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I have a need to build a room that is resonably fire resistant. I have played around the thought of adding fire resistant panels underneath the dry wall, but if they heat up too much, they themselves with catch anything behind them on fire. The room is in the basement, so the floor is on the foundation but the ceiling and the three internal walls are shared with other rooms. The house is made or brick. I would go as far as to destroying the three walls and putting in concrete with re-bar, but the ceiling is my main concern.

I need a room to contain a device that is capable of internally heating itself to 3000 kelvin. I do not expect the room it get that hot, however, if the device malfunctioned it would get pretty hot, as the room is 20x20x12.AND the longest this room would be unchecked during the operation of the device is around 20 min.(this goes without saying that if the fire burned through the room, my home fire alarm would alert the fire dept.)

Can this be done, and if so, how? Clarification: I need this to be fire PROOF not super resistant, resistant is not enough. I know it can be done by turning my basement into a furnace, but I was hoping there was a slightly simpler solution.

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    Fire rating is usually measured in minutes. Do you have an idea of how long you want to contain a fire? Commented Feb 1, 2011 at 18:28
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    the 'fire rating' for storage cabinets and safes are based on the time that it'd take for paper to reach its flashpoint if in a 1700°F fire. Now, most fires aren't that hot (but in this case, we're talking about almost 5000°F ... those ratings are going to be useless)
    – Joe
    Commented Feb 1, 2011 at 19:00
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    What is this mysterious device? Commented Feb 1, 2011 at 19:14
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    I suspect that @allindal is the Human Torch's secret identity.
    – Doresoom
    Commented Feb 1, 2011 at 19:40
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    I would advise against putting such a device in such a vulnerable location. May as well stack dynamite next to the open fire. Commented Feb 10, 2011 at 1:48

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I might add that the primarily "fire rating" of wall and floor/ceiling assemblies is to allow occupants to safely exit the building, not to keep the building from burning down. The Type X gyp board affords some protection because the inherent moisture in the product can slow down the fire through your wall or ceiling. With these assemblies, you are basically looking at a way to escape the situation before your obvious portal to Hades has the structure tumbling upon you. Perhaps you should also look into a fire suppression system--not sure what the initial source of flame is (what might be burning other than building components), but sprinkler heads tied to a detector might be a good idea.

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  • Is there any better fire suppression system than water sprinklers?
    – allindal
    Commented Feb 9, 2011 at 1:45
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    @allindal - the suppression system really should depend on the likely source of the fire - in the rest of the house, a sprinkler is likely to be the best bet, but in the 'fireproof' room, you may want something else, depending on the heat source. The important thing is to NOT put in a suppression system that will only make things worse (for instance, if we're talking flammable liquids that float on water, then water sprinklers are a bad idea - they actually help the fire spread!). CO2, Halon, etc, etc, are all available, but pricier, and require more maintenance than water. Commented Apr 5, 2011 at 17:53
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I personally wouldn't recommend that you put this inside your house. If you really have something that gets that hot, I'd be looking into building a separate structure away from the main building. This was actually pretty typical in early America -- the kitchens of large homes were in an outbuilding, so should there be a fire, it only burned down the kitchen.

I'm no expert on fire resistance, but I'd look to instructions on how to build a brick barbeque. (normally, they're made from more than one layer of brick, with a special 'fire brick' on the inside). If you used two walls, and left a void in between, you could fill it with vermiculite or perlite, which are the typical filling for fire safes.

I would avoid steel in the construction, especially in the roof, as repeated heating would cause it to sag; I'd probably use wood, with the assumption that if there were a disaster, the roof could be replaced.

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  • It would severely handicap the usefulness if it was outside. There is fire brick on the floor, the problem is that the brick heats up rapidly.
    – allindal
    Commented Feb 5, 2011 at 2:03
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    @allindal : it might, but if you end up burning down your house, you have a good chance that your insurance company won't pay out; it's like anything -- is the benefit worth the risk?
    – Joe
    Commented Feb 5, 2011 at 2:08
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    The insurance policy has been adjusted, I had a guy come over.
    – allindal
    Commented Feb 5, 2011 at 2:15
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    @allindal ... oh, okay ... if you're really sure you want to do this ... you might want to see what full specifications of Firex boards are, as they claim : "The FIREX BOARD Suspended Ceiling System is the world's highest fire-rated system using a single layer of 6 mm FIREX BOARD, which achieved a fire rating of 5 hours integrity at 1200 °C in accordance with the BS 476: Part 22: 1987." ... and if it's mostly radiant heat, you might be able to put some sort of reflective layer on it.
    – Joe
    Commented Feb 5, 2011 at 2:26
  • this look promising, I'll look into it and will get back to you later
    – allindal
    Commented Feb 5, 2011 at 2:32
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1/2" drywall carries a 30 minute fire rating. This can be increased to 1 hour by upgrading to a fire-rated (Type X) 5/8" drywall. For a 2 hour wall, you can stack sheets one over another (stagger the seams).

