How To Look At A House

McGarry and Madsen's home inspection blog for buyers of  

site-built, mobile/manfuactured and modular homes


Friday, April 10, 2020

Here’s links to a collection of our blog posts about PLUMBING DRAINS AND TRAPS:

• Why can't a sanitary tee be used for a horizontal-to-horizontal drain pipe connection? 

• Is a washing machine drain hose required to be secured at the standpipe?

 • Why is it a problem when a trap under a sink is installed backwards? 

• What are the code requirements for plumbing vent terminations?

• What are the code requirements for layout of drain piping under sinks?

• What are the building code requirements for gray water reuse in Florida?

• What causes a gurgling sound when a bathtub or sink drains? 

 What is the difference between a vent stack and a stack vent?

• What is a "combination waste and vent" in a plumbing system? 

• Why is garbage disposal not allowed at a combination waste and vent (CW&V) under a sink?

• What is a building trap?  

• What is an indirect waste receptor? 

• What is the difference between water pipe and sewage (waste) pipe? 

• How can I tell if a house is connected to a septic tank system or sewer?

• What type of water supply and drain (DWV) pipes were commonly used in the 2000s? 

• What type water supply and drain (DWV) pipes were commonly used for 1990s residential plumbing?

What type water supply and drain (DWV) pipes were commonly used for 1980s residential plumbing?

• What type water supply and drain (DWV) pipes were commonly used for 1970s residential plumbing?  

• What type water supply and drain (DWV) pipes were commonly used for 1960s residential plumbing? 

• What type water supply and drain (DWV) pipes were commonly used for 1950s residential plumbing?

Should I seal the washing machine drain hose to the standpipe?

 • Why is the European-style bottle trap not approved by the plumbing codes in the U.S.? 

• What is an auto vent, air admittance valve, or check vent?

• Can I make a trap under the sink from straight pipe and 90º elbows?  

• If all the plumbing drains have water in them and you can still smell sewer gas, what's causing the problem?  

• Why is there a flexible accordion pipe under the sink? 

• How do I get rid of the sewer gas smell in my house?  

• What are the pipes on my roof? 

• What is a "cross connection" in a home's plumbing system?

• What is an "S-Trap" under my sink? Why is it a problem? 

• What is a P-trap?

• What is the difference between gray water and black water in the plumbing code? 

Is a sink required to have a drain stopper? 

• Can a laundry sink drain be installed without a trap under it? 

• What is a drum trap at a plumbing drain?

• Can a dishwasher drain hose be connected after the sink trap (to the trap arm)? 

How far away from the sink can I install a dishwasher? 

What is a "high drain loop" or "air gap" in a dishwasher drain hose?

• What is the minimum and maximum distance a P-trap can be below a sink? 

• Is an air admittance valve (AAV) legal by code? 

• What is a double trap in plumbing? 

• Can two sinks share a trap? 

• Does a home inspector check sewer lines underground? 

• What types of plumbing traps are illegal by code? 

What is bell trap at a plumbing drain? 

• How many plumbing vents through the roof are required by code? 

• Why is there a floor drain in the laundry room? 

• Can an air conditioning condensate drain pipe connect to a sink drain? 

What is the minimum and maximum slope of the trap arm of a plumbing drain? 

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