How to Install Plumbing Vent Flashing
- 1). Install the roofing shingles only until the shingles reach the bottom of the vent.
- 2). Lower a preformed flashing vent flange over the vent, and position the flange on the roof.
- 3). Mark the entire length of the top of the vent flange on the roof's underlayment with a pencil, then lift the flange off of the vent.
- 4). Apply a coat of plastic-based asphalt roofing cement to the underside of the vent flange and across the pencil mark made in Step 3.
- 5). Lower the vent flange over the vent, and press the flange into the roof to seat the roofing cement.
- 6). Drive roofing nails around all four sides of the vent flange with a hammer for added security. Installing roofing nails is optional but can help guard against leaks.
- 7). Cut the roofing shingles to match the curve of the flashing with a utility knife, and continue installing the shingles up the roof.
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