Here's how I did mine. This is a big job. I have to knock a hole in a perfectly good roof, get everything lined-up and hope all goes according to plan. My neighbor came over to oversee and give advice as he'd done this kind of thing before... To find the center-mark where the center of the stove pipe would be I used string and a plumb-bob type thing. Once I was happy it was drill baby drill! The hole I started with the cordless drill was a small pilot hole. Then, getting on the roof I traced a circle using the triple-wall pipe. This is what will be penetrating the void and keeping the ceiling from getting too hot. Once the circle-mark was made with a used a reciprocating saw to cut it out! A few minutes later I tested the triple wall pipe until it had some gap, then I went back inside the cabin to fit the ceiling insert that the triple wall would 'sit' onto. I put a few screws into my ceiling beams to secure it. My friend helped as well with holding it in place. Now came the first great challenge! The triple wall had to go inside a stove pipe (as far as I recall) which was an incredibly tight fit! The only way it (the triple-wall) would slide down it was to get out the maul, use a batton for spreading the blows, and get pounding! I was almost sure the triple wall would split open or the ceiling insert would rupture etc, but apart from a slight deformation at the base of the stove pipe all was well. I was a bit tired but pressed on. The final pieces were the flashing, extra height pipe, and cap. The diameter on my stovepipe was six inches. The diameter on the flashing was... Six inches! Bad move, this, when combined with trying to fit it over the triple-wall was impossible. No matter how much I cut and cut the flashing away it was no good. The flashing was too small, despite taking it all the way to the base! With anger clouding I hurled the flashing off the roof. Rainfall was looming and I did my best to waterproof the area. Ordering in a larger eight inch flashing was vital, unfortunately the nearest city with one to ship in had a five day delay! There was nothing for it but to wait it out. To add to my predicament my 6 to 5 inch connector would not fit and I butchered it to the point of destruction. Another piece of metal went winging off the roof! I stuffed the entire cap and pipe in for the sake of appearance and ordered in a six inch cap as well! Drip Drip Drip went the bucket through the night, to add to the grim vibe the bucket tipped over and my floor got soaked! But the day came and, after being initially told the items had not arrived (and nearly going mad in the process), I had my pieces to fit finally! LOL. The flashing side over the triple wall with a 1/2 inch gap. This was not an issue as I had this goopy cement stuff for sealing up the flashing nicely. Firstly I had to screw it into place with my roofing screws. As I was doing this I should add it was starting to rain! So there was an element of urgency about my actions! Then I got my grease gun going and layered on the black goop. This stuff was like toxic-sludge in some ways! After a few runs of the stuff on the lip of it and around the penetration I was confident it would be water proof. I stuck the chimney cap in last via the connector and the fit was good. The stove pipe assembly was complete. I felt ill after the session though, despite being in the open-air on my roof! I later learned that the chimney cement goop had tar in it! Still as the rain came down heavier the stovepipe suffered from no leaks! I should add that the entire stove pipe assembly was a mish-mash of used and new materials. Yet the new materials exceeded the cost of what I paid for the woodstove. It was time to fire up the woodstove and see if it would explode, burst, rupture or leak!