fireplace and oven on top

[mikmik]

Hi all,
need help to double check before construction begins

right then,
As part of a design for a garden, a fireplace was planned, so 8inch agg put down and 8inch concrete put down (no rebar) to support the brick structure which was going to be about 4foot tall tapering to a pot on top as chimney, the fire place, about 30in wide by 60in high approx.

The concrete has been down for a month.

last 7 days the owner asked for a pizza oven aswell in the same space, so steep learning curve begun.

It was mentioned that it's not a great idea to have an oven on top of a fireplace, from what I've read here it has logic, but space and time are limiting factors.
So it will have to.

width and depth of the foundations also affect design, As the footings are approx 55in (140) wide x 30in (80cm) deep. Could the weight on the footings possibly be a problem? because of the extra weight?

The pizza oven has to be half barrel shaped 18in high with door 15in
(i think i will post this in another part of the forum aswell as this has its own problems).

The question I need help with right now concerns the roof of the fireplace, ie directly above the flames.

Because of height restrictions (ie don't want the oven too much over 3feet high) a flat ceiling for the fire was suggested, using reinforced concrete lintels and because of depth limits, the flue to be directed to the back and up as close to the wall that it's being built against as possible to allow as much space on top for the oven as possible.
Can anyone see problems arising with the lintels?

[mikmik]

ok, think ive changed design a bit, going to have really shallow arches of engineering brick with ceramic blanket on top of them, then load bearing lintels, so no worries of loss of integrity, and spalling the lintels from fire exposure.
Sounds better, doesnt it