Categories
< All Topics
Print

Can I build a full-size refractory pizza oven for less than $1,000?

Yes, you can.

You can build a nice, high-quality, 36″ round cooking floor cast in place pizza oven using a cardboard mold, non-refractory fireplace mortar, a real firebrick cooking floor, foundation, stand, hearth, waterproof enclosure, and very good insulation for about $1,000, plus or minus, using all new material, including shipping costs. See the spreadsheet at the bottom of this article.

Keep in mind that this article applies to a full-size, roughly 32-40″ round refractory oven. There are a couple of key things to understand.

First, in order to build a true refractory oven, there are some expenses that are unavoidable. Your oven will be heavy (a 2″ thick, 36″ oven dome weighs about 600 lbs by itself), so you will need need to pour a standard 5 1/2″ concrete slab and build a concrete block stand and hearth to hold the oven. That alone costs about $400. The foundation costs roughly $140 and the stand costs roughly $260.

You will need to build your oven dome with an inexpensive mold—either sand or cardboard, we recommend cardboard.

And you will need to cast your oven dome using a homemade mixture of locally sourced materials—fine mesh sand, Portland cement, hydrated lime and fireclay, plus a couple of fiber additives that improve the material’s strength that you order on the Internet.

Your cooking floor will be standard 9×4.5×2.5″ firebricks that should cost around $2.00 each. The bricks will be set on their flat/wide side, giving you a 2.5″ thick cooking floor, which is great. The cooking floor will last pretty much forever. Firebricks are readily available at your local brick/masonry supply store, and they should not require a special order.

The oven will be insulated with a combination of vermiculite or perlite insulating concrete, purchased either locally or online, in 4 cu ft sacks, and one roll of ceramic blanket insulation (50 sq ft, 24″x25’x1″). That will give your oven good, though not great, insulation, where it will cook and hold heat very well. If you’re lucky, and can find more ceramic insulation at a cost-effective price, including a second insulation blanket for the dome, and 2″ of CalSil boards for the floor, that would be great. Your oven would hold heat better. But if cost is your primary concern—the question is whether you can afford to do this in the first place, you don’t need to go to that step.

Your oven will be finished with chicken wire wrapped around the insulation blanket, covered with stucco purchased from Home Depot or Lowes, and painted.

Can you knock $200 out of this and do it for $800? I don’t think so. At least without scoring some cheap or free material on Facebook Marketplace. Some of the fundamental costs, including the foundation, stand, dome, floor, insulation, and stucco can’t really be reduced by 20%.

If you can’t swing $1,000, and still want a real refractory oven, you can build a 24-28″ oven without a stand, and with thinner materials for about $400. That would give you the option of setting your oven (yes, you can lift that by hand with two strong guys) on an outdoor counter. You can read our Can I build a mid-size refractory pizza oven for less than $500? article.

Finally, if you’re budget conscious (you don’t want to spend $5,000-$15,000 to install a precast oven kit), but not totally budget strapped, there are a couple of things you can do to improve this oven without the cost exploding in your face.

First, you can add more, and better insulation for a few hundred dollars.

Second, you can improve the quality of the dome casting. But this gets a little tricky. You can purchase commercially available refractory cartable from your local building supplies store, but it’s very (very) expensive, and usually very hard to find. Ask around for Harbison-Walker KS-4+, and see if they act like you’re from another planet. And be sure to calculate shipping costs. That can double the cost of the material. The basic math says that you need 600 lbs of castable for the oven dome, and if one 55 lb. bag of KS-4+ costs about $80 (let’s say $65/bag, plus shipping), and you need about 10-12 bags for your dome, that means the cost of materials for the dome alone is about $800. That’s a lot, particularly compared with the roughly $150 cost for the homemade castable material.

You don’t need to worry about your firebrick cooking floor—that will be great. But you can set aside some additional budget for trim and decoration for the oven open and the oven landing.

Now all you need to do is work you butt off building the thing. But if you do, you will absolutely love it, for years and years to come.

Homebrew Castable Pizza Oven Material Costs
#PriceTotal
Foundation
Lumber 2x6x96”4520
Concrete mesh12020
Concrete 80 lb14798
Subtotal138
Stand
Blocks 8x8x16503150
Lumber 2x4x96”6318
Hardibacker 36x60x1.5”21326
Concrete 80 lb10770
Concerete mesh 4x7’12929
Rebar 48x0.5”4520
Subtotal313
Oven
Firebricks 9x4.5x2.5 floor502.04102
Perlite 4 cu ft floor insulation355165
Blanket 1’x24”x25’ dome insulation1100100
Portland cement 95 lb12020
Hydrated lime 50 lb22550
Fireclay 50 lb22346
Sand 300 lb12626
Chimney 6x24”14545
Subtotal452
Enclosure
Chicken wire 50x2’x2”11616
Sakrete bonding cement 50 lb430120
Subtotal136
Total1039