Roof flashing questions

what kind of flashing is it the norm. flat piece with a cone ? clearance should be 2" alll around. My flashing(excel) has a cone that goes over the pipe and the bottom piece is square and boxy.(word?) it is flat on the upper roof part and tapers up to around an inch and a quarter on the bottom edge so I could cut it to fit the ribs in my metal roofing. since I used a cathedral ceiling supposrt I had to cut a 12"x12" hole and the flashing covered it nicely.

Remove shingles around the area where the chimney is coming up and through. Try not to take too many below the chimney. Find the center of the chimney and make a mark on the roof. Center flashing to the mark and reach inside and trace the oval that rests against the roof. Remove flashing and cut out oval. Run a length of chimney up through the roof. Check clearances and correct if necessary. Roof in up to the bottom of the oval cut out. Apply a "u" shaped bead of caulking around the bottom half of the oval cut-out. Drop flashing down over chimney and onto the bead of caulk. Square it up and tack it down with a roofing nail in the upper most corners and one on each side halfway down. Now apply an upside down "u" bead of caulk starting from just under the next course of shingle so it is hidden. Finish roofing in over that bead and make fancy cuts to keep the shingle fairly tight to the upper half of the flashing curve. Put the storm collar on down tight. Caulk top of storm collar. Caulk any worries and yer done.(the flashing that is...)

Yeah, sometimes if the decking is thin and bouncy I'll add some support or instead of trying to nail the flashing, I'll use screws. If it's a planked roof, I'll always add support to help even out the boards that always spring a bit when you cut through. As for caulking, use something gooey and non-hardening in the hidden beads. Use a thermoplastic like Mulco Supra for a nice rubbery seal on any visible beads. Match roof color or use black.

If you save the shingle parts you cut out of from in the hole area, rub the face of them together (granular side) over a pc of paper or something to collect the granulars that fall off. Do this till ya have a small hand full or palm amount. After you are done caulking, any caulking on the top side of the roof, you can sprinkle the granulars over the caulk, lightly press them onto the caulk and it no one will ever see the caulk from the ground. Works very well.