Vent stack and stack vent, are they the same? It seems like both plumbing terminologies pertain to the same thing. Unless you are a plumbing expert and familiar with the terms, you may have to pause for second and think about it.
It may seem like they are the same thing, but they are not. So, what is the difference between a vent stack and a stack vent?
Vent stack. This is a vertical pipe that is only used for venting and goes upward from the drain piping. It works to dissipate odour outside the home. Vent stacks are primary vents and accept connections from other vents in a plumbing system.
Stack vent. This is used for both drainage and venting. The bottom portion is a soil pipe for drainage and the top part is a vent. This is the kind of primary vent most often used in residential plumbing.
Plumbing vent pipes are designed to let fresh air into the plumbing system and help the other drains in the house to work properly. Plumbing vents need to be straight on the vertical to avoid any vapour locks from occurring.
Can a plumbing stack have bent? When there is a bend in the vent pipe, moisture collects and is trapped. Because the vent pipe is the warmest pipe in the house all year long, the moisture that is trapped in a bend may turn to vapour and cause a vapour lock. This vapour lock will prevent the vent pipe from working properly.