Basement reinfocement

reefwars · #1 12-06-2011, 05:57 AM

another option would be to build a raised platform that your tank sits on, say 2-3' in width beef it up so the joist runperpendicular to the joists in your floor, then youl span both joists with lots of support so no sagging.you can even then tile it or match it to what you plan to do with your stand .you wouldnt have to do anything like moving plumbing or ducts and you can still have a normal sized stand

Coleus · #2 12-06-2011, 06:06 AM

yeah the subfloor is 1.5 inch thick. I can't increase the size of the stand because 13 inch is

width i can play with. The tank is there to divide our living room and kitchen.I think i will probably put some beam between joints so my wife can sleep at night better (not me lol)

Seth81, what formula are you using to calculate the PSI, my tank foot print is 120'' x 13'' to be exact? Tks

sphelps · #3 12-06-2011, 06:23 AM

He went with the assumption your tank was 20" wide and 13" tall like I did

120x20 = 2400sq sq inches
He assumed 2000lbs of weight
psi is pounds per sq inch so 2000/2400 = 0.83psi

With 120x13 and a more realistic weight of 1500lbs you're at 0.96psi

Happy wife = happy life

Coleus · #4 12-06-2011, 06:25 AM

Thanks and what is the max psi rate of the floor?

sphelps · #5 12-06-2011, 02:42 PM

It's actually slightly more complicated if you really want to get into it. The structure supporting the floor has a minimum requirement for weight but it's based on the actual room size and it's 40lbs/sqft.

It works like this, if the room is say 20 feet by 15 feet that's 300 sqft. Multiply that by 40lbs/sqft and you get the minimum load rating for the room which in this case would be 12000lbs. So that means the floor structure must support 12000lbs total room weight and as far I as I know that's only dead weight so there is additional safety for live weight. This is also a minimum and most house exceed this rating.

When it comes to adding concentrated weight like from say a fish tank you still need to think it through a little as the above formula certainly doesn't mean you can stick all that weight in one spot. However in your case it's not an overly large tank and it's very long so the weight will be distributed quite well.

Now your tile may have a max psi rating but it will be far beyond what your tank will do. You can drive a car on most tile.

reefwars · #6 12-06-2011, 02:48 PM

Quote:

Originally Posted by sphelps

Now your tile may have a max psi rating but it will be far beyond what your tank will do. You can drive a car on most tile.

yup as long as it isnt a pivot point tile can carry an amazing amount of weight, like said you can drive a car on it, ive done car dealships whee you can drive multipe cars right over it and into showroom not to mention car lifts, ive seen zoombooms carrying huge amount of weight as well(provided its set right)

mike31154 · #7 12-06-2011, 03:58 PM

So the plan is to have a FOWLR directly underneath the new DT & eventually move the sump to the basement? Might as well bite the bullet, move whatever ducting & plumbing you need out of the way in the basement and build a fishroom. Have one of the walls of the fishroom run perpendicular to your joists & the 2x4s will provide added support to your main floor. That's pretty much my plan, I already have the fishroom walls roughed in in the basement.

I prefer photos over drawings if possible, then there's little doubt about what the structure looks like. If you can save or convert a jpg photo to bmp format, you can mark it up using MS Paint. Then save again as jpg to keep file size reasonable.

I keep seeing the statement 'if the house is new...'. What's up with that? My place was built in the late '50s and as far as I'm concerned the floor joists & supports are more than likely better than some of the construction I'm seeing out there these days with 'engineered' floor joists. These things scare me, since they are thinner than solid wood joists and made of scrap wood wafers glued together. I sure hope that glue holds for 50 plus years, like my solid joists! Laid diagonally across my joists are ship lapped 7 inch wide solid wood planks and plywood/flooring on top of that. I find it's more about maximizing profit in construction now and many builders will tend to cut corners. Not saying that's the case with all builders, but let's try to look at each case individually rather than making sweeping inferences about home age affecting how we go about solving a problem. Anyhow, that's my rant for the day.

