Bolting Down Safe

[Boltz]

You can drill into post tension, I've drilled thousands of holes into post tension concrete slabs. The cables are blocked up and set in the center of the slab if it's done right. You can drill 1" in the slab top or bottom, use a Hilti drop in anchor and make sure the square imprint from the set tool is clear when set. The 3/8" are good for over 2000lbs, I've hung 800lb+ exhaust fans using drop in anchors in post tension concrete slabs.

Glad it's worked out for you - I would be too paranoid to even think about drilling into one of those babies

[mstlaurent]

Glad it's worked out for you - I would be too paranoid to even think about drilling into one of those babies

Me too, my house in AZ has a post-tensioned slab, I ain't touching it.

Unfortunately I have a fire safe, so I can't drill holes in the sides. I'm thinking about rigging up some L-brackets that I can bolt to the wall, then plop the safe down over them and bolt them through the holes in the bottom of the safe.

[jak77]

Havent gotten around to checking if its post tensioned yet. I hope its not!

[kermitz]

I'm very reluctant to drill into my post tension slab. My safe alone weighs 575 lbs, and it took my father and I almost an hour to move it with an appliance dolly. Now it's filled with a couple hundred pounds of guns and ammo. I also have two indoor dogs and a wireless home security system. I have several nosey neighbors and either my wife or I are home 90% of the time. If anyone breaks in and makes off with my safe or it's contents, they earned it.

[SJgunguy24]

Glad it's worked out for you - I would be too paranoid to even think about drilling into one of those babies

That's how we hang equipment and the HVAC system. Everything is tested and certified by UL. Just think about all that stuff above the ceiling when you walk into a building, and how it stays up there.

Me too, my house in AZ has a post-tensioned slab, I ain't touching it.

Unfortunately I have a fire safe, so I can't drill holes in the sides. I'm thinking about rigging up some L-brackets that I can bolt to the wall, then plop the safe down over them and bolt them through the holes in the bottom of the safe.

I drilled 2 holes in my fire safe, I also sealed the holes with fire caulk and replaced the sheetrock that I removed to make room for the lag bolts. Those plugs were caulked also.
If you understand how everything is built and how it works you can solve a myriad of "problems" that arise. You really want those safes secure, not for burglars but for seismic reasons. You think that was heavy before, now image that laying on the floor door side down and all of your s**t is inside.

[mstlaurent]

I drilled 2 holes in my fire safe, I also sealed the holes with fire caulk and replaced the sheetrock that I removed to make room for the lag bolts. Those plugs were caulked also.
If you understand how everything is built and how it works you can solve a myriad of "problems" that arise. You really want those safes secure, not for burglars but for seismic reasons. You think that was heavy before, now image that laying on the floor door side down and all of your s**t is inside.

Well, the good news is that the safe is in Arizona, so earthquakes are no longer a problem. However, I do still want it bolted down to prevent burglary. Thanks for the suggestions.

[sandman21]

That's how we hang equipment and the HVAC system. Everything is tested and certified by UL. Just think about all that stuff above the ceiling when you walk into a building, and how it stays up there.

UL rating is meaningless for anything hung in a building in CA, just FYI, ICC-ES approval or an equivalent, LARR or IAPMO, UL is not, there are ways around the requirements however they are not easy.

If you understand how everything is built and how it works you can solve a myriad of "problems" that arise. You really want those safes secure, not for burglars but for seismic reasons. You think that was heavy before, now image that laying on the floor door side down and all of your s**t is inside.

The safe will be fine not bolted down in a seismic event, it would be a precentage of the weight

Not an engineer, but from what I have seen and read, post tensioned slabs are used where the soils are difficult and subject to a lot of expansion and contraction from wet to dry. If you build a house on expansive soils (much of So Calif) you can get a lot of differential movement, which causes cracks and settlement. The end result is very unhappy homeowners.

Post tensioning is also used in overpasses, where there is a long span between piers.

In residential construction soils is the reason for the post tension slabs. Post and pre tensioning are used everywhere, parking garages, some school, commercial, office, and bridge.

From what I have noticed is post tension slabs tend to be thinner, and lighter. Saves money on the mix and rebar since less is used for post tension slabs. Also I have never seen any post tension for commercial construction, only residential and this includes high rise apartment buildings. All commercial buildings I see have corrugated pan deck with rebar laid on iron beams or truss systems.

Lots of large warehouses are starting to post tension slab on grade, forklifts are royal *****es on slabs.

