Tuesday, May 29, 2018

Brick Oven Chimneys

Any brick oven with a mouth and a face, which between them creates the flue, needs a chimney.
Vented into existing chimney
The chimney serves to move the smoke away from the face of the oven and the baker.

The height of the chimney determines how far away the flue gases go as well as the draft of the chimney.

For indoor ovens or ovens attached to homes, the 2 in 10 rule applies; the chimney must be 2 feet above the ridge of the house or 10 feet away from the building and roof.  Higher chimneys create better draft.

short chimney
Chimney materials vary.  Outdoor ovens with low chimneys typically have clay flue tiles with stone or brick exteriors.  Indoor chimneys typically have insulated stainless steel chimney for ease and safety.  Occasionally it is possible to vent the oven flue into an existing masonry chimney.

metal chimney and two makeup air ducts
A chimney chase is a wood structure built around the metal chimney to either conceal the metal or create a substrate for a stone or brick veneer.

All chimneys are capped with a metal or stone cap.

Stone veneer over wood frame chase

Metal chimney alone

Vented into existing chimney

Saturday, May 26, 2018

Triple Arch

Admittedly, I enjoy building arches and domes.
In this current project, I've built three separate arches.  This will enable the owners to both close the mouth (which isolates the dome) as well as the face arch (which is in front of the flue).  This does not replace the damper in the insulated metal chimney which will still function to close the chimney when the fire is out.

As will all current ovens there are two air channels on either side of the mouth.  These will be closed by specially cut bricks and the second door as well.

Tuesday, May 8, 2018

Dome Was Built in a Day

Judging from the number of visits to posts describing details of building brick ovens, I can guess that a fair number (New Englandese for 'a lot') of people are looking to build their own ovens.

In the past, I've spoken or consulted with people who have built their own and the consensus is that it takes a long time, like months, for a owner-builder to finish.

This may be the reason that on many occasions where a project involving both extensive masonry and a brick oven I am asked to build the 'core': the technical part of the oven.  I've worked with expert masons all over the country because it made sense for them to pass on building the central part of the oven to me rather than build a one-off themselves.

In the case of a homeowner building one him or herself, the equation that measures the time and precision it takes for a one-off is weighed against the cost of my building the core.

In addition, I've offered advisories suggesting that a professional mason, although expert at fireplaces, walls, etc., if hired, may not know the engineering and physics of brick ovens, thus leaving the owner with a brick oven that is NOT a brick oven in the functional sense. (Was that a long enough sentence???)

This project in New Hampshire, is a 42" interior diameter oven core that was completed in one long day.  Additional work to bring it to completion is needed, but it demonstrates the efficiency of experience.