The Difference Between Vent Stacks and Stack Vents


There are many differences between a vent stack and stack vents. To make sure you’re up to code, our Tampa plumbing experts have outlined these differences and the requirements that are essential to meet with each.

Vent Stacks

A vent stack does not carry waste and is only a stack for venting. A vent stack is required for every five brand intervals or more. Every vent stack that you have must connect to the bottom of the drainage stack and has to be located downstream within a distance of 10 times the diameter of the drainage stack. By doing this, you decrease the risk of pressure affecting the system’s traps.

At least one main vent stack is required for every building that has plumbing when connecting separately to the sewer for the building or its septic tank. The stack has to run the most direct route through open air or be ventilated to extend to open air.

Stack Vents

A stack vent is the extension of the waste stack to provide venting. The uppermost part of the waste stack that connects to the uppermost part of the roof is the stack vent. Our Tampa plumbers note that the functions of a stack vent and a vent stack are very similar, but the biggest difference is that the stack vent is a direct extension that must reach outside air.

Stack vents are only used to vent sewer gas and to allow drains and toilets to operate efficiently. There has to be a supply of air to have things work correctly. If you imagine turning a can of soda completely upside down, it takes longer for all of the liquid to escape. If you poke a hole into the bottom of a can, the soda will leave the can much quicker. This is how a stack vent works.

With most plumbing problems, the stack vent is involved because pests like to get into the vent and clog or block it by setting up their home. When a blockage occurs, gases can back up and be damaging to your health and have a foul odor.

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