Yet another heavy safe thread

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Flintshooter

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Has anybody ever had a one to two ton safe installed on anything but a concrete slab? Just at the daydreaming stage at this point but wondering if any wood floor is capable of it.
Looking at the Brown 7256, and at the lightest a TL-15 is 4880 pounds.
Where I would like to put it is a small twenty year old addition on an older house.
I am taking for granted that the floor has to come up for reinforcement of both joists and the floor itself. Worse case would be fill in with pea gravel and pour concrete.
 
I am not a structural engineer, but would start by finding out if the addition was done by a licensed contractor, inspected, and found in compliance with building codes. If so, your issue may not be with overall weight so much as distribution of that weight in the process of moving it in and locating.

Browning should have some information on suitable underpinning or shoring up to assure safety. A professional engineer or experienced contractor would probably test for deflection under smaller loads to get an idea of load bearing capacity.
 
To the two replies so far.
I was around when the job was done, and each step had to be checked off by the local inspector. I don’t think for one second that what is there NOW will support that kind of weight. That’s why I mentioned taking up the floor and reinforcing. Adding to the joists there now, possible adding some more joists where there aren’t any now, and changing the floor from MDF and carpet to two inch planking and hardwood flooring.
 
Depends upon the where & how.

For one, how the safe loads matters. A 3x4 foot safe is sitting on 12 square feet, or 1728 square inches, 4800# would then only bear down 2.7#/sf. But, if the thing has "feet" of any kind, those will concentrate the load.

Just because you see concrete does not mean it's good concrete.
Lots of basement floors out there that are only 3" thick, and only 1800-2000psi concrete and without reinforcing of any kind. But, wait, I just ciphered that the load might only be 3#/sf--but, that's in compression. If the slab is thin, it's like putting a weight on a thin blanket, it wants to sink, and that sinking puts the slab in tension.

Now, wood construction can be similar. Wood is an outstanding building material, but you need to design it to the loading needed. So, a floor designed to a live load of 40psf is going to groan a lot with 400psf of safe upon it.
 
Choice two in my case would be the garage the room I would like to put the safe in is attached to. The house was built 1957/58 and the floor of the garage was once the floor of a carport. The addition and garage were built in 1998. After all those years of Indiana seasonal temperature changes there was not a hint of a crack in the floor of the carport so I’m guessing it was poured thick and reinforced. Because I wasn’t thinking about putting a safe in the new room twenty years ago (or even living in the house for that matter) I didn’t pay a lot of attention to what’s under the floor. It’s only about 18 inches higher than the garage slab, so just taking up the wood floor and pouring concrete in part of the room might be the best solution.
 
CapnMac has the right idea. You need to compare the load rating of the floor in a unit like psi or psf to both the weight and area of the safe.
 
It would depend and might need some subfloor reinforcement if not on a slab. Call a company that specializes in subfloor reinforcements and repairs
 
Depends upon the where & how.

For one, how the safe loads matters. A 3x4 foot safe is sitting on 12 square feet, or 1728 square inches, 4800# would then only bear down 2.7#/sf. But, if the thing has "feet" of any kind, those will concentrate the load.
Looking at Brown’s website again, the TL-15 7256 has a footprint of 62”x36” for a total of 2,232 sq. inches. Divided by 144 that comes out to 15.5 sq feet. 4880lbs divided by 15.5 sq feet comes out to a shade over 330 lbs per square foot. Admittedly, math has never been my strong point but your 2.7 lbs per sq. ft sounds way too low.
What I’m really asking is if anybody has been able to install a super heavy TRUE safe on anything but a concrete slab.
 
but your 2.7 lbs per sq. ft sounds way too low.
Yep, looks like I dropped a decimal.
Which is why, as an architect, I haire PE to do math to make ure my hair-brained ideals are actually buildable, and not just rule-of-thumb suppositions.

Which happens a lot in renovations, wherer it's far too easy to suppose more is available than i really there, which mean you need to core stuff and get a PE involved.
 