I would add my voice to those recommending you remove the tile under the tank. That area will be unseen anyway and you'll find it easier to open the floor for drain & return lines from the basement. Leaving them there will be a waste of tile. Replace it with a section of exterior grade plywood. I'd even take a little more tile away & have a border of some other material around the stand.

Here's a photo of my future fishroom in the basement. I haven't bothered marking it up with paint as per my above procedure, but it's pretty straightforward. Foundation wall on the right, which I primed & painted with good quality concrete paint. Left of photo shows the last 2x4 of the wall I put in opposite the foundation. Decided to use pressure treated lumber for the 2x4s that are the base of the walls laid along on the basement floor. I don't plan on any floods, but without a drain in the basement floor, if it happens, these will hold up better than standard lumber. My tank will also sit parallel to the floor joists & serve as a room divider between kitchen & dining room. So the wall on the left will add support & help minimize main floor deflection. Take into account that there is often a crowd of folks standing/walking around our display admiring it. Depending on the size of your friends, there's the potential of quite a bit of additional weight around your display. And if it's a high traffic area, continued flexion may contribute to material fatigue over time. No harm in overbuilding something, peace of mind is a good thing.

StirCrazy · #8 12-06-2011, 07:46 PM

Quote:

Originally Posted by sphelps

It's actually slightly more complicated if you really want to get into it. The structure supporting the floor has a minimum requirement for weight but it's based on the actual room size and it's 40lbs/sqft.

It works like this, if the room is say 20 feet by 15 feet that's 300 sqft. Multiply that by 40lbs/sqft and you get the minimum load rating for the room which in this case would be 12000lbs. So that means the floor structure must support 12000lbs total room weight and as far I as I know that's only dead weight so there is additional safety for live weight. This is also a minimum and most house exceed this rating.

When it comes to adding concentrated weight like from say a fish tank you still need to think it through a little as the above formula certainly doesn't mean you can stick all that weight in one spot. However in your case it's not an overly large tank and it's very long so the weight will be distributed quite well.

Now your tile may have a max psi rating but it will be far beyond what your tank will do. You can drive a car on most tile.

all good points but missing one important thing. deflection. floors for tile have to be braced up (by various methods) to decrease the amount of deflection. this is one of the biggest shortcuts builders take, by not doing the required work to stiffen the flor system to lower the amount of deflection in the floor. the result of this is most comenly cracked grout lines and tiles. by putting a larger then normal load in one area you are creating a situation where deflection is increased. to me this is more of a concern than the actualy weight of the tank. if you had carpet floors you would be fine as is I would guess as Sphelps has hinted at, but my concern is the extra deflection the tank weight would cause.

another idea (not sure if it is feasable or not,) would be to run two 2X10, parallel to the foundation wall at equal distances between them. then put two beams to suport them. this would not rely on a slab point load but would drop your celing hight 20" in that area. if you are putting a tank in that area it might not be a concern as you could make the tank a built in and it would just be your fish room that has a lowered celing high if I am understanding the size right.

there are probably 10 ways to skin this cat, best bet would be to find a local person, who even if you have to pay 100.00 bucks. to give you there opinion. maybe talk to a couple good builders and ask them what they think you would have to do, make sure you bring up the tiled floor and deflection concerns.

Steve

sphelps · #9 12-06-2011, 08:18 PM

with 1.5" thick subfloor and 16" joists span a 13" wide tank simply won't cause enough deflection to damage the tile. Also that load rating I mentioned is based on deflection not failure.

Seth81 · #10 12-06-2011, 04:41 PM

Quote:

Originally Posted by Coleus

yeah the subfloor is 1.5 inch thick. I can't increase the size of the stand because 13 inch is

width i can play with. The tank is there to divide our living room and kitchen.I think i will probably put some beam between joints so my wife can sleep at night better (not me lol)

Seth81, what formula are you using to calculate the PSI, my tank foot print is 120'' x 13'' to be exact? Tks

Just take lbs and divide it by the area (in inches square or ft square, whatever you like)