Keva or Beehive style

[Tem670]

Trying to build my first beehive style patio fireplace and can find almost no info on how to do it. Let me lay out my idea and hopfully somone can give me some advice. Last summer I built a 3-4 foot concrete block patio wall. All cores filled with cement. Wanting to build a corner fireplace. Have one layer of concrete blocks for a base. I cut and bent tomato plant cages for a frame then covered it with chicken wire. I ordered some cerimac blanket for the back side and bottom under the fire brick. Don't want to spend the money for firebrick for the whole inside.

That's where I'm at now and where I'm stuck. I don't know what materiel or process to do now.
my idea is to cut up paper leaf bags and make a paper machie schell. Them cover the outside with ??? Refractory cement or stucco or?? Then when dry burn off the paper and coat the inside with the wire with???? Any ideas? Totally stupid plan?? HELP!!! lol

[Tem670]

Lol. New idea. Instead of using then burning out paper I'm thinking of using wet cerimic blanket with a some kind of coating on inside and out . But what? Stucco or refractory cement or ferro cement?

[SableSprings]

Welcome Tem670 !

How big an opening are you shooting for? Be aware that ceramic batting has no compression strength...meaning it will compress under the weight of the firebrick floor. In addition, this compression will be most likely be very uneven so your firebrick "floor" will not be level or stable. We use ceramic batting as the insulation on the outside of the masonry oven with a ceramic board underneath (which has significant compression strength) to support the oven's weight. It would appear to me that you are using the ceramic batting to simply keep the outside cooler...not to retain heat (as done in the masonry oven) to cook/bake.

You mention Kiva and Beehive styles, so I'm assuming you want a smoothly curved shape culminating at a narrow(er) chimney opening. These styles would most commonly be formed using clay or a refractory casting material. In my opinion, you would have the best luck actually casting the fireplace with 2"-3" thick refractory that you mixed yourself ($). David S on this site has used wet paper over a sand form for casting ovens & kilns. This might be something to consider. The formula for our homebrew refractory mortar is 3:1:1:1 (sand, builders lime, fire clay, and Portland cement) and it's been used successfully for casting ovens by some members of this forum. You would have to create an inner form and then either start building up the walls using an outer form to contain the refractory material or go in smaller ring steps (letting each ring set up before applying the next layer on top). Casting an also be done by sections which are assembled after hardening.

After your fireplace is completely cast, you would apply the ceramic batting, hold it in place with something like chicken wire, and then apply a couple outer coatings of stucco. Even though you are not thinking of cooking with your fireplace, you'd still want to do slow curing fires to reduce the amount of cracking in the refractory. David S recommends addition of stainless steel needles in the refractory to reduce cracking, but it sounds like you are looking to do this at the lowest cost possible...so you'll probably skip this addition. The ceramic batting will absorb moisture, so covering the fireplace during extremely wet weather or incorporating a waterproof additive to the outer stucco coat would be advised.

It also would be helpful for us to know your general location...Oregon, Arizona, Norway, Australia's Gold Coast, etc.

[Tem670]

First, thank you for sharing your time and knowledge. I am located in Southeast Nebraska. I will heed your advice about using ceramic board under instead of the blanket. I already have the wire and chicken wire form made but need to tweak it a bit. So can I just use the blanket around the outside with stucco over it and when when dry apply refractory casting cement to the inside over the chicken wire? I do want to fabricate something that I can place inside to cook steak on but mainly it will just be hotdogs and marshmallows. Lastly for decoration I thought about using 2"-3" rods of heat resistant glass pushed through the walls to make cool reflections and lights at night.
Again. Thank you for your time and knowledge.