chimney mortar Design Styles, Chimneys and Finish Discuss chimney mortar in the Pizza Oven Design and Installation forums; I am ready to begin building a brick chimney and I'm wondering what mortar to use. I'm especially concerned about ...

[briot]

I am ready to begin building a brick chimney and I'm wondering what mortar to use. I'm especially concerned about the heat as it draws up through the vent. I want to build a row or two with brick brick before I put on the duratach anchor plate. Does any one know how hot the air is (temp) as it travels through the vent? Any suggestions about what kind of mortar to use?

[RTflorida]

I have shot my flue area with my IR during a scary fire (flames actually going up the flue into the pipe. I have had sustained brick temps of around 600+ in that area.....I would stick with the refractory mortar.
another point I would like to make - I used regular mortar for all of my mosaic work which comes right up to my entry brick all around the entry. At this point my isulation is the thinnest of anywhere (2 1/2 of percrete). In the tile directly (within an inch) in contact with the entry bricks I have a reoccuring problem of the Type N mortar crubling/disolving/cracking. I've shot these entry bricks with the IR as well - 400+ degrees. SOOOOO, my advice is to stick with refractory mortar anywhere that you know will be subject to high heat unless that area is exposed to the elements. I've tried regrouting that small strip of tiles surrounding my entry with HeatStop, but because it does not handle the elements (rain) well, it turns to dust within a couple of months. I'm not sure what the answer is for an exposed area that must sustain high heat.
Anyone.....Anyone?????

RT

[dmun]

The vent area gets really hot. Build it with heat stop if you can get it.

[ThisOldGarageNJ]

I used Heat Stop 50 on my brick chimney, It will sometimes reach 250 degrees in the back area, I havent had any problems with it cracking or seperating inside or out. I also used fire brick for the chimney as well. My only misteak was making the chimney not wide enough, It works great, but not till you've been burning 15 or 20 minutes,,

Mark

[karl]

I would recommend to use a liner (heat resistent/fire brick material) in the chimney.
karl