Wednesday, January 31, 2018

Brick Ovens Survive Apocalypse

Imagine your city two-thousand years in the future.  Imagine, or not, some event that would cover the city in twenty feet of ash.  Then imagine, uncovering the city.  What would you  find?  What would be left?

Pompeii, Italy is a post-apocalypse city.  Mount Vesuvius erupted in AD 29 raining hot ash on the inhabitants of Pompeii.  Those that didn't leave early became entombed.

Twenty-six bakeries survived.  Rather, twenty-six brick ovens survived; the bakers didn't.

Fast forward almost two millennia.

Fires sweep coastal southern California.  Many homes burn.  The Ventura brick oven I built, having a stone roof as well as masonry interior and exterior, is intact.

Some things are meant to last.  Our homes certainly.  Our friendships hopefully. Brick ovens, definitely.  

This ancient cooking device is nearly eternal.  Whatever your vision of apocalypse, be sure, brick ovens will be there afterwards.

Monday, January 29, 2018

Colonial Era Brick Ovens

Jan Steen: The Bean Feast
Imagine if they had pizza!
I have on occasion been asked to look at a colonial era brick oven, most often built on the left side of a fireplace/hearth.
These were used to bake bread, beans, and food other than pizza; try to imagine Puritans wanting pizza!  Heresy.

The conversation with owners of the ovens today goes like this:  "I can't get the oven hot enough for pizza!  What's wrong with the oven?"

Puritan family waiting for the oven to get hot
Answer: Bypassing a long historical explanation on why colonials didn't make pizza, I explain that the fireplace/hearth was burning all the time.  Colonials cooked everything on it, either in a pot hung from a hook or on spits.  The oven, part of the overall masonry, was always warm, may 180F or more.  A shovelful of coals from the fireplace would bump the oven up to baking temps and the ambient heat of the fireplace would prevent it cooling down quickly.

Trying to get a cold colonial brick oven to baking temps when there is a ton of cold masonry sucking the heat from it, is like shoveling snow into the wind.

Fiber blanket insulation over dome before roof goes on
That is why I isolate my brick ovens from other masonry and insulate them well.

The advent of the cast iron stove must have been as miraculous to colonials as the smart phone once was to us.

Workshop sponsored by Castine Historical Society
Last summer, I did happen upon a workshop in Castine, Maine given by an old-timer mason whose predecessors built colonial ovens.  It was interesting to see how casually he placed the bricks.  It reminded me how both practical colonials were and how imprecise an oven can be and still work.

Oven built on a sand mound form (later removed)

I personally get a kick out of making perfect domes.  Go figure!

Elongated dome TBO 48"x60" St. Charles, MO

Friday, January 26, 2018

Brick Oven Firing and the British Thermal Unit

A dry piece of hardwood has a certain amount of BTU potential.  To extract the maximum BTU's (British Thermal Units...not important really) from a piece of firewood may or may not be your goal when firing your brick oven.  Because I cut my own firewood and I've burned my own calories cutting that firewood, it is mine.  (Geek alert* One BTU=0.25 Cal...again not important to brick ovens).

 Therefore, having a relaxed firing where the addition of dry firewood to the oven is done slowly, will result in very little wood used to achieve high temperatures in the oven.  Recently, I got my 36" oven to 700F using six (6) pieces of firewood (average 5 pounds each).

I've noticed that the early fire is the most inefficient.  This is because the volatiles in the wood burn at different temperatures.  The early firing can only combust a portion of the volatiles.  The rest goes up the chimney.  Later, at about 400F, a second group of volatiles combusts as well, releasing more heat.

Back when I was a potter firing a wood-fired kiln, there was a third group of volatiles.  I remember putting a two inch diameter stick in the firebox when the kiln was about 2000F and flames would shoot through the entire kiln, up the 20 foot chimney and be seen spurting out the top.

BUT DON'T GO THERE with your brick oven.  2000F is white hot and a brick oven should never be close to that temp.

Gray, lazy smoke and a certain fuel-like smell is a sign that you have too much wood burning in the oven.  Let it clear.  That is the time when you're getting efficient heat and maximum BTU's from your  wood.

Thursday, January 25, 2018

Accentuate the Positive

TBO 36 with intentionally designed brick pattern patio
Oven is built on existing ledge outcrop

The following blog post arrives from my experience as a landscape designer and often applies to projects where a brick oven is being built.   

