When you reach the vent pipe you then insert a vent pipe flashing and continue adding shingles around and above it as normal.
Replacing roof flashing vent.
Pry and lift off the flashing.
Replacing a dry rotted vent pipe flashing since the rubber material that fits around the pipe is susceptible to breaking down from uv sun rays it is only a matter of years until you will need to replace the flashing.
Position a new vent pipe flashing over the vent push it down into place and nail where shingles will cover it.
Pull the old flashing up over the vent pipe and scrape any old caulk and debris off the roof.
Roof flashing sometimes develops holes often from hailstorms.
However there are limited circumstances where a roofer may decide to reuse flashing.
Plumbing vent pipes that extend through the roof come with metal flashing or rubber boot type flashing to seal the penetrations.
Cover the screws with a waterproof substance such as a silicon seal.
To replace flashing around the vent pipe first remove the shingles covering the flange at the back and sides.
Figuring that the rubber collar on the new flashing may split before it s time to strip and replace the roof shingles another 20 years hopefully i first seal the vent pipe to the metal of existing flashing with protectowrap s form flash 2 flashing tape.
On a typical re roofing job where you are replacing an old or underperforming roof it is wise to replace all flashing.
Replace all rubber boots and replace metal penetration flashing.
Pull or cut off any nails.
Replace the shingles and cover the nail heads with roofing cement.
The collar and sleeve looks like the new construction version without the roof flange slides over the plumbing vent pipe and damaged boot flashing.
Old flashing may begin to fail before the new roof s lifespan is over.
Slip a flat bar under the edge of the vent flashing and pop the nails up photo 1.
Slide the new flashing over the vent pipe and under the shingles above the pipe.
The home mender shows how to replace a broken pipe collar on a shingle roof.
Click the links below to see inside dustin s toolbox ps roofers charge up to 2.