Lead pipe flashing needs to be installed around a vent pipe where it protrudes through the surface of the roof. This flashing is important, as it provides a cohesive and durable layer of protection. The flashing will make the installation water resistant as well. Lead flashing is fixed around the entirety of the vent pipe where it is exposed above the roof. It can also be made to blend in with the surrounding roof shingles. Lead pipe flashing also consists of a sheet of metal on the flange of the vent. A lead jack is used to cover the exposed section of pipe. Done properly, this installation will form a protective shell over the vent, protecting your roof from weather damage.
Step 1 – Determine the Location of the Lead Jack
When you are attaching the shingles to the roof of your house, start at the bottom ends and work up towards the vent pipe. The lead jack should be placed over the vent pipe to determine whether it fits as it should or not. Make sure that the flange of the lead jack fits squarely over the shingles. The flange should be exposed on top of the line of shingles that it overlaps. There should be no gap in the roofing between where the shingles are installed and the vent. The purpose of the flange is to make the area surrounding the vent watertight, so make so that it overlaps the shingles by at least a few inches. When you are satisfied with the fit, remove the lead jack for now. Ideally, the shingles should be cut to fit around the vent pipe as closely as possible. Cut the shingles to fit if necessary.
Step 2 – Place the Lead Jack
Put the lead jack back onto the vent. The top of the course of shingles should be just above the pipe, and the jack needs to lie on top of this, overlapping the course of tiles right above. Overlapping the flange of the lead jack onto the roofing shingles, fasten the shingles in place. Use galvanized roofing nails for this.
Step 3 – Cut Away Any Excess Shingle Material
With a marker, draw a mark on the shingle where it touches the vent pipe. This shingle will now be within the tube section of the lead jack. Use the utility knife or other appropriate cutting tool to cut away the excess material. You will be cutting the shingle starting from the lower end at this point. Make sure that the shingle fits around the pipe properly.
Step 4 – Finishing Touches
To complete the protective shell around the installation, carefully fold down the tops of the lead jack into the end of the pipe. This will complete the protective shell, making it water resistant and finished in appearance.