Trouble finding high temp mortar mix "ingredients"

Hi there,

We have just finished our base and put the hearth slab on top! Now on to the Oven!

I am having trouble locating the correct parts for my high temp mortar. We are in Rochester, NY. Portland cement is easy to find but struggling to locate the remaining materials. Any idea on what types of stores we should be calling? Also, should we be using high temp mortar for the outside frame? or can we use regular old mortar for that part? The instructions are a bit un clear on this piece.

Thank you!

Hello, and welcome to the BrickWood forum.

We heard recently from another builder in Buffalo that they were having the same problem. I’m wondering if there is a local shortage of fireclay in upstate New York.

You would look for fireclay in ceramic supply outlets, and lime in garden supply stores or pool supply stores. The fireclay comes graded by “screen size,” and you want a relatively coarse screen—anywhere between 10 and 25. Screen grades get up into the hundreds, but those are for fine porcelain glazes, not mortar.

Ideally you should use high temp mortar for your outside frame. If you locate the other ingredients, you will have plenty to do that. Regular mortar is acceptable for the frame, but you have hot firebrick in contact with the standard brick, so there is a chance it will eventually deteriorate.

Hey. Im the guy from Buffalo! I could not reply to the last post as it said it had been deleted? Anyway thanks for your reply. You are the MVP of this forum and gave me the confidence to do this. So seriously thanks a ton it has been such a fun project so far. Been doing with my dad and loving it. Doing the herringbone now!

I found everything in the area. Clay even closer to you.
Fire Clay at Studio Sales Pottery Avon NY
Hydrated Lime ( You can find in Rochester I bet) I got at Buffalo Cement Accessories
Silica Sand Get at any pool supply store. Ask for filter sand.


Thanks Jack! I will give them a call tomorrow. This forum is great. Good luck with the oven floor!

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So glad you posted with an update and you were able to find everything. Don’t know what happened to your earlier post, but I do know you’ve made Mr. Haring a happy builder.

The herringbone was one of my favorite parts. Like laying a parquet floor or solving a puzzle. Really happy you and your Dad are enjoying this project.

I’m hoping @BrickWood will add the stores you mentioned to the materials finder. A big THANK YOU for persisting and tracking the materials down.

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