You can drill into post tension, I've drilled thousands of holes into post tension concrete slabs. The cables are blocked up and set in the center of the slab if it's done right. You can drill 1" in the slab top or bottom, use a Hilti drop in anchor and make sure the square imprint from the set tool is clear when set. The 3/8" are good for over 2000lbs, I've hung 800lb+ exhaust fans using drop in anchors in post tension concrete slabs.

A 3/8” Hilti HDI is good for 870# in 2000psi conc. and 1115 in 4000psi, just be aware that not all jobs will accept HDI’s or similar, I personally don’t allow them, it a good thing to find out beforehand.

What are post tensioned slabs good for, in the context of a garage floor? I mean, I know they have more tensile strength, but is that any kind of advantage for this application over ordinary rebar concrete?

Concrete has almost no tension capacity, the reason for adding rebar, cracks are caused when the tension capacity of concrete is exceeded. Post tension slabs force all or most of the slab into compression.

If people need to bolt to post tensioned slabs, locate the tension strands, even if you are not going to drill deep enough to hit a strand that is in the correct position, there are anchorage and the ends of the strands, so be aware.

[Fate]

Red Head Hammer-Set. Heavy Duty Nail Drive Anchors 6-8 of these and your safe isn't going anywhere, unless you've got it attached to a tow truck

Those are made out of ZINC! Shear strength is about 300 lbs. Pretty easy to generate that kind of force. Which is good because otherwise you will have permanently installed your safe, never to be moved.

My safe is held down by 3/8" x 4" Rawl "5 piece" bolts. We use these for rock climbing protection anchors and are good for holding 5000 lb worth of force. I can also take them back out if I wish to relocate the safe. This isn't possible with those hammer-in studs some people use.

http://7summitsoutfitters.com/climbing/climbing-hardware/bolts-and-hangers/rawl-411302.html

[sandman21]

No, don't rely on that. Depending on where your house is (with respect to the nearest fault), a quake could easily have enough horizontal acceleration to overturn a safe. For example: our house is rated for 1g vertical and 0.65g horizontal. For a gun safe that is 6' tall and 27" deep, if the overturn moment front/back exceeds 0.375g, the safe will fall over (assuming it doesn't slide, and on rough floors, it's unlike to slide). So if we get unlucky and the next earthquake is aligned with the front/back direction of the safe, and I happen to be standing right in front of the safe, then I'll look like a pancake, with 1300 lbs of Sturdy Safe on top of me. The Brady people would probably score that as yet another death caused by guns ...

For that reason, I'm uncomfortable relying purely on the hold-down bolts in the bottom of the safe. If you look at the lever arm (safe is 72" tall, 27" deep, weighs 1300 lbs, the bolts are spaced about 20 inches, there are only 3 hold-down bolts in the bottom, and a 0.65g earthquake is directed so all the load ends up on a single bolt), then the total force on the one unlucky anchor bolt can be as high as 1500 lbs. While a 1/2" redhead anchor in a 2500# slab should theoretically handle that, there is darn little safety margin. With 1/2" lag bolts into floor joists, there is no way to hold the safe down in an earthquake. That's why I also secure the safe at the top; the lever arm there is much better (72" of lever arm rather than 20"), so a small number of concrete anchors or lag bolts can be very effective.

Never said to rely on it, only dealt with the claim that seismic is more of an issue than someone trying to rip it out of the ground.

You house is not rated for 1g vert. and .65g horiz., you might be referring to Sms/Sm1 or Sds/Sd1. Those numbers are then used in equations to determine the loading on the house. The same applies to anything that attaches to the ground or the house; for the most part it is based on Sds. If you tell me the general location I can tell you what the load on the safe will be allow if the loading and capacity on the anchor bolts.

If we assume your numbers 72”x27”x20” with a weight of 1300lbs, the load per anchor using a .65g, all the safes I have seen have 4 anchors one in each corner so we will assume that, gives us a load of 761# per bolt this is without accounting for the resisting moment caused by the weight of the safe and its contents.

I would put as many anchors as I can.

[FXR]

These are a little harder to remove than the rawl bolts - you'll have to beat them in deeper or cut them with a sawzall if you didn't drill the hole deep enough. They have the advantage that they can be had in longer / larger diameter sizes then normal rawl bolts. (they do make huge rawls, but they aren't sold everywhere.) 4 or these, with the biggest washers you can find, plus a 1/2" lag screw at the top into the wall studs behind/next to the safe, and moving the safe will not be an issue.

