Question for Construction Experts

jfro

New member
Hi.

I want to install a 250 gallon in wall reef tank. The display view will be in my living room but the bulk of the tank and the supporting equipment will be in an adjacent bedroom. The system will be approximately 500 gallons when everything is set up.

I need help finding a place to get detailed instruction on how to reinforce the wall (it's not a load-bearing wall) and how to reinforce the floor (which is over a crawl space). With the money invested in the tank I can ill afford a contractor. I don't mind over-reinforcement. Any suggestions?

Keep in my mind that I'm not someone who will be able to solve mathematical weightload & distribution equations. I need someone who can say do this, do that. I follow directions very well.

Thanks everyone. If I get the right direction you'll see me posting on the Large Tanks forum soon enough.
 
hi there :) hope i can help? but i need to know which way your joist run ,do you allready have a center beam stuff like that .the more you can tell the better i can figure it out for you ..
 
If you are directly over a crawl space, I would go under and find the exact layout of your tank on the underside of your subfloor. Using cement blocks build a couple piers from the ground to the underside of your subfloor directly below your tank. This way you have direct support from your tank to the earth.
:)
 
OK, where to start.... Well first off, just like sawman said, we need to know what the layout ouf your girders and joists are, and how much of a span each are supporting. Then we will need to figute out where in relation to the girderd the tanks will be located and the lay out of the room. once we determin these factors, we can do a few calcs and beef up your under floor. Oh and how tall of a crawl space do you have?
Let me know,
Aaron
 
are both tanks going to be in the same foot print?

your looking at about 5000 pounds once you have everything in the tanks..

joist direction will play no role in the equations...just thier size and spacing. plus the proximity of the tank to the header/ beam/ or column below...but even those parameters dont matter all that much..since a typical floor joist is generally 2x8...therefore, only the spacing will be an issue. and it is also likely that this is an older house with joist set at 16" O.C.

so the only real question is; is your crawl space finished or not? do you have a concrete floor or no? i mean? if you have a soil floor then i would dig some nice holes in the corners of where you plan on having the tank...

as a construction guy i would personally go about 16 inches by 16 inches by 8-10 inches thick...you dont necessarily have to dig if the soil in you crawl space is undisturbed but that is unlikely so dig some holes and tamp the poop out of them...fill with concrete...wait a week...

go get yourself some 6x6 posts or 8x8 if you fell like overkilling it. some 2x10's and a boat load of nails..

depending on tank dimensions...basically make yourself a couple header beams...by nailing (laminating ) two 2x10 together at what ever the width of your tank is plus the next closest joist to either side of it..hang the laminated beam to the bottom of your existing floor joists (obviously going perpendicular to them) directly above your concrete slabs...once they are hung you can measure how long the posts need to be from the bottom of the joist to the top of the slab...you can even place a piece of 2x10 on top of the slab and then measure to that...then cut the posts about 3/16 to a 1/4 longer then the need be (unless there is a tile floor above, then only make it about a 1/8 of an inch longer..)

simply centre the post on the beam and then hammer in the bottom , this will slightly pre-stress your floor. by adding the 2x10 plate on the cncrete you will help dispurse the weight a little more, plus you can put a piece of plastic under the wood to make sure it doesnt rot, or use pressure treated wood...but since i have been in business it has been a no no to use PT inside a house..laws maybe different where you are though..

now you are going to also have to tie the ends of the beams to each other, i would use screws for this to avoid moving the beams and such with hammering...you may even wish to tie the bottom of the posts together to prevent them from kicking out...if everything is plumb the chaces of a 2' post kicking out are pretty slim...but it wont hurt...especially if you werent able to tamp the post holes very well...

IF your floor is finished then you can bascially do the same thing to the floor...but along the concrete floor you will have to put a vapour barrier where the posts would touch, and it would also be a very good idea to essentially frame the posts as walls...that way the wieght of the tanks is carried out through the length of the tank onto the 4" floor rather then directly down...which will undoubtably break right through the concrete floor..

hope that helps...sorry for the huge long post..
 
sorry for beening so late i was working at my sons place building a beem for his basement ...as far as this nanoreefbe !!!!!!!...what the heck is he talkin about about the joist have noting to do with your problem .if the guy had half a brain .not saying i do ,he would soon find out it would ..as far as your crawl spaceand beening done or not .oh gEEEE ...my word !!! it's a crawl space how can it be done ????....it's full of dirt !!!!!!!!! ....give me a beak !!!!!!!!...if you want someone WHO!!!!!!!!! knows what there talkin about e-mail mail and i'll answer all you questions....soory for beening so how do i say it .a pain in the butt .but i know what i'm talkin about ..
 
LOL

first of all:
not all crawl spaces are dirt! Mine is, my brothers is concrete as is both my best friends and my parents.. do you know for a fact that his house is not a back or side split? (which commonly have concrete floors in the crawl space section..) clearly you dont know completely what you are talking about...