Perceiving an object requires that we distinguish it from its surroundings. The joke about a blank piece of paper being ‘a polar bear in a snowstorm’, applies to our perception.
Placement of TBO 36" in Ventura CA to frame view.
Oven is adjacent to home's kitchen
Painters and sculptors refer to positive and negative space. Positive space is the object we are able to perceive. Negative space is the background that allows us to see that object.

Siting the oven as a positive element is especially important with outdoor projects.

Positive and Negative space built into the oven design enhances the stonework
A yard or deck becomes 'complicated' when objects are placed on or next to it.  Choosing a location that doesn't 'interrupt' the space is important.  If the choice 'compliments' or 'enhances' the space, all the better.

Choice of stone color and shape accentuates the design.
We see the arch clearly because the stone is more formal
than the surrounding stonework

In landscapes, the tree is the positive and the sky is the negative.
Outdoor classroom by
Applying this to landscape design, we may choose to remove masses of confused greenery in order to accentuate a specimen tree. We may also take advantage of a mass of greenery by planting or building a contrasting form in front of it. We might ‘cut’ a hole in the greenery to form a dark shadow. Each of these changes creates the negative space needed to bring the desired focus to the design.

My former garden in Waterford, Maine

the house I designed and built in Lovell, Maine
Homes provide positive space; ponds and shadows negative space
Foreground plantings accentuate negative space.

Wednesday, January 24, 2018

Brick Oven Cooking: part seven

Every once in a while I get to visit an oven I built.  If I am fortunate, I cook in it along with the owner or chef.

I just spent a great couple of hours with Chris Dill, Executive Chef at Brewster Academy in Wolfeboro, NH baking foccacia.

Five years ago, I built a 54" brick oven in the dining facility.  Since then, it has been used for many purposes, especially Friday night pizza, slow roasting meats, and more recently, Wednesday focaccia.

Chris made a large tub dough and it sat beside the oven.  Multiple ingredients were available as the light and varied toppings customary on focaccia.

At 11 am, just before the lunchtime rush, when 350 students and faculty arrive, we began making focaccia. We went non-stop until 1pm.  I think we made about forty focaccia.

Every chef, pizzaiolo, cook has tricks.  Chris showed me a few that I'll carry with me on future focaccia adventures,
Grazie Chef Chris.

Tuesday, January 23, 2018

Brick Oven Dimensions

Once the conversation with new customers approaches the planning stages, the subject of oven dimensions becomes central.  This is due to space restrictions or location choices.  Fortunately, dimensions, although they vary, can be very specific yet somewhat flexible.
Most outdoor installations focus on exterior design, which includes enclosure shape and roof design.  Indoor installations need to conform to local codes, means of routing the flue, the available space in the house, and adjacent room elements.  In many indoor installations, the volume of the oven is placed behind the wall of the room, either on its own foundation or in a space that can afford to be occupied.  Nearly every situation has its solution.

The evolution of each customer's design is a conversation involving these type sketches and more real-time visual examples of the kinds of materials, textures, and shapes the final oven will possess.
Exchanges with customer's architects and perhaps engineers may enter the process.  I supply spec sheets on all materials so that the ovens comply with local codes.
Compare these to the Brick Oven Face post.

The following CAD designs will illustrate the dimensional aspects.  Examples represent different past TBO projects.

indoor residential TBO 36"plan
TBO 54" Commercial: Face on public side, back in prep kitchen
Outdoor TBO 48"
Outdoor TBO 48" 'Greek' style

TBO 48" restaurant, designed to building specs

Indoor design

Indoor design

Off-deck TBO 36 design

TBO 36 Indoor high ceiling design

TBO 36 Terrace corner design

Thursday, January 18, 2018

Brick Oven Faces

Building custom brick ovens offers the opportunity to design the exterior of the oven to the tastes of the owners.  This means variety.  Although some of the ovens I've built have similar face arches, I've played with the central theme.  Others are one-of-a-kind 'inspired' designs.  Either way, the face speaks to the owner and frames the fire.
2000 year-old oven in Pompeii, Italy

TBO 54" at Pietree Orchard in Maine

TBO 36" Ventura CA
TBO 36" NH

TBO 48" Maine
Some of the designs originate with a cultural context.  Some originate from the qualities of the materials. And others are a direct result of the customers wishes.
Original TBO 36" Portable
TBO 48" portable CT
TBO 36" Art Deco

TBO 36" in colonial

TBO 48" in Restaurant

TBO 36" outdoor NH

TBO 36" MA

TBO 54" Dining Facility

TBO 48" Baker's Oven

TBO 36" in my house

TBO 36" Maine

TBO 48" MA