[Nick]

Thanks for your comments. I'll pass them on the Brian, the builder, when he returns. Which should be tomorrow. I hope.

To answer your questions:

They are red firebricks.

The plan is to fill in around the oven base with stone and topsoil. Brian stuccoed the outer wall to help protect it against dampness. There is a drain in the floor, which will be brick over the concrete.

I'll probably just plant grass around the edges.

There is a flagstone patio near the oven pit. Half the patio was dug up for the new septic system (old tank removal, new piping only. The drainage field is plenty far away from the oven!)

I never really liked the flagstone. I'm considering tearing it all up and replacing with used old bricks, like what's around the oven.

Thanks!

DB