due to a lack of understanding about all that is involved. The concept is easy to picture, I just do not have any practical knowledge in terms of what to look out for.
I do not doubt some sort of good support can be had. Good luck.
I do not doubt some sort of good support can be had. Good luck.
