Please forgive me if this is an inappropriate forum to be posting this question. If so, maybe I could be pointed in the right direction.

I am building an indoor incinerator in the attic of my home. This has two purposes, which I’ll get into later. My question has to deal with the safety of the design. It’s basically an old upright refrigerated milk dispenser, the big stainless steel boxes typically seen on counter tops of school cafeterias. I have removed the pink insulation from the inside between the outer steel hull and the steel inside chamber. I plan on filling this space surrounding the inner chamber with cement sheeting called “Durock”, which is supposed to be fire retardant. This milk dispenser opens from the front with a large locking steel door, probably lined with the pink insulation on the inside, which I would also replace with Durock.

Of course a hole would be cut in the top for a flue, which would be tied into the chimney. The entire incinerator would sit on top a couple of concrete bricks, and be enclosed in a small “room” lined with one inch of Durock, ½ inch space separated by a steel spacers and then another sheet of Durock before being attached to the house (studs). I would plan on having about a foot or more worth of space between the incinerator and the “room” that surrounds it.

A burner from an old gas grill would be attached to the bottom of the chamber. A line would run from the burner, through a tight hole in the chamber, through all the concrete sheeting to a tank of L.P. located on the opposite side of an adjoining wall. The L.P. tank would need an electric valve, where the gas could be turned on at the flip of a switch. Also an auto igniter such as a spark plug. I haven’t quite figured that part out yet, but I assume it’s possible because there are valves that do just that in every thermostat driven residential gas furnace. Of course the tank could also be turned on manually, in case there is no electricity.

I would like to have an inline exhaust fan in the flue, but I’m afraid it would get a little warm and possibly be a hazard. So, knowing all of this is it relatively safe for the following uses?

Use #1
In case of an emergency where sensitive documents and hard drives needed to be destroyed instantly upon my command. A switch is flipped downstairs, the incinerator ignites itself and poof, national security is maintained! I figure a good burn for one hour would do the trick.

Use#2
In case of an emergency where there is a loss of power for an extended period of time, this could be fired up to keep my family warm. (Assuming we would all huddle around this thing and use it intermittently to keep from freezing solid.)

Check out a picture of a 3D representation of this plan at: http://eyecon.hypermart.net/incen.htm

Thank You

Novice Dave
delivertodavid@yahoo.com

[This message has been edited by NoviceDave (edited September 18, 2002).]

[This message has been edited by NoviceDave (edited September 18, 2002).]

There are several major flaws with this design that I know of. (Not necessarily the only ones):

1. Durock may be fire resistant but is not intended for use in this type of application. The nylon mesh that holds it together will melt and the Durock will crumble.
2. You have not mentioned air for combustion and what provisions you plan to make for that.
3. The design of the firebox will transmit way too much heat through the walls to make it safe in a restricted space you are talking about. The firebox would have to be made of multiple layers of metal or other noncombustible material with a ventilated airspace between the layers to reduce the heat transmitted through the wall.
4. L.P. gas containers should never be stored (much less used) inside a building. This will be a violation of the fire code.
5. Without a UL label or at least an engineers seal and approval from the fire marshal you will also be in violation of the fire code.

All and all I would tell you NOT TO PROCEED WITH THIS PLAN. It has way too many flaws and will be extremely dangerous. If you must have an incinerator consult the professionals or at least use a “zero clearance” fireplace and have your plan approved by the fire marshal before you start!

Glenn

Thanks for the reply. That is a very good point that you made about the fabric melting within the concrete material. Also, the point about more space being needed around the incinerator is well taken.

And yes, I had forced air in mind, however failed to mention that or reflect in the picture (see link).

I guess you’re right, that was a pretty dumb ideal. Thanks.