Taking it home

Here are the first, second, third, fourth, fifth, sixth, and seventh posts in this series (you can also go to the “bread oven” category, in the lefthand navigation menu).

With the outer walls bricked in, Jan had one engineering problem to solve before starting on the domed roof of the oven. He realized that if he built the arches resting on the single-thickness brick walls, the weight of the dome would press the walls outward and the dome would eventually collapse.

After conferring with his father, a former civil engineer, they came up with this strategy:

He poured concrete pillars into the four corners of the outer oven walls. Then he ran rebar around the inner perimeter, and tied it into pillars and brickwork. This keeps the brick walls from splaying outward.

Note the vermiculite insulation which eventually filled all of the space between the outer walls and the oven chamber. This is another contribution from one of our neighbors, who runs a wholesale nursery. This oven is the most collaborative project I’ve ever seen in any neighborhood I’ve ever lived. (Everyone’s trying to guarantee their share of the bread . . . )

After diverting eventual collapse, it was time to install the dome.

Jan built a big semicircular plywood form, and mortared the bricks over that, removing it when they dried.

At the rate of about one row per day, the finished product emerged.

Jan is waiting to close up the back wall of the dome until he’s fired the oven a few times, to make sure all of the moisture has been evaporated from the space. But that’s all that’s left.

Close to 6 months, hundreds of man-hours, and a couple thousand dollars later, we have ourselves and oven, ladies and gentlemen. And a damn fine one.

It just so happened that the day Jan was ready to fire it up was the morning of our first freeze of the winter. How perfect is that? We’re all in awe of this accomplishment, no one more so than Jan! And we are so grateful for the way it has brought our neighborhood together. We are looking forward to many hours sitting around the oven with our friends and family, making pizza and bread and sharing them out.

Bricks for breakfast, bricks for lunch, bricks for dinner

Here are the first, second, third, fourth, fifth, and sixth posts in this series (you can also go to the “bread oven” category, in the lefthand navigation menu).

So, everything so far took about three months. Admittedly, the families (read: wives) were growing weary of the missing husbands. But nothing prepared us for the epic slog that would be the Bricking of the Oven. The four sides took two full months. The dome took another two weeks (a later post). The good thing about the process was that it could be done in small increments. So Jan would come home from work, throw on his overalls (yes, he bought overalls), and lay down one row of bricks. I have never seen anyone so diligently devote all of his spare time to one activity. But even he was starting to go a little crazy.

Jan widened the form used for the oven entrance arch, and made the lower arch with it.

During this time, he also extended the oven floor out through the entrance, using fire bricks.

The slot you see is where the coals and ashes will be raked out of the chamber and onto the ground (or into a container).

Once again, the same arch form was used for this upper arch.

As the walls go up, there is an open space being created between the chamber and bricks. This space will eventually be filled with vermiculite. More insulation.

The open space above and between these two arches will remain open as the chimney.

Our neighbor has taken up blacksmithing. For real. He has a coal-fired forge in his back yard. Anyway, he gave Jan some railroad spikes to use as hooks on the sides of the oven. I love these. They’re so pragmatic. And yet, so cool.

I’ll wrap this piece up with a mea culpa. For the most part, I’ve been the staff photographer on this project. So I came out to capture the rising walls. Now, I’m short. Though I’m tall enough that my feet reach the ground, as my (short) grandpa used to say. Anyway, I wanted to get a picture of the space between the chamber and wall. So, being the former-rock climber that I am, I put my foot on something slightly higher than the ground, grabbed the corner brick, and flagged my foot out for counterbalance.

Off pops the brick, pried loose from the still-wet mortar (bottom right). (sigh) I put the brick in Jan’s hand and slunk back inside.

Insulation

Here are the first, second, third, fourth, and fifth posts in this series (you can also go to the “bread oven” category, in the lefthand navigation menu).

With the oven chamber completed, it feels like we’re in the home stretch. Time to add mass to the oven, to retain heat. This thing is going to get crazy hot. Pizzas are cooked at 650-800°. The oven also needs to maintain high temperature for a long time. Bread is cooked around 500°, after the coals are raked out of the oven. Lots of mass and insulation ensure consistent results.

First, Jan built a removable plywood form, into which the concrete would be poured.

Then Ken and Jan wrapped the chamber with tin foil, to shield the bread from cosmic radiation. Actually, it’s to prevent the concrete mass from adhering to the chamber structure. This will allow expansion and contraction in the chamber, without breaking up the concrete layer.

Next they replaced the form, and inserted rebar around the chamber structure.

Please note the stretch of space on the side of the form where there is no 2×4 supporting the plywood. This will become important later.

Next, massive quantities of concrete were mixed and shoveled into the form. When this project started, Jan and Ken were carefully measuring water to add to the concrete mix. By this point, they were mixing their own concrete from scratch, and eyeballing the water from a hose. Skills have been acquired.

Concrete is heavy. Really, really heavy. So as the boys were shoveling, they began to notice that the sides of the plywood form were bowing out. Note to those who come after: reinforce the plywood along the entire length. Otherwise, you’ll need an emergency retrofit:

The good thing is that this will all be covered up by the outer brick-work. So no harm done. The form came off a couple of days later, and our commitment level ratchets up another notch.

Notice the inset wooden form at the top front. That is where the chimney will be.

At this point, Jan and I reflect on permanence and attachment. He told me we could never move now. This is a funny thing to say to me. I have never in my life lived in a house for longer than 4 years. We, as a couple, have moved 6 times into 7 houses in our 9 years together.

“You told me that this oven was built on a floating slab, so that it could be detached from the base and moved,” I say.

“Well yes,” he says, “moved across the yard or something.”

“Across the yard?” I am incredulous. “What the hell good is that? Why can’t we take it with us?”

“This thing weighs as much as a Hummer!”

“I see Hummers moving around all the time.” Too often, if you ask me.

“But they have wheels!” Now he’s incredulous.

“So, get some wheels for this thing. We’ll hitch it to the van.”

If we do end up hitching this thing, I promise I’ll share pictures.