Weight and Floor Issues

[nacl-man]

Hey All,
My wife and I are (finally) moving into a townhouse and getting out of our apartment (insert cheers here), it's why I haven't been on in months.
The good news is I actually get to build my "dream" tank now, but I'm concerned about weight. How do I find out what sort of weight my floors will support? What I really want is about a 75 gallon reef tank, should I be concerned about this? Most of the problems I have read about are regarding 200 or 300 gallon tanks.
Thanks in advance for your input. Now I just have to deal with moving the current tank w/ out killing anything
Cheers!

 

[dreeves]

How old is the building?

 

[krowleey]

75 gallon will be fine on wood floors.

 

[tony detroit]

I run a 180 plus a 40gal refuge below and I have no problems.

 

[nacl-man]

Originally posted by dreeves
How old is the building?
thanks for all the replies!
The house was built in 1991.

 

[krowleey]

LOL 1991? you have no worries. you can prolly put a HUGE tank on those floors then.

 

[nacl-man]

Awesome! I read horror stories and did not want to loose what is going to be a huge investment in time / money.
Thanks again!

 

[zafirablanca]

We just looked for the direction of the floor joists and load bearing walls, and made out decision from there. Worked out fine so far with a 125 gallon tank on wood floors. House built in 1924.
Have fun!
-Christine

 

[slofish]

Only thing you would really have to worry about is the amount of surface area your stand has. If your stand is resting on only a couple of legs, youre gonna have a problem, but if you have a normal stand that has wood touching the floor all the way around the base, you'll be fine.
As long as the weight is being distributed, you wont have any massive force on the ground at any single point.

 

[dreeves]

Your floors will hold it just fine...I believe the standard is 500 pounds per sq foot or something like that...

 

[mr. ray]

I live in a mobile home. I asked a guy who sells home if my home would support a tank. he said that the floors will hold waterbeds so there should be no problem.

 

[dreeves]

The thing with waterbeds is they distribute the weight over a far larger area then an aquarium will...but even with that..if it is a newer mobile...somewhere after like 1975 or so (check your local codes)..it should still be up in the 500psf range...

 

[mr. ray]

its a 1999

 

[dreeves]

I would better guess it to be fine. Do you know what size your floor joists are?

 

[mr. angelfish]

Originally posted by dreeves
I would better guess it to be fine. Do you know what size your floor joists are?
The joists (upstair) seem to be 2 by 8 and length unknown, a foot aparts, and all of the upstair is covered with plywoods and hardwood as it was put on in 1969.
How much weight per sq foot it can hold? How big (max) tank I can put upstair? Downstair, Havent measured under crawlspace but as I can tell that it is somewhere 2 by 12. The floor is covered with carpet or vinyls. No hardwood on the first floor.
Hope someone can answer my question. Thanks.

 

[eric4usa]

I have my tank over my crawl space.
I placed 16" square slabs (used for outdoor walking paths) on the ground as it's basically dirt covered with plastic/carpet.
I measured and cut 4x4 studs to go between the joist and the slab. (I cut them slightly shorter, like 1/2 inch or so)
Then used shimms on top between the joist and the 4x4 stud, which just sits on the slab.
I placed 3 of these studs at what I felt were important points in the joist structure to make the joists rest on the studs, rather than the metal hanging brackets.
It really firmed up my family room floor above.
My test was to jump around like an idiot over the area of the studs, this was like jumping on concrete and made no noise/vibration.
Jumping 10-15 feet away made a booming noise like any idiot jumping around would sound.
It kinda made me want to reinforce the entire crawl space area, but didn't do it.
When I placed the tank it's self, I cut a piece of 3/4 inch plywood in exact shape of the tank for it to sit on to somewhat disperse the pressure from the 4x4 stud frame of the stand.
This was all probably overkill, but I have no worries about my floor sagging etc. and it cost about $5-10

 

[dreeves]

Even with a give rating of 500"psf...you could possible encounter sag if the span is too wide...
If the joists are 2x12's...16 inches or so on center...you will be fine. Even with true 2x10's (true being non dimensioned), I still put a brace in the basement below.
I do not know what the tank size limit would be...if you are in a mobile without a basement...then it would be very easy to support the floor beneath any size of tank you wanted...a cement footing and a couple of short jackposts...

 

[bridge man]

Just place the tank next to a wall with a load bearing wall beneath it. That way you will have no deflection problems at all. The joists will be carrying the load via shear and very little moment. Don't worry about placing any plywood under the stand to help disperse the weight as it will not do this very well. When you place a point load onto just about any material in which the load will cause compression, then the load will transfer into the material at an angle of roughly 45 degrees until either it runs into the edges of the material or it reaches the support. Not picking on anybody, but in eric4usa's case, this means that instead of the load resting on 12.25 in^2 of area (3.5"x3.5", dressed 4x4 size), it will be on 18.06 in^2. Not enough to even worry about doing it.

 

[rane]

very well said bridge man. so my question is. on the new constructions whats the bigest tank I can have in my home?

 

[mr. ray]

I don't know how far apart the floor studs are but the floor dose have plywood and not partickle (sp?) board. Like i said the guy who sells them (the houses) said there should be no problem.