Second:
the tank is supported by the corners, so the joists have nothing to do with his problem...much like when building a stand, the horizontal members are for torsional support not for weight distribution..(ie you could build a tank stand that consisted of four posts tied together, both side to side and front to back..)he is OBVIOUSLY going to have to supprt the tank at the corners and regardless of the size the tank the joists will not be enough for this..IF the joists run the length of the tank then he will likely need a third beam in the centre of the tank aswell. LOL but like i said with a tank and set up this big...the joists are not a factor..he will most likely have a stand built for the tank and sump etc. that will distribute the loads evenly to the four corners(and possibly in the centre of the lengths)..therefore unless it is sitting on concrete which we know it isnt the joist sizing is pretty much irrelevent
he is talking about a 250 gallon tank...what are the max dimensions one of those tanks could have? have you ever seen a lintle beam over a door/ window break? i have personally driven my one tonne truck over a double laminated 2x10 beam with out breaking it...my truck weighs 2900KGs now a fishtank supported in four corners with evenly distributed weight would barely come even close to that kind of weight...not to mention the weight of a tank is static..

so sawman i would like you to dust off your iron ring and explain how the joists make any difference in a situation where beams are required..LOL cause if your counting on the joists to hold this tank, well...that is just funny..

the controling factors of this problem are the size and distibution of the tank(s) and all thier components..if a whole 10x10 (or whatever size) room is being used to house the stuff then it might be a good idea to support the whole floor with a larger beam (possibly steel) possibly two beams..and that would only be IF the joists are 2x6 or smaller...and that would be the only senario where the joist sizing matters..Supporting a whole room...

to reiterate:
Just supporting a tank..joist sizing/ spacing doesnt matter (you need to use posts and beams anyway, the joists simply stop them from swaying

Supporting whole floor... then, and only then the size of the joists matters for determining how many and how close to add new beams..And only a licensed engineer is going to be able to determine the exact minimum size required to safely support the setup..

i changed out of civil engineering to go into landscape architecture cause the math and numbers bored the crap out of me..LOL but that was after two years of taking architecture.

anyway this has gone on far long enough for me...JFRO, if your really concerned, which you should be with an investment this large you should consult a local engineering company in your town to get thier advice.
 
Guys, none of you seem to have it all right :)

There have been some fairly rude posts here (and all over RC)...

NanoReefWanabe with all due respect, you are very misinformed about the physics of floor loading and the very nature of floor construction. We can go into a lot of detail, but lets just make this basic. You claim to be a "civil engineer" of sorts, but you certainly have not shown a grasp of these concpets at hand. That would be fine, but you have been somewhat rude in the process of explaining what you think is going in.

Anway...
The joists, their spacing, size, span and direction all certainly do play a role. The joist size and spacing and span are used to determine the load that they can carry. The joists ARE NOT MERELY To keep the floor from "swaying". They are what gives the floor strength.

The sheathing over the floor and the blocking between the joists keep them from twisting and help to transfer some of the load to adjacent joists.

The direciton of the joists is VERY important when we are talking about a large dead load that will point load a portion of the floor. The subfloor only transmits PART of the load to the joists that are beyond the loads footprint. The further away the joist from the load, the less share of the weight it handles.

The closer the load to a load bearing beam or wall, the less deflection the load will cause.

The more joists the the load covers, the less deflection the load will cause.

This is VERY VERY basic physics and floor construction 101.

So lets take a 8' x 2' 250 gallon tank. That is about 2500 pounds of dead load. With joists 16" OC and the load perpinducular to the joists, it will cover 6 joists. That is around 400 pounds per joist. Some of the load will transfer to adjacent joists so you can figure about 300 pounds per joist under the tank and mabye 150-200 for the nearby joists. Now turn the tank parallel to the joists, and it is possible that it will only cover ONE joist, AT BEST TWO. That single joist will carry MOST of the load and be a disaster waiting to happen.

Secondly, a fish tank IS NOT supported by 4 corners. A tank that large will have a stand that makes contact in multiple areas and distributes the load over that area.

Sistered joists could easily support the load we are talking about in this thread. Placing the tank near a load bearing will and using a single properly sized H beam or paralam is certainly possible. We would need to know the size, spacing and span of the joists to size the beam properly.

Should you have finished you engineering degree, you would know that just tossing a load bearing beam anywhere in the span can cause unwanted effects in other areas of the span. It is wholey possible to transfer load from another bearing surface to your new support and cause a catastrophic failure. This is not likely but possible.

Just having an "engineering degree" or almost having one does not by ANY stretch of the imagination make you an expert (or even an informed laymen) when it comes to wood floor construction. I know guys that design rockets for a living and can't figure out how to use a framing sqaure to lay out a set of steps. I know civil engineers that have no idea how an internal combustion engine operates, and mechanical engineers that have no idea how strong concrete is. I know a guy that designs skyscrappers for a living, but knows nothing about wood floor construction... etc etc.

