I'm installing stove pipe through my ceiling. Our home has a metal ceiling and metal roof with steel struts and fiberglass insulation between the two sheets of metal. I'm using a silicon boot on the roof to support the pipe penetration. My question is to the proper install in the ceiling below. Is a ceiling support box necessary, or can I simply have the stove pipe penetrate both sheets of metal to the roof and be secured by the boot only? Any advice would be greatly appreciated!