Fireplace Mortar

[bcwsport]

I was wondering what type of concrete/mortar would be recommended for and outdoor fireplace. Do you set your fire-brick using specialized "fire certified" concrete or do you feel that this step is even necessary?
Thoughts?

[cgland]

Definitely use a fire rated mortar or you could get popping and crumbling

[GreenMonster]

yes, it's necessary. typically called refractory mortar. Heat stop is a popular brand. keep your fire brick nice and damp or they'll suck the moisture out of the mortar. most guys keep them soaking in water.

[paponte]

What he said ^. You must use high temp mortar on your brick, but it is not necessary on the block or cultured stone.

[CaptainsLS]

I use heat-stop like Mark mentioned. Make sure you test that stuff out a bit to get used to it ( you will understand once you get some on a trowel :) ). Also dont forget to design the box using joints that are about 1/16" with the heat-stop.

[danf]

Yes, mix small batches first until you get used to it- it sets up much faster than regular mortar!

[WoodwardsChris]

Firerock/Emberlok will not guarantee their fireplace kit if you do not use their fireproof mortar.

[Ground effects NH]

I use heat-stop like Mark mentioned. Make sure you test that stuff out a bit to get used to it ( you will understand once you get some on a trowel :) ). Also dont forget to design the box using joints that are about 1/16" with the heat-stop.

A very good point:gossip: