Originally Posted by Thermal Mass
It gets amazingly small in there in a hurry!!
Keep in mind you are not working on the ground, but over a dome that is likely growing to 5+ feet from the ground.
Your back and stomach muscles will remind you daily....
The foam is lightweight, sturdy, and stands on it's own.
You will also noticed we used it for forming the arch over the flue so if you buy one sheet you will use most of it.
**One tip on the flue arch, we sandwiched multiple pieces together for the form but you almost MUST CUT THE MIDDLE PROFILE OUT (except for the outer piece) or good luck getting it out without a real fight (drills, sawzall, chain saw, ???)!!
Maybe make a couple and miter so they fit in the center if you think you need to.
One form worked out perfect for us and lasted the entire project.
Thanks for the advice. I will definetly keep this in mind. I figured i would use plywood since i have so many, but i guess a foam would be easier.