In other words citing a general degree as means of being an expert witness usually menas you are out on a limb and out of your area of expertise :)

Bean
 
Unfortunately, what you are not able to pay for is the insurance / lliability assignment in the event they make a mistake.

As someone above mentioned no one has all the answers, so, getting someone to cover your bases without going to an archt or struct eng will leave you some exposure if something happens.

Some of hte suggestions above are okay and possibly will work and help but to,make sure you dont lose your investment, I would reccomend going to a struct engr and spend the money neccessary

Bill
 
as someone with a PhD in civil engineering, i too, would consult a structural engineer. you might alos want to consult a geotechnical engineer based on the fact you most likely will need to understand the basic soil strength parameters at those locations. i see you are in NV, so most likely you will be supporting this on sands, and depending on where the natural groundwater table is, digging footings for your tank might not be as easy as digging a hole and filling it with cement. spend the few hundred bucks and get it engineered the proper way, its a small price to pay considering the thousands of equipment and livestock you will have invested.
 
never said i was a civil eng...

and i never said the joists stop the floor from swaying..i said they would stop the beams from swaying..

the reason i said the joists dont matter is beacuse you will have to reinforce the floor so much with beams anyway that the joists sizing etc...is irrelevent.. it would almost be easier to remove the joists where the tank is going, just like you would to add a stair case, just so you would have more head room to work with in a crawl space, rather then working below the 8 inch joists...please read my whole post before bashing me..

and like Sabo said you may also want to conect with a soils engineer..sand is very nice to work on, IF it is undisturbed..
 
I understand what you are getting at... and would agree to an extent. The reality of the matter is that the joists and their specs are going to be very important for this poject. It is possible that a simple sistering porject and a single support will be all that is needed. Thanks for the reasonable reply :)

The stair case analogy is not bad other than the fact that it would require the existing floor to be supported and the "tank" standing on a VERY TALL stand. If it was help "captive" by the surrounding floor it would not sway... but would take some though to do correctly. Still not a bad idea.
 
I agree with Bean myself, I myself am of the OVERKILL method. I have personally set up ALOT of buildings. Wood posts are great, BUT AND I SAID BUT!!!! Pressure treated posts!!! Makew sure they are DRIED!!! Pressure treated wood will SHRINK!! Ask anybody..as much as 1/4 inch. I buy a tractor trailer load a week I know. All of the wood sold in the USA is now ACQ or CAB treatment process and is supposedly safe for human contact. Also if you use pressure treated , use stainless fasteners, I have done my own corrosion tests, and this new ACQ eats regualr metal screws and nails so quick, hot dpped galvanized isn't looking to promising either. Concrete pillars would be great, but soil conditions are a whole differnet story up there. I won;t touch that with a 10 ft pole. Talk to someone who lays concrete foundations where you live, he could point you in the right direction.
 
Hey Bean, mark my words...in 10 years or sooner, we will see on the news where wood porches have pulled away from houses and collapsed. The ACQ pressure treating chemicals stop attacking the galvanized coating when the wood drys, but when the wood recieves rain, the chemical process continues and continues, my screws have had the threads eaten off within 8 months of being on my displays out in the rain, the kicker is the head of the screw looks just perfect, that is exposed to the sun and rain, but not in contact with the wood.
 
I appreciate all the feedback and I'll try to get back to you with more information this weekend. I also think I'll contact a Strutural Engineer, clearly this is much more complicated than I had thought it would be.

I'll get back to you soon. Thanks for the weel thought out discussions.
 
yeah I read a lot about that not long ago... just one more case of the enviro weenies and big lobbies forcing a sub par product into use. In the long run it will cause a greater env impact than the old arseneic treated stuff.

Soil conditions are pretty easy... the more clay , the larger the footing has to be. When you get to 100% clay, you need a footing nearly double the size of what you would need for good soil. Frost depth is a consideration due to heave... but not likely a problem under a house :)
Bean
 
can you guys use pressure treated wood inside your dwellings down there?

it is against the OBC (ontario Building Code) up here.

and i sorry i try to be reasonable, LOL but my fuse tends to be shorter then it should be...i do appreciate an informative reply/ critizism/ bashing, provivded there is good reasoning behind it...not just the "no, your an Idiot!" reply sometimes posted with out any reasoning/ proof/ or inteligent arguement as to why such comments are being made....

I have seen that; Bean you are a very tactful and informative person, and i appreciate that...as do many others i am sure
 
You would be surprised how many people DON'T reply in a kind manner and instead come unhinged :)

I think the new BOCA codes prohibit its use indoors. Have not really checked though. I do know that the new BOCA codes have been adopted in most areas.

Bean
 
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