How to add fireproofing to a B-rated inventory safe?

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I have purchased a b-rated inventory safe. It had a 1/2 in steel door and 1/4 in body. It has no fireproofing of any kind. I would like to add fireproofing on the outside and possibly on the inside as well. For the outside I am considering ceramic fiber insulation board and/or cement board, or possibly a two layers with cement board on top. I am not sure how to go about the door on the outside. For the inside I am considering making a bag with walls made of "panels". Each "panel" would be made of aerogel covered by nomex on both sides. The panels are sewn together using kevlar thread, with the front panel attached either by velcro or by zipper, thus easily removable.

Any suggestions and ideas other than "sell this safe and buy a fire rated safe" would be appreciated.
 
You'd better off building a fire rated closet that the safe sits in. Adding insulation inside won't protect it effectively.
This. Building a good closet shouldn't be too expensive. Make it big enough for a second safe.
 
This. Building a good closet shouldn't be too expensive. Make it big enough for a second safe.
I built a 3/4” ply cab around my safe and lined it with the “sheet” rock that goes above the furnace.
That was 15 years ago - no idea what that would cost today.
 
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I built a 3/4” ply cab around my safe and lined it with the “sheet” rock that goes above the furnace.
That was 15 years ago - no idea what that would cost today
Isn't that what the "fore proof" safes have?

I have seen a cut out of one, looked like just lined with some sort of sheet rock.

By the way, cutting all these safes is a joke, takes a full 5 minutes, maybe 7 minutes if it is your first time.
 
This. Building a good closet shouldn't be too expensive. Make it big enough for a second safe.

How thick Sheetrock for a good fire rated closet? Use “Green Board” for moisture resistance? Use “Cement Board” for durability? Multiple layers and/or combination of layers? Incorporate an exterior fire-rated steel door with hardened hinges and multiple deadbolts for security?

What are we talking about here…?
 
How thick Sheetrock for a good fire rated closet? Use “Green Board” for moisture resistance? Use “Cement Board” for durability? Multiple layers and/or combination of layers? Incorporate an exterior fire-rated steel door with hardened hinges and multiple deadbolts for security?

What are we talking about here…?
I dont know.

I would build it out of concrete blocks, and line them with sheetrock. Then I would build a plywood door and roof with sheetrock on it. That's it.

Basically, similar to the way I built a shed for a generator a few years back (except I didnt use sheetrock).

Since HD and Lowes sell different size concrete blocks, it can be built so you don't have to do any cutting, you can use basic tools.

I am sure there are detailed plans online.
 
You'd better off building a fire rated closet that the safe sits in. Adding insulation inside won't protect it effectively.
I was thinking about putting some mineral fiber insulation around the safe, rigidizing it and covering it with cement board on top. It's straightforward to do on the sides, and makes is sort of a fire-resistant closet on the outside. The only part I am not sure how I should handle is the doors. I guess I could just build a second set of doors on the outside. What Should I build them from? Wood is combustible and steel conducts heat. I am thinking some kind of steel "exoskeleton" on the outside and heat resistant mineral fiber insulation on the inside of the door.
 
I was thinking about putting some mineral fiber insulation around the safe, rigidizing it and covering it with cement board on top. It's straightforward to do on the sides, and makes is sort of a fire-resistant closet on the outside. The only part I am not sure how I should handle is the doors. I guess I could just build a second set of doors on the outside. What Should I build them from? Wood is combustible and steel conducts heat. I am thinking some kind of steel "exoskeleton" on the outside and heat resistant mineral fiber insulation on the inside of the door.
Don't forget about the back.
 
How thick Sheetrock for a good fire rated closet? Use “Green Board” for moisture resistance? Use “Cement Board” for durability? Multiple layers and/or combination of layers? Incorporate an exterior fire-rated steel door with hardened hinges and multiple deadbolts for security?

What are we talking about here…?
People over estimate the use of cement boards. There is alot of air in it and heat will penetrate quickly. 5/8 gypsum board is used over boilers and stuff.
I was recently in a restaurant that used 2 inches worth of sheetrock as a firewall.
 
