Fire protection for a safe?

[Dan_Johansson]

I have a safe that is some form of homemade contraption based on a "money box" from an ATM. It's basically a thick metal shell with a sturdy door, approximately 500 mm wide, 350 mm high, and 600 mm deep. It stands directly on a concrete floor in a storage room that I plan to convert into a hobby room in the coming years. The room is connected to the garage and the house.

The question is how best to protect the safe against fire, which I believe is a greater risk than someone breaking in and stealing a few papers and a hard drive with mixed pictures.

I have been considering steel studs and gypsum, but should I build "two boxes" with insulation in between? Thicker layers of gypsum? How long can one reasonably delay the heat of a fire from warming up the contents to "destructive" levels?

All thoughts on the subject are gratefully received!

 

[Asbesträdd]

Stone wool maybe? It's a good insulator and it can't burn or melt, but I don't know what happens if it burns around it.

 

[Alfredo]

Stone wool maybe?

Sounds sensible! Otherwise, asbestos would probably work well, but I guess it doesn't seem appropriate. From the Wikipedia link "Asbestos has been used as fire protection in, among other things, steel constructions".

 

[Dan_Johansson]

Rock wool perhaps? It's a good insulator and it can't burn or melt, but I don't know what happens if it burns around it.

I know roughly what happens, the "wool" itself isn't affected, but the binder is... It loses its properties already at 200 degrees... as long as you don't touch the insulation it looks the same, but if you poke it, it just crumbles... it might work as insulation between two layers of "something else"....

 

[Dan_Johansson]

Sounds reasonable! Otherwise, asbest would probably work well, but I guess it doesn't seem appropriate. From the Wikipedia link "Asbest has been used as fire protection in, among other things, steel constructions".

I think I'll stick to things that are both harmless and readily available in building supplies ...

Is it better to build a "heat-resistant" construction perhaps? Cast it in half a meter of unreinforced concrete?

 

[Asbesträdd]

I know roughly what happens, the actual "wool" is not affected, but the binder is. It loses its properties already at 200 degrees.. as long as you don't touch the insulation it looks the same, but if you poke it, it just falls apart... it would probably work as insulation between two layers of "something else"....

Oh... Now I know something new! There is something called ceramic wool which is both fireproof and holds itself together. After a layer of ceramic wool, you can have drywall.

 

[Dan_Johansson]

Well... Now I know something new! There is something called ceramic wool that is both fireproof and self-supporting. After a layer of ceramic wool, you can have plasterboard.

That's a pretty good idea... (that I didn't think of it myself, I have ceramic felt in my wood oven...)

The only problem is the price of about 1000 SEK/sqm for 50 mm thick felt...

 

[useless]

Stone wool steel studs and plasterboard should work well. On Paroc's website, there is some information on how to build fire-rated walls depending on the requirements you want to achieve.

 

[Dan_Johansson]

Popnita together maybe?

 

[useless]

There is also mineral wool that is fire resistant, but maybe it's overkill if it's inside a wall? https://www.paroc.se/produkter/bygg...g-for-byggapplikationer/paroc-fps-17-firesafe

 

[Dan_Johansson]

There is also stone wool which is fire-resistant, but it might be overkill if it's inside a wall?
[link]

I also think that if it does catch fire, the insulation works well as long as it's between two plasterboards .. after it has burned, it doesn't matter if the insulation collapses when you lightly touch the "box" ....

 

[topmount]

Thinking that it is probably just as important to protect it against water. Both in case of a possible unintended activation or flooding.

 

[Asbesträdd]

It could be Metal Gypsum Stone wool (Gypsum again?).

 

[Keld]

And then a sprinkler over the whole konkarongen.