http://www.AsktheBuilder.com founder, Tim Carter, is also a master plumber. He shows RARE video of plumbing vent pipes in an attic and walls before they disappear forever behind drywall.
Carter installed the vent pipes for this plumbing himself in a new home in central New Hampshire in the winter of 2016.
He talks about the importance of installing a full-sized vent on at least one stack all the way from the base of the stack up and through the walls and then through the roof.
There’s been a disturbing trend away from using a full-size vent in new homes. Many plumbers feel small 1.5 and 2-inch vent pipes will be enough to vent an entire home.
Small vent pipes can choke off on the inside with ice in bitter cold climates. When you use a full-sized 3 or 4-inch vent, it takes much more ice to close off the vent pipe.
The plumbing vent pipes create a pathway to let air from outdoors back into the plumbing system when water is rushing down the drain pipes.