People over estimate the use of cement boards. There is alot of air in it and heat will penetrate quickly. 5/8 gypsum board is used over boilers and stuff.
I was recently in a restaurant that used 2 inches worth of sheetrock as a firewall.
I am planning to use "SBI Microre-300 Mineral Fiber Board". The product is used for fireplaces and I think even refactories.
 
...with the front panel attached either by velcro...
this don't sound good, i would think the velcro would fail in a fire/extreme heat situation.

just rambling now...a few years ago, i had a conversation with a safe manufacturer rep and he told me if i really had something special to protect that i needed a fire proof safe, and that all fire proof safes are not equal and all you're buying is time until the contents gets "cooked", you need to spend serious money to give yourself the best chance of protection. maybe fire proof safe technology has come further since that conversation.
 
this don't sound good, i would think the velcro would fail in a fire/extreme heat situation.

just rambling now...a few years ago, i had a conversation with a safe manufacturer rep and he told me if i really had something special to protect that i needed a fire proof safe, and that all fire proof safes are not equal and all you're buying is time until the contents gets "cooked", you need to spend serious money to give yourself the best chance of protection. maybe fire proof safe technology has come further since that conversation.
I think you are right about velcro. I'll go with metal buttons sewn onto the Nomex with non-combustible Kevlar thread. and loops for them out of the non-combustible Nomex. Lenzip makes flame-resistant zippers, brass teeth on Nomex tape.

The fireproof safe technology was patented in 1860 by Silas Herring. Essentially, it's an outer layer of thick steel, inner layers of plaster and concrete and a thin inner layer of steel. There are still safes made this way by premium manufacturers like Fort Knox and American Security. They cost upwards of 5 grand. If rated by UL, these safes will have at least a TL-15 rating. The cheap gun safes that are abundantly available for a grand or two are technically not even considered safes by UL Laboratories. They are "Residential security containers". They consist of a fairly thin outer layer of steel, sheetrock and carpet inside. They are easy to open with basic hand tools and offer very little fire protection. To add insult to injury, sheetrock facilitates rust even under normal conditionts, it gets even worse when sheetrock is heated.

The safe ratings are, for practical purposes:
RSC - cheap "Residential Security Container" aka "Gun Safe" sold for 1-2 grand.
B-rated - inventory safes. Stores use them to keep expensive merchandise. Cell phone stores keep their inventory in them. Made out of mild steel plate, with no fireproofing. Stores rely on sprinkler systems and fire alarms.
TL-15 - minimum rating for a "real safe". These are often used by Jewelry stores to keep inventory. They can't get their inventory insured unless they keep it in a TL-15 safe.
TL-30 - better version of a "real safe". Often used by banks, government and various businesses.
 
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Cement board is less resistant to fire than gypsum. Magnesium Oxide plaster/board is what is used in high temperature locations that regular Firecode C or Type X gypsum wall board is considered insufficient.

You'd want a UL B label door & frame or access panel.

This is what I would do:
Set safe on concrete floor:
Create a box to contain the safe attached to the floor.
2 layers type X or Firecode C gypsum wall board over 1" of rigid mineral wool board screwed to 2x6 studs, fill between studs full depth with mineral wool batt, inside face cover with 1" rigid mineral wool board, same 2 layers of gypsum screwed to studs. Intumescent caulking all the wall board joints to the floor. UL B label door & frame, welded hollow metal, smoke seal/sweep + sill.
You are building a fire resistant "vault" for the safe to sit in.
 
Cement board is less resistant to fire than gypsum. Magnesium Oxide plaster/board is what is used in high temperature locations that regular Firecode C or Type X gypsum wall board is considered insufficient.

You'd want a UL B label door & frame or access panel.

This is what I would do:
Set safe on concrete floor:
Create a box to contain the safe attached to the floor.
2 layers type X or Firecode C gypsum wall board over 1" of rigid mineral wool board screwed to 2x6 studs, fill between studs full depth with mineral wool batt, inside face cover with 1" rigid mineral wool board, same 2 layers of gypsum screwed to studs. Intumescent caulking all the wall board joints to the floor. UL B label door & frame, welded hollow metal, smoke seal/sweep + sill.
You are building a fire resistant "vault" for the safe to sit in.
Magnesium oxide makes sense. The lining for steel making furnaces is often made from magnesium oxide.

