ProVent-IPC-Comparison-Manual-Booklet-03.22.17 - Comparison of ProVent Design Rules and The International Plumbing Code - Guide to Contents

Oct 25, 2026

Uploaded by Rowan

Comparison guide contrasting ProVent Systems plumbing design rules with the International Plumbing Code for single stack waste and vent configurations. It explains how ProVent StackVent and BaseVent components control wastewater flow velocity using internal baffles, offsets, and separation shields, and contrasts uncontrolled conventional stack behavior that leads to air closure, siphonage, and backpressure. Includes chart-based maximum loading by stack size and sections describing stack vent separations, fixture unit capacity differences, and applications such as base connections and back-to-back bathroom layouts.

LanguageEnglish

CategoryTechnology

FormatPDF

Pages12

Reading Time30 min

AccessFree to download

Guide to Contents

Interior views of stack and base fittings

StackVent: controlled flow velocity and air mix

Maximum loading by stack size (Chart 3)

IPC Waste StackVent and combination drain/vent rules

ProVent base fittings and branch connection applications

ProVent Systems® Plumbing Fundamentals Educational Literature Comparison of ProVent® Design Rules and The International Plumbing Code Guide to Contents | Topics and Descriptions | Page | | --- | --- | | | | | Interior views of the Stack and Base fittings. | 3 | | Shows the baffles and offsets inside fittings that controls the velocity flows of wastewater inside the fittings. | | | Stack Vent Separations of water and air. | 4 | | Shows what the interior waste water and air flows look like when operating at maximum fixture unit chart ratings. | | | Comparing known single stack waste and vent systems. | 5 | | Shows the difference between the single stack method using ProVent fittings with the allowable amount of fixture units compared with the limited fixture units of the IPC single stack method. Notice the big difference between the 4" and the 5" IPC chart. | | | Conventional waste stack flow velocities. | 6 | | Shows how waste water velocities build up inside conventional stacks without ProVent stack fittings. | | | ProVent base fitting connecting horizontal drains. | 7 | | Shows where fixture openings can be connected at the base of a stack using ProVent and the reasons it can be different from IPC connections. | | | Interior look at the Base fitting and the Pressure Relief Vent. | 8 | | Shows the hydraulic jump at the base of the stack and shows how the Base fitting lowers the jump and vents the horizontal line. | | | Water flows in designed horizontal branch piping. | 9 | | Shows the interior flow rates of both the ProVent and the conventional IPC method. | | | Lavatory and Sink connections. | 10 | | Shows the ProVent method of connecting this type of fixture without additional venting and the same type of allowance shown in the IPC code. | | | Impact of ProVent System on Plumbing Design and Cost for
Back-to-Back Bathrooms | 11 | | Shows the difference between ProVent and conventional plumbing designs for a back-to-back bathroom layout | | Copyright􀂤 2007-2008 ProVent Systems. Inc Page 2 Interior View of the ProVent Fittings Shows How Fittings Control Flow Velocity in the Stack StackVent BaseVent Stack Inlet Velocity Offset Branch Vent Branch Baffle Separation Shield Velocity Offset Collection Chamber Stack Outlet Inlet Relief Vent (Controls Back Pressure) Nose Baffle (Controls Velocity) Outlet Copyright􀂤 2007-2008 ProVent Systems. Inc Page 3 Uncontrolled Flow Velocity in Conventional Waste Stacks Velocity Close to Inlet Open Airway in center of pipe permits normal air flow (up to 20’ vertical drop) . Velocity Increases With Vertical Drop The increase in water flow velocity causes the thickness of water flow to build up. Reaches Terminal Velocity The air opening in the center of the pipe is completely closed, forming a water plug. This causes siphonage and backpressure unless the branches are separately vented -requiring a separate vent and revent. Waste Stack Copyright􀂤 2007-2008 ProVent Systems. Inc Page 4 Controlled Flow Velocity: ProVent StackVent StackVent Air The maximum flow of the branch drainage never exceeds quarter-full flow conditions at the inlet. The StackVent maintains the proper air mix. The stack length never exceeds 20 feet in length without either a StackVent or a velocity breaker offset (See Drawing 1.4 in ProVent Guide) . This rule is subject to compliance with the maximum loading by stack as outlined in Chart 3 of the ProVent Guide (shown below) | CHART 3: MAXIMUM LOADING BY STACK | | | --- | --- | | Stack Size | Fixture Units | | 3” | 64 | | 3”(over 7 stories) | 102 | | 4” | 504 | | 5” | 1,010 | | 6” | 2,200 | StackVent A StackVent is required at every floor when connecting branch piping is 2 1/2” or larger in diameter (See Drawing 1.4 in ProVent Guide) Copyright􀂤 2007-2008 ProVent Systems. Inc Page 5 ProVent PVC StackVent Fitting A StackVent fitting creates a combination drain and vent for

FAQs

How does ProVent StackVent control wastewater flow velocity in a stack?

ProVent fittings use internal baffles and offsets to maintain controlled, quarter-full inlet conditions for branch drainage and preserve proper air mixing. This reduces velocity buildup compared with conventional stacks.

What is the key difference between conventional waste stacks and ProVent-controlled stacks?

Conventional stacks can experience increasing velocity with vertical drop, eventually forming a water plug when central air openings close, causing siphonage and backpressure unless branches are separately vented. ProVent design prevents this by controlling flow velocity and air separation.

How do ProVent and IPC combination drain-and-vent systems compare in capacity?

The guide shows a dramatic increase in allowable fixture unit loading for the ProVent system due to controlled flow velocity. It also highlights capacity limits in the IPC approach, especially the large difference between 4" and larger stack sizes.

Oct 25, 2026

Uploaded by Rowan