cheap excellent material for oven walls

[dpmphoto]

I've gotten alot of good info from all you guys so its time to return the favor.I found a new material to use for the inside walls of the oven its called hardi backer board, available at home depot.This material is a new answer to concrete board used to apply shower walls floors et.Its a tan material which comes in 5by3 foot sheets in quarter and half inch thickness.its good up to something like a 1000 degrees or more, it cuts easily and is not messy (crumbly like the concrete board).It also holds heaty very well and takes fireplace caulk fb13 very well.The best part is that its only 9 bucks a sheet much less than sheet metal.Oh yeh almost forgot its much lighter than concrete board and you can you use it on the outside as well instead of costly sheet metal. Cheers

[jrow]

dpmphoto,

Good info. I went to the site and read the Spec-Data http://www.jameshardie.com/pdf/specdata.pdf. I'm not sure of the temperature data you posted. Can someone with an engineering degree check this out and let us know?

John

[ublinkd]

Originally Posted by jrow

dpmphoto,

Good info. I went to the site and read the Spec-Data http://www.jameshardie.com/pdf/specdata.pdf. I'm not sure of the temperature data you posted. Can someone with an engineering degree check this out and let us know?

John

I looked at the spec data. The section that deals with heat testing points out that they used ASTM E136, which is the "Standard Test Method for behavior of Materials in a Vertical Tube Furnace at 750 deg C" (1382 deg F). There was no marked deformation to the material during this test. I have contacted the manufacturer to get their fully detailed test results. If I find out anything to the contrary of what I have presented I will post it up.

Art

[dpmphoto]

it seems to work fine in my oven however i'm not sure if any hazardous fumes are emitted(make sure you vent properly)

[ublinkd]

Originally Posted by dpmphoto

it seems to work fine in my oven however i'm not sure if any hazardous fumes are emitted(make sure you vent properly)

This is something else I am checking on. However venting is always a good idea!

[Crimson]

Hmmm this is very interesting this could cut down on the cost of building an oven big time. Do you have any pic's of your oven built with this board?

[ublinkd]

So today I contacted James Hardie Building products. I requested their detailed test reports, and the tech support person told me that the test reports cost money so I just asked my questions. I was told that all samples tested made it to the full 1382 deg F with no deformation (he also said it can withstand direct flame. He didn’t say for how long or how much flame but he did add that in). There was no scorching, flame spread, or noticeable smoke formation. I told him my plans for the material included a constant exposure to 500 deg F temps (I figured I would over shoot some). He said there would be no problem with this. He did warn me that the board is not meant to be used as an insulator and I would need to watch for the approximate 250 deg flash point of lumber 2x4’s. When I then mentioned I would be using metal studs he gave the thumbs up that everything should be good.

He did not know about any fumes that might be released and gave to common better safe than sorry answer on venting.

Ps. I would also like to see some pics of your oven you built.

[Crimson]

I am still waiting to see pic's of your oven you built with Hardie backerboard. Also did you use the 1/2" stuff or the 1/4"?

[Banditperformance]

I'm going to be using the 1/4" stuff in my oven. Just got done with the floor structure, will be posting more pics in my oven thread

[Crimson]

I just called Home Depot here in Canada and they do not sell Hardie but RONA does. They only have hte 1/2" stuff and it's $15.97 a sheet.