Vents

Air Admittance Valves Are Allowed Only Where Approved and Accessible

Are air admittance valves allowed under IRC?

P3114.1

At Least One Plumbing Vent Must Terminate Outdoors

Does a house need a plumbing vent through the roof?

P3102.1

Bathroom Groups Can Use Horizontal Wet Venting Under IRC Limits

What is a horizontal wet vent in a bathroom?

P3108.1

Every Trapped Fixture Needs Trap Seal Protection by Venting

Does every plumbing fixture need a vent?

P3101.2

Fixture Vents Must Connect Within the Allowed Trap Arm Distance

How far can a trap be from its vent?

P3105.1

Island Fixture Vents Need a Code-Compliant Loop or Approved Alternative

What is the code way to vent an island sink?

P3112.1

Plumbing Vents Must Be Kept Away From Openings and Air Intakes

How far must a plumbing vent be from a window or door?

P3103.5

Roof Vent Terminations Need Required Height and Weather Protection

How high does a plumbing vent need to be above the roof?

P3103.1

Two Fixtures Can Share a Common Vent Only in Specific Layouts

Can two sinks share one vent?

P3107.1

Vent Piping Must Drain Condensate Back to the Drainage System

Does plumbing vent pipe need slope?

P3104.2