Something I haven’t made clear and should have is that the addition I am wanting to use is not very high above either the outside ground level or garage floor. A quick something less than precise measurement a little bit ago showed sixteen inches above the garage floor. Since there is no crawl space, any beefing up will require removing the existing floor. Since nobody has chimed in saying that they have installed a safe of a ton or more on a non-concrete floor I’ll just put the subject on the back burner until it is time to actually do something. A two or three inch hole in the header in the garage along with a flashlight should tell me what I’m dealing with. It isn’t a huge issue having the safe in the garage, I’d just rather have it in the addition. Engineers will be consulted when the time comes.
 
Remove the floor

Post hole dig 12” piers flared at the bottom at four corners of safe

Fill with concrete with post bases at the top

Run two 4”x8” or 10” wide beams perpendicular to the direction of the floor joists that sit on the post bases up tight to the bottom of the floor joists that are carrying the weight and add blocking between each joist above the beam to prevent rolling.




Or call a professional, as I am not responsible if your safe falls through the floor and you have to rent a crane to get it out.
 
What I’m really asking is if anybody has been able to install a super heavy TRUE safe on anything but a concrete slab.
I'm a Civil PE, but I don't play one on TV. We build skyscrapers every year, with vaults tens of stories in the air. . . ability is not the question, competence and expense are.

Get a homebuilder you trust, not your brother-in-law, to design a solution. Any homebuilder worth his fee can do the design.
 
Guys, right at the moment this is a dead issue.
ALL I was asking is if anybody had ever placed a ton+ safe on a floor that wasn’t solid concrete. Not asking how to do it, just if anybody ever had.
One thought has occurred to me today.
Here in the midwest there used to be a fairly common structure known as a bank barn. They were timber frame construction, usually built on a slope. The slope allowed for an easily accessibile bottom story for sheltering livestock and everything above was used for hay, feed, and implement storage. The framing was stouter than anything you will normally find in residential construction but I don’t recall ever seeing any joists between the timbers that were even close to 16 inch centers. The boards used for both the main floor and mow were two inch thick planks. And I know from personal experience gained from many a sweaty and sweltering afternoon, those planks supported many tons of hay bales. At least 180,000 pounds in one I can remember in particular.
As for my project, I will probably just sacrifice the garage and forget about beefing up the room addition.
 
The boards used for both the main floor and mow were two inch thick planks. And I know from personal experience gained from many a sweaty and sweltering afternoon, those planks supported many tons of hay bales. At least 180,000 pounds in one I can remember in particular.
I am a PE and CapnMac has the right idea, even if he dropped a decimal. The answer is that standard residential wood floor construction will not withstand the load you are proposing. It won't even come close. It will collapse.

Even a standard concrete floor won't suffice. Properly designed, a reinforced concrete floor will though.

You need the services of a PE or an architect to design a proper floor for that safe.
 
I am a PE and CapnMac has the right idea, even if he dropped a decimal. The answer is that standard residential wood floor construction will not withstand the load you are proposing. It won't even come close. It will collapse.

Even a standard concrete floor won't suffice. Properly designed, a reinforced concrete floor will though.

You need the services of a PE or an architect to design a proper floor for that safe.
I stated in my second post in this thread that I was well aware the current floor would not support the weight. Having been around both residential and commercial construction for most of my working life to see how things are built I am also aware that no standard floor residential or otherwise will support the weight.
My story about the tons of hay not breaking down barns (something not unheard of btw) was a statement of wonder, not a dispute that a normal residential floor couldn’t support over two tons in a 15.5 square foot area.
I have a long time to get all my ducks in a row on this so I will have time to check ahead of time but I do question that it will take some kind of special concrete floor. A friend has the equivalent of several large safes sitting on a standard garage floor in the form of milling machines, a HUGE lathe, surface grinders, etc. The milling machines are only around a ton but that ton is spread over a smaller footprint. It’s been like that for years.
 
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