I ran my 6" single walled pipe through an old 3 foot long piece of 8" Metalbestos that I installed some spacers (bolts) inside so the 6" pipe would stay centered. The 8" is 2" from any wood, and is flashed on top using some aluminum sheet. When I am not using my arch I remove a section of pipe inside the shack and drop down the top sections and my "oversized" rain hood closes off the 8" metalbestos pipe top to the weather. Second picture shows it in the closed position. Jay

19 Sugar Shack Chimney (3).jpg 23 Cupola Finished (1).jpg