Should I add support to my floor?

Jakepen · Jul 30, 2017

Tank is going up agains a wall in my living room, hopefully will be around 200 gallons total volume, with all the rock sand and stand looking at over 2000 pounds. Went into the crawl today, and the joists are running not parallel with the tank, so the "correct" way. I'll post a picture, that tank will be going right around where those blocks are located.

TheLadyCrash · Jul 30, 2017

IMHO, I would have a contractor come out and evaluate. They should come out and give you an estimate for free.

pdxmonkeyboy · Jul 30, 2017

If that picture is below your tank.. Save your money, you have the main structural beam running right there! You could put two tanks that size without additional bracing.

(I'm a professional contractor who is well versed in structural calculations and just installed supports for my new 240).

Cheers

pdxmonkeyboy · Jul 30, 2017

Oh.. if it is up against the wall then crawl over and see how your floor joists are attached to the rim joist. In older homes sometimes they are just nailed in. If that is the case then go to home depot and buy joists hangers and a box of tico nails and install the hangers. Google it.... childs play.

Jberge · Jul 30, 2017

The joists are on top of the beam so you don't need hangers. Although I would see if those blocks are on an actual footing or just a thin slab sitting on the dirt. If it is a footing and with the fact that there's the tripled up beam you should be good.

Jberge · Jul 30, 2017

Those joists are on top of the beam and should be on the foundation along the exterior so you shouldn't need hangers. Although I would see if those blocks are on an actual footing or just a thin slab sitting on the dirt. If it is a footing and with the fact that there's the tripled up beam you should be good.

Jberge · Jul 30, 2017

My bad on the double post

pdxmonkeyboy · Jul 31, 2017

So no hangers if the joist are on top of the beam... even if it is several feet away?

Jberge · Jul 31, 2017

pdxmonkeyboy said:
So no hangers if the joist are on top of the beam... even if it is several feet away?

Hangers can only be used if joists are attached to the side of the beam. I'm not sure what distance you are talking about though

Jakepen · Jul 31, 2017

Throwing a lot of terms my way I don't quite understand guys haha. I appreciate the replies. I'd be surprised if a contractor would come out for free, or is that a thing?

Idoc · Jul 31, 2017

I really doubt a contractor will come out for free to just check if your supports are adequate. They might come out for free to give you an estimate for work, though... which is exactly what they are going to recommend to get paid something, lol.

If your tank will be sitting directly on top of that triple beam, then I don't see what could be better... plus you are saying that the joists are running perpendicular to the wall (and direction) of the tank...pretty ideal situation. Take a picture under the house EXACTLY where the tank will be sitting. You are getting some good contractor advice in your thread already, but unless you show them EXACTLY where the tank will be sitting, all they can do is give you guesses.

Jberge · Jul 31, 2017

Jakepen said:
Throwing a lot of terms my way I don't quite understand guys haha. I appreciate the replies. I'd be surprised if a contractor would come out for free, or is that a thing?

Idoc is right, they will not come out unless you tell them what you want done so they can give an estimate. Sorry for confusing you. What I was saying is, can you see how thick the concrete is under those cinder blocks and report back

Jakepen · Jul 31, 2017

Yeah I'll get back under there tomorrow. Anything else I should look for and take pictures of?

Jberge · Jul 31, 2017

Jakepen said:
Yeah I'll get back under there tomorrow. Anything else I should look for and take pictures of?

A rough estimate of how long that beam is might be helpful also

Jakepen · Aug 1, 2017

Jberge said:
A rough estimate of how long that beam is might be helpful also

Which beam exactly, this one?

Jberge · Aug 1, 2017

afish4u · Aug 1, 2017

IMHO I don't think you have a single good answer on here. Just because your looking at a picture and see a 3-ply beam doesn't mean squat. If there is a 3 ply beam there it's there already for a reason why else increase cost.
Some questions that haven't been asked yet.
1 what is the depth of the beam?
2. By chance is any stamps on the beam for product and grade?

3. Total length of the beam and were is bearing located along the beam.
4. How long is the tie-in span of the joist from both sides of the beam.

Any chance u can draw up a floor plan of what you have for an existing floor?

Is the tank going to be placed on the beam or the floor near the beam?
I would also look at depth and spacing of the floor joist near by.

I'm assuming everything is dimensional lumber for the floor that we don't see also?

I will try to check back here later.

knowen87 · Aug 1, 2017

I have a hard time with these posts sometimes. I am a structural engineer and I feel like some people are so freaked out that they spread the fear around. Here is what you need to know. If your tank is 6ft long and it runs parallel to the beam (the one that you have the x on above) and sits within a few feet of that beam, you are fine. You will be sitting perpendicular to the joists (the ones going side to side in the photo) and close to their support. Pm me if you are still concerned and I could explain it more. To me, this is a slam dunk as far as placing a tank and the only better option is to be on a concrete floor. Standard residential floors are designed to have variable (live) loads. It is likely that the beam is designed for 1000lb per foot or more. If it were my house I would not be concerned.

afish4u · Aug 1, 2017

Wow really not to get into an argument with an SE but run the calcs. 1000 plf would put you at a 3-ply 14" lvl with l/240 deflection criteria. Figuring 10 clear span That doesn't look like a 14" lvl. Whole the floor may be fine always check the beams. Residential live loads 40psf and dead is usually 10psf on top My post is first to get accurate information. Before makeing a response. Now you ask what do I do? I design roof's and floors all day (14 years). I prefer to make sure I will have a solid complete floor and reduce deflection to prevent to much vibration in a floor. I look at reducing stress for my animals in the tank as well.
I won't continue on a rant here but if this SE will stamp his information for you then your in the clear.

knowen87 · Aug 1, 2017

Sounds like afish4u knows what he is doing. If you want to follow up with him that is fine. You can look as spans, and grades of lumber and do the calcs for the floor and foundation but I have a feeling you will come to the same conclusion.