In your situation, I would probably do metal studs (which provide higher fire rating than wood). Add a double layer of Type X drywall, along with a fire rated door. Be aware that any outlet boxes or other holes you put in the firewall will likely act as an exit point for fire, so try to minimize the number of holes you put in the wall (more info).

You will also want to think about a smoke detector for your setup. You have not stated what the object that is heating up is, but I suspect that there are some fumes or exhaust gasses which will escape from the object, and may trigger a false alarm. You will likely need to experiment with different smoke detector types to figure out what will work for your setup. You also need to make sure you are able to hear the alarm when it goes off (the fire door and fire rated drywall will be quite soundproof). They sell networked alarms or alarms with relay switches to trigger remote alarms if necessary.

Having said all of this, you may want to consider if it would be better to place this item in a small standalone shed away from your house. If you have the space for it, this would likely be a lot safer then having this item indoors.

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    for electrical outlets you might want to look at protecting them with Intumescent Putty Pads Commented Feb 2, 2011 at 12:34
  • How can 1/2 drywall have a 30 min heat rating against 3000 kelvin?
    – allindal
    Commented Feb 5, 2011 at 2:07
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    Well, the fire that reaches the drywall is not going to be 3000K. Whatever it is, the piece of equipment he is talking about will only generate that temperature internally (likely in a very small, tightly sealed cavity). A fire generated from that device will likely be much cooler, and should behave similar to any other household fire. Commented Feb 7, 2011 at 15:46
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It's hard to say anything useful without details...

I'd strongly recommend hiring an engineer to advise you on this. Preferably one who works on laboratory safety, since that's the closest thing I can think of to your scenario.

But as a non-expert reaction, which you should absolutely not trust:

Plaster has a higher fire rating than you might expect. There's water bound into its structure, and evaporation as it breaks down will delay the fire's progress a bit. Not much at these extremes... but one of the ways they make cheap dicument-protection containers (often called "fire safes", though they are generally not good security devices; "fire chest" is a better description) is to use a thick layer of a cement designed specifically for that purpose, and a good one is typically rated to keep its contents below 450 degrees F for an hour in a 1700-degree F environment.

So enclosing the room in multiple layers of suitable plaster/cement might help isolate it in case of an emergency.

Re fire suppression: Again I'd talk to an engineer. The non-water professional solutions (labs and industrial kitchens) involve filling the room with nonflammable gasses like Halon (tm?). These are not toxic, unlike CO2, but that won't stop them from smothering you, so there are serious safety issues here. Such systems require recertification on a periodic basis.

Which reminds me that you may need to look at active ventilation and heat extraction. And making those work with the fire protection.

This sounds like something you can't afford to do wrong, and may not be able to afford to do right. You may want to reconsider the project, or at least the approach, if you aren't able to make the needed investment in manhours, materials, and equipment

Then again, people do sometimes try to weld in their basements, which would present many of the same issues. If there is a small single point at high temperature, without much thermal mass, and with suitable safety precautions, it might not be as completely unreasonable as it seems. (But people also burn their houses down with much lower temperatures...)

But If you need to ask, you need expert advice, not a bunch of people in the Internet. Seriously. Engineer who knows this topic.

As far as fire PROOF goes: nothing will ever guarantee that unless it's constructed from the ground up with that as part of the design. See previous; I don't think your budget will handle it.

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I say that you should wrap the walls of your room in fire brick, like a fireplace, and then let the demon roar free. :)

This answer is partly for amusement, but also serious: do you want to slow down a fire, or actually make the room fire proof? How likely is it that things will get out of control?

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As this is not much hotter then the inside of some halogen light bulbs, it all depends on how much heat you are dealing with as well as the temperature.

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I don't think you're likely to be able to build something practically that will withstand those kinds of temperatures. Perhaps you'd be better off making a sealed area/room that is reasonably fire resistant and installing a sprinkler/inert gas fire supression system?

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