I just looked at the Costco safe offerings - how is this $3500?!

http://www.costco.com/Browse/Product.aspx?Prodid=11642770&search=gun+safe&Sp=S&cm_re=1_en-_-Top_Left_Nav-_-Top_search&lang=en-US&Nr=P_CatalogName:BC&N=5000043&whse=BC&Dx=mode+matchallpartial&Ntk=Text_Search&Dr=P_CatalogName:BC&Ne=4000000&D=gun+safe&Ntt=gun+safe&Mo=7&No=7&Ntx=mode+matchallpartial&s=1&topnav=&Nty=1&s=1

[jak77]

Those are made out of ZINC! Shear strength is about 300 lbs. Pretty easy to generate that kind of force. Which is good because otherwise you will have permanently installed your safe, never to be moved.

My safe is held down by 3/8" x 4" Rawl "5 piece" bolts. We use these for rock climbing protection anchors and are good for holding 5000 lb worth of force. I can also take them back out if I wish to relocate the safe. This isn't possible with those hammer-in studs some people use.

Good points. I dont think Ill use the hammer-in studs just in case I need to move it in the future.

I just looked at the Costco safe offerings - how is this $3500?!
http://www.costco.com/Browse/Product...nav=&Nty=1&s=1

Im sure none of that 3500 went to true protection, more for display purposes. I would never pay that much for something like that, Id rather put that money into real protection. I wish I had that much right now for a safe.

[SJgunguy24]

UL rating is meaningless for anything hung in a building in CA, just FYI, ICC-ES approval or an equivalent, LARR or IAPMO, UL is not, there are ways around the requirements however they are not easy.

The safe will be fine not bolted down in a seismic event, it would be a precentage of the weight

In residential construction soils is the reason for the post tension slabs. Post and pre tensioning are used everywhere, parking garages, some school, commercial, office, and bridge.

Lots of large warehouses are starting to post tension slab on grade, forklifts are royal *****es on slabs.
A 3/8” Hilti HDI is good for 870# in 2000psi conc. and 1115 in 4000psi, just be aware that not all jobs will accept HDI’s or similar, I personally don’t allow them, it a good thing to find out beforehand.
Concrete has almost no tension capacity, the reason for adding rebar, cracks are caused when the tension capacity of concrete is exceeded. Post tension slabs force all or most of the slab into compression.

If people need to bolt to post tensioned slabs, locate the tension strands, even if you are not going to drill deep enough to hit a strand that is in the correct position, there are anchorage and the ends of the strands, so be aware.

I've done a ton of OSHPOD jobs and labs when I was still working in the trade (sheet metal worker/mechanical). I was usually a layout guy and fireman (problem solver) so finding different ways within the project specs was one of my specialty's. I used to have a large part of the I.S.A.T. cataloge memorized. But unlike my boss, I had to do all the work too. No trailer time for me.

These are a little harder to remove than the rawl bolts - you'll have to beat them in deeper or cut them with a sawzall if you didn't drill the hole deep enough. They have the advantage that they can be had in longer / larger diameter sizes then normal rawl bolts. (they do make huge rawls, but they aren't sold everywhere.) 4 or these, with the biggest washers you can find, plus a 1/2" lag screw at the top into the wall studs behind/next to the safe, and moving the safe will not be an issue.

Wedge anchors, these work great if you can get them set and hit em square. If not they can spin when you torque them down. Epoxy and studs is also an option, but the holes need to be clean, no dust at all so the epoxy can take a hold.

[sandman21]

I've done a ton of OSHPOD jobs and labs when I was still working in the trade (sheet metal worker/mechanical). I was usually a layout guy and fireman (problem solver) so finding different ways within the project specs was one of my specialty's. I used to have a large part of the I.S.A.T. cataloge memorized. But unlike my boss, I had to do all the work too. No trailer time for me.

Just a warning, OSHPOD standards are not accepted outside of OSHPOD, several MEP contractors have learned that the hard way, they did not like the testing requirements for blue bangers. So doing things the way it has always been done can get you in trouble.

[Rocket Man]

I worked on a big name hotel remodel- (on a small section of the hotel) & the electrician had to x-ray the tensioned slab for core drilling 1-1/2" holes for conduit through 11 floors!! Even with the x-ray pics he still hit one, I was 75' away & I felt the floor rumble as it made a whipping sound under my feet & I herd a loud bang when it slammed against the parking structure built right up against it!

The hotel patrons had no clue at all.........

[jak77]

I worked on a big name hotel remodel- (on a small section of the hotel) & the electrician had to x-ray the tensioned slab for core drilling 1-1/2" holes for conduit through 11 floors!! Even with the x-ray pics he still hit one, I was 75' away & I felt the floor rumble as it made a whipping sound under my feet & I herd a loud bang when it slammed against the parking structure built right up against it!

The hotel patrons had no clue at all.........

Was the electrician okay?