My 27" build in Albuq

[david s]

In defence of smaller ovens because of the reduced fuel consumption it means they get used more frequently. Fuel consumption is related to chamber volume which means a 20% diameter increase leads to 75% volume increase. A small oven means less labour to build, less weight to support, less materials required, which also means lower costs. Large oven owners won’t feel inclined to fire up their ovens on a Friday night just to cook 2 or 3 pizzas for a small family. Generally most oven owners cook only one pizza at a time anyhow. My oven is only 21” internal, yet I comfortably cater for 30 guests and have done for over 50. What you do need to do is make people share whatever comes out of the oven rather than cook individual pizzas for each guest. This is a more enjoyable eating experience anyway.

[mongota]

I highly recommend that you take a second look at the functionality of your 27" oven. From the size of the opening and how it'll intersect the 27" dome to how much (or how little) floor space there will be too cook pies with a fire off to the side.

You're so early in the build. So early. I'd consider taking a step back and considering how you can modify the base to get a larger oven. It'd be painful short-term, but if you can't pour a second cantilevered slab over your existing slab due to height, I'd even consider demolishing your existing slab then reforming and pouring a cantilevered slab over your current base.

Dang, if I lived nearby I'd come over and lend a hand.

So much effort goes into building one of these things, I'd hate for the end product to not live up to your needs.

[UtahBeehiver]

You can always pour a 3" 5 to 1 pcrete first You need 5 to 1 for strength, topped with the 2" CaSi. You need to consider drilling in some weep holes in the base for egress of water. It will get in there and wet insulation is one of the main reasons of poor over performance. 3/4" revel is okay, bare minimum. Arch opening height should be 63-65% of dome height although I have seen a little fudging on the this rule of thump. Width is builder's discretion.Dome insulation is just as important as floor insulation. You can always do a cast oven which will gain you a larger ID since cast ovens are abt 2" plus in thickness. David S builds really nice and small ovens. See his threads.

[JDub36"]

Hi,

I left the forum for a while, after buying some initial materials and initiating a post (JDub36") and getting stuck on design issues. The 36" has been reduce to 27" due to following the Oven Plans v. 2.0, p.17 stand/hearth dimensions without reading anything on the Forum. Built the stand and the hearth as spec'd on the Plans only to realize a 36" oven won't really fit once you factor in the walls (4.5"), insullatioin (3") and render (1"-2" depending). So... have come up with a 27" floor diameter and have been laying out bricks to figure out how much of a landing, if any, I can get away with. Will probably just end up with no landing but have the flue gallery right up to the front edge of my corner build hearth (thank you rsandler!).

A little background: the idea for a WFO came probably 6-7 years ago and was to be part of a whole backyard kitchen. I laid a brick patio, borrowing a really nice wet saw that is now mine. The saw will be very nice to have for the oven bricks. The kitchen incorporates an old battleship of a charcoal grill/smoker that was my Dad's and also a Weber charcoal grill, That's right, homey don't do gas grills! A new job and other life commitments have delayed this project, but the WFO is now getting started. I poured the hearth last winter and am now getting going on the oven.

The corner hearth turned out with dimensions of 47" on the long sides by 31" on the short sides with the front face 22-3/4". I built the stand with a bunch of cinder blocks I picked up off of craigslist. The blocks weren't all necessarily the same size but they were spaced to achieve the desired outside dimension, hence some good-sized gaps that will need to be filled in when final finish is done.

A drawing on the Minnesots 36" build site helped me finally decide on floor dimension of 27". In the attached photo, I'm playing around with bricks to come up with a 16"opening although I realized that I have 16" at the inside arch and the largher opening, towards the front is 18". Probably too big for size of oven? Is 16" even too big? Also, what is standard/typical lip on inside arch to accommodate a door? I've got about 3/4".

Because of limited length for landing, and the plan to have a flue gallery/landing (if that makes sense?) I plan on having a 5" chimney. That sound about right?

I'm so far only planning on having the oven sit on 2" of FB. Firstly because the source I used was so darn expensive (~$170 incl shipping for 2"x 24" x 36"-2 pieces) and also not sure I really need the oven to stay hot for 3 days after backing pizza. I absolutely do want to bake some bread, but how soon will it loose sufficient heat to not be able to bake, say the day after, with 2" FB bottom?

I tried to buy some more Insblock 1900, but the source kind of wigged out, said they didn't really like shipping it because it's brittle and breaks into pieces....

Anyone have a reliable source for more FB, should I decide to increase bottom insulation from 2"?