I built my oven about 5 years ago but never finished the facade on the outside of the oven. I have kept a tarp over it, but it definitely has some weather wear and tear. I am putting a wall and roof over it in the next 6 weeks. There are a few small cracks in the dome and some mortar has come out between a few of the bricks. I started a fire in the oven this past weekend and smoke came out a few of the places in the dome. I'd like to fix this before I finish the oven. Any suggestions? Should I mix some mortar and cover the dome with it before I insulate it? Thanks for suggestions!