Plumbing Rough In – What is a Plumbing Stack (EP8) - 2023

Summary

This video offers an in-depth look at the plumbing stack, also known as the soil or waste stack, which is a vertical pipe crucial for carrying wastewater and sewage to underground drainage. It explains the stack's purpose, the importance of sizing it correctly based on fixture units and hydraulic load, and the local code requirements for toilet counts. The video also highlights the necessity of installing cleanouts for sewer line access and using expansion joints to accommodate pipe movement due to temperature changes and building material shrinkage, ensuring a leak-free system.

Takeaways

• 🏠 The video discusses a specific aspect of a recently completed spec house, focusing on the plumbing system.
• 🌟 A 'plumbing stack', also known as a 'soil or waste stack', is a vertical pipe that passes through one or more stories and includes any offsets that are part of the stack.
• 💧 The stack's purpose is to carry wastewater and sewage to the underground drainage pipes.
• 📏 The term 'stack' originates from the concept of a vertical column of straight pipe that extends from floor to ceiling.
• 🔗 The video mentions a 'vent stack', which is a pipe that connects to the top of a stack to outside air.
• 🏡 A single house can have multiple stacks depending on the architectural layout and the hydraulic load imposed by plumbing fixtures.
• 📚 'Hydraulic load' is represented by a factor called 'fixture units', which are units of measure based on the rate of discharge and frequency of discharge of the fixture.
• 📏 Local code books should be consulted to determine the fixture units each fixture imposes and to correctly size drain pipes.
• 🚿 The video highlights a trick for drilling a hole at a 45-degree angle for an offset in the plumbing system.
• 📏 For stacks serving more than six toilets, local codes may require a minimum size of four inches, regardless of the hydraulic load.
• 🔧 Every stack must have a 'clean out', which provides access to the sewer lines, and should be installed not more than three meters upstream from the bottom of the stack.
• 🔄 An 'expansion joint' is necessary to allow for expansion and contraction of the pipe due to temperature changes and shrinkage of building materials.

Q & A

What is the main focus of the video?

The main focus of the video is connecting all the top floor bathrooms to the main plumbing stack.

What is a plumbing stack, also known as a soil or waste stack?

A plumbing stack, also known as a soil or waste stack, is a vertical pipe that passes through one or more stories and includes any offset that is part of the stack. It carries wastewater and sewage to the underground drainage pipes.

What does the term 'stack' signify in plumbing?

The term 'stack' signifies a vertical column of straight pipe that extends from floor to ceiling in a building's plumbing system.

What is the purpose of a vent in relation to a plumbing stack?

A vent is a pipe that connects to the top of a stack to allow outside air to enter the plumbing system, which helps to maintain proper pressure and prevent sewer gases from entering the building.

How does the architectural layout of a house affect the number of stacks it has?

The architectural layout of a house, along with the hydraulic load imposed by plumbing fixtures, determines whether a house has one or multiple stacks.

What is hydraulic load in the context of plumbing?

Hydraulic load refers to the demand placed on a plumbing system by the fixtures within it, represented by a factor called fixture units, which are based on the rate, time, and frequency of discharge of the fixtures.

Why is it important to correctly size drain pipes according to fixture units?

Correctly sizing drain pipes according to fixture units ensures that the plumbing system can handle the flow and pressure from the fixtures, preventing blockages and potential damage.

What is the minimum size for a soil or waste stack serving more than six toilets according to the local codes mentioned in the video?

According to the local codes mentioned, any soil or waste stack serving more than six toilets cannot be less than four inches in diameter.

What is a cleanout and why is it necessary on a stack?

A cleanout is an access point on a stack that allows for maintenance and inspection of the sewer lines. It is necessary to facilitate easy cleaning and prevent blockages in the plumbing system.

Where should a cleanout be installed on a stack?

A cleanout should be installed on the stack not more than three meters upstream from the bottom of the stack or on a Y-fitting that connects the stack to the building drain or branch drain.

Why is it important to use an expansion joint in a plumbing stack?

An expansion joint is used to allow for expansion and contraction of the pipe due to temperature changes and shrinkage of building materials, preventing stress on the pipe and potential leaks.

What should be avoided when installing a plumbing stack to prevent future leaks?

One should avoid bending or pulling the pipe into position after it has been glued, as this can compromise the joint and lead to future leaks, especially after the drywall is completed.