How To Flash a Vent Pipe

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	This is generally how the roof will look when a vent pipe is ready to be flashed. The underlayment nails are shown to give an idea of how to properly nail down the felt underlayment. The spacing between the underlayment nails should be about 12 inches. First, we'll check to see if we can install another shingle. It looks like it will be close.
	Since another course of shingles fit without having to make any cuts, let's move on to the next step.
	What we're doing now is checking to see if the flange (flat part) of the jack will come down far enough so that it extends down onto the exposure (visible part) of the shingle. Take the lead jack and slip it over the vent pipe (the dotted red lines indicate the vent pipe). See how the flange doesn't come down far enough onto the exposure? We need to add another shingle. Remove the pipe jack.
	Take a full shingle and butt it up against the downslope side of the vent pipe. Mark where the shingle needs to be cut. We can mark it with a lumber crayon, scratch it with a blade, whatever is convenient.
	Now butt the shingle up to the side of the pipe. Make sure it lines up with the next course of shingles. The blue circle indicates where we want it to line up. Make a mark where the downslope side of the pipe lines up with the shingle. The mark is indicated by the small red line.
	The dotted red line in this picture shows the approximate shape of the area we want to remove from the shingle. Let's remove it now.
	Here's the shingle with the piece removed.
	Now we'll set the shingle in place and nail it down.
	Now let's go ahead and put another shingle in that same course. We're going to have to cut it, too.
	Let's go ahead and make our mark and cut it. It will look something like this.