I have seen inexpensive mineral wool board that was "not rated for direct contact with fire", whatever that means. The cheap kind is only rated for 400 degrees long term exposure, 500 short term. Wood burns t 451 degrees. Nor sure if it will work if I hide it from fire behind the Magnesium Oxide board?

I am wondering if I should use steel studs instead of wooden ones, in combination with something that addresses thermal bridging. I could also weld a metal box out of steel angle as an "exoskeleton" and put the insulation inside it, and the safe inside the insulation. Wooden box would ultimately be easier and cheaper to build, but I am leery of a wood framed structure for fire protection purposes.
 
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How thick Sheetrock for a good fire rated closet? Use “Green Board” for moisture resistance? Use “Cement Board” for durability? Multiple layers and/or combination of layers? Incorporate an exterior fire-rated steel door with hardened hinges and multiple deadbolts for security?

What are we talking about here…?
double 5/8 is 1.0 hour rated I think. Had to double sheet a kitchen in NYC for the fire code in a high rise.
 
Magnesium oxide makes sense. The lining for steel making furnaces is often made from magnesium oxide.

I have seen inexpensive mineral wool board that was "not rated for direct contact with fire", whatever that means. The cheap kind is only rated for 400 degrees long term exposure, 500 short term. Wood burns t 451 degrees. Nor sure if it will work if I hide it from fire behind the Magnesium Oxide board?

I am wondering if I should use steel studs instead of wooden ones, in combination with something that addresses thermal bridging. I could also weld a metal box out of steel angle as an "exoskeleton" and put the insulation inside it, and the safe inside the insulation. Wooden box would ultimately be easier and cheaper to build, but I am leery of a wood framed structure for fire protection purposes.
The 1" mineral wool board is to address the thermal bridging from the back side of the gypsum board through the studs. Fire retardant treated wood studs will be less of a thermal conductor than steel studs. The counter sunk fasteners for the gypsum board will be thermal bridges into whatever they are fastened too. You don't want metal to steel stud to metal to bridge through the envelope you are creating. Mineral wool board has to be covered with gypsum, it isn't supposed to be directly exposed to flame. The door will be the weakest point of the assembly.

Mind you after building a room like this, it may wind up costing the same as a rated safe.

double 5/8 is 1.0 hour rated I think. Had to double sheet a kitchen in NYC for the fire code in a high rise.
Has to be Type X or Firecode C. Just because it is 5/8" doesn't help you. Rated GWB has reinforcement fibers in it so it won't fail from thermal shock, combustion gas pressure, or hose steam impact.
 
I am thinking about gluing some Ceramic Fiber Insulation Baffle blanket onto the outer surfaces of the safe:

Amazon product ASIN B086WP64DXView: https://www.amazon.com/Ceramic-Fiber-Insulation-Baffle-Blanket/dp/B086WP64DX/

I can use Sodium Silicate (aka Water Glass, $20 per gallon) for an adhesive.

for $130 that's a roll of 24 lineal feet of material that's 25 inches wide. Plenty more than what I need.

Additionally use some colloidal silica rigidizer ($50 per gallon) once the blanket is glued onto the safe. That should convert it from soft blanket into a rigid insulation. Seems like a low-budget way out compared to even building a box. If it works for a kiln, it should work for fire protection, right?
 
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double 5/8 is 1.0 hour rated I think. Had to double sheet a kitchen in NYC for the fire code in a high rise.
2 Layers of 5/8ths sheetrock is a 2 hour fire rating. (Worked construction in hospitals)
Build closet out of 2x4 metal studs, 2 layers 5/8ths (BOTH sides of wall) stagger joints.
Use R11 or R13 unfaced rockwool insulation (will not burn), and seal up all wiring penetrations with fire caulking.
No air = No burn

Also want to get a "fire rated" door. They have a plate on the hing side of the door with a rating.

You can get "fire rated" wood studs but they are x3 to x4 times the price of regular KD.
 
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