SubFloor

[sgt_slaughter]

I'm about to go from a 125 to a 230 or 280. I'll be pushing well over a ton at that point and am just looking to for someone with experience to say if my floor should be ok or not. I have no reason to think it wouldn't but would rather check now rather than find out the hardway.
The house was built in 2003, the joists are perpendicular to the tank and the tank will be close to the outside wall.
If this isn't enough info let me know.

 

[cr500_af]

I'm no structural engineer, but you'll need to also note what size lumber the floor joists are, and what their unsupported span is.

 

[sgt_slaughter]

Good call, the span is 13' and the joist is plywood capped with what appears to be 1x2's to appear like an I-Beam.

 

[giulianom]

I would also suggest hiring a structural engineer to come out and inspect the structure.

I had one come out, cost a few hundred dollars but what I got out of it was an analysis and improvement plan with drawings.

Then I DIY'd the reinforcements, using laminated veneer lumber for strength.

 

[reeferman]

thats a TGI joist and that should be plenty strong enough.

 

[wbrown]

the math works out to about 280 lbs per square foot, which translates into about an average overweight human.
The description sounds a lot like a TJI joist, more info here: http://www.homeconstructionimprovement.com/selecting-tji-floor-joist-sizes/">http://www.homeconstructionimprovement.com/selecting-tji-floor-joist-sizes/</a>

The joists themselves should have little issue bearing the load, however you may experience deflection or 'bounce'. Adding another TJI joist at 90* to the existing joists between the tank location and the remaining portion of the room should alleviate this.
The space between grade of soil under your house and the bottom chord of the joists will dictate what options are available to support the joist. There are screw-jacks, Concrete block piers, and cribbing of lumber options. One thing to consider if you have to place concrete foundation pads is to get a termite retreatment in the disturbed area.

Most joist manufacturers will label their 'brand' somewhere on the joist, you can google the name and likely get a table that will define the load carrying ability of your joists.
If one is not apparent, snap a photo and take to a lumber yard for them to identify or post here and I'll see if it looks familiar.

 

[reeferman]

solid advice there Wayne

 

[wbrown]

reeferman;725320 wrote: solid advice there Wayne

Can't believe ya beat me to it though.. got to work on my timing.:doh:

 

[grouper therapy]

How tall are the joist? How far apart are the joist? What room is the tank in ? What level is it on? Anyway to post some pics?

 

[sgt_slaughter]

Thanks for the good advice guys. Not exactly what I was hoping to hear but solid advice I'll follow up on regardless.

The joists are 12" tall and appear to be 24" apart. The tank is on the first floor with a basement below. Pic are from the basement directly below tank.

 

[reeferman]

if theyre 24" apart,i would definitely put more support in there.floors are typically put on 16" center.

 

[grouper therapy]

Where are you located?

 

[sgt_slaughter]

Kirkwood. It's a neighborhood in the city in Atlanta between Little Five Points and Decatur

Edit: They appear to be either the TJI 360 joists.
Used the link Wayne posted above.

 

[sgt_slaughter]

I have some 6x6s here that I could use as posts. Y'all think I could just use a 1x12 as the perpendicular cross beam under the joists?

 

[reeferman]

with a couple of 2x10s glued and screwed together,you could make a drop sill underneath the tank area

 

[basscyn]

What do folks with waterbeds do?:huh:

... never really thought about it.

 

[giulianom]

BASSCYN;725972 wrote: What do folks with waterbeds do?:huh:

... never really thought about it.

Make poor decisions?

 

[sgt_slaughter]

I'm not sure but I think it comes to a matter of surface area.

For the sake of argument let's say the tank and bed are both the same volume of water.
Bed frame would be around 5'x4' for a surface area of 20'
Whereas a tank would be 6'x2' for a surface area of 12'
Same weight of water over almost half the amount of space making it more of an issue for fish.

Although I don't want to take away from the "make bad decisions" hypothesis as I think that has merit as well.

 

[grouper therapy]

I have no doubt that the floor system will hold the tank especially where it is located. I am concerned as some others were that it might add to the deflection of the whole floor.

 

[sgt_slaughter]

Thx Grouper that is a relief.
So for the added support should I put the drop sill directly under the tank or just in front of it?