1933 World’s Fair Poster - Wikipedia Commons


More Blogs on Similar Subjects:

  1. So the water heater is older...what’s the big deal?

  2. Should I upgrade to a tankless water heater?

  3. How old is that water heater?

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

  5. Should I wrap the water heater with an insulation blanket?

  6. Do you check the plumbing under the floor slab?

  7. This home has galvanized water pipe. Is that a problem?

  8. How much does it cost to replace the plumbing pipe in a house?

  9. What causes low water pressure in a house?

  10. What is the difference between water service pipe and water supply pipe?

  11. Are there water lines in my attic or under the floor slab?

  12. What’s the flip-up handle on the water heater for?

  13. What are the pipes on my roof?

  14. How can I tell what type of plumbing pipe I have?

  15. How come the water has a rotten-egg smell in some empty houses?

  16. What is the difference between a regular water heater and a power vent water heater?

  17. What is a grinder pump?

  18. What is that little tank on top of the water heater for?

  19. What are the most common plumbing problems with older houses?

  20. What is a dielectric union?

  21. What is a heat pump water heater?

  22. What is the average life expectancy of copper pipe?

  23. What is the average life expectancy of PVC pipe?

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

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

  26. What is an escutcheon plate?

  27. Why is sunlight exposure bad for PVC pipe?

  28. What are the right words for talking about a house plumbing system?

  29. How can I tell if a house is connected to a septic tank or sewer?

  30. How do you find a broken water pipe leak under the floor slab?

  31. What is a sediment trap or dirt leg?

  32. My spa tub stopped working. What’s wrong?

  33. Which plumbing fixtures require water shut off valves in a home?

How to Look

at a House


A blog with answers
to your questions about
HOME INSPECTION
and HOME MAINTENANCE

Search This Blog

Click Below to Link
to Collections of
Blog Posts by Subject

Welcome to our blog!
We want you to be an informed homebuyer, and each blog post is a question that we have answered for our friends and customers over the years. Hope they help you make a good choice for your next home.

   A typical example in a Gainesville home of a situation that could cause a cross connection would be an exterior hose faucet without a “vacuum breaker” installed. If the homeowner is adding water to a backyard pool or pond with a hose inserted into the water, and
pump serving the municipal water system fails,
the lack of water pressure can cause the
contents of the pond or pool to be sucked up
into the home’s water supply piping. An even
worse  contamination would be created if the
hose was connected to a spray-jar containing
insecticide or liquid fertilizer--which is why
vacuum breakers (the round brass attachment
screwed onto the end of a hose faucet, as in
the diagram at right) have been required by the
building code for a number of years now.

   Another cross contamination scenario would
be created by a sink with a faucet arm that
extends below the rim of the sink. If the sink is full to the rim and the water pressure fails, siphoning of the sink contents into the water supply will begin. The modern plumbing code addresses this possibility by requiring faucet arms to terminate safely above the rim of the sink, creating what is called in the plumbing trade an “air gap.”

   Professional plumbers are always on the lookout for piping/fixture configurations that might cause cross contamination. And so are we.


While we hope you find this series of articles about home inspection helpful, they should not be considered an alternative to an actual home inspection by a local inspector. Also, construction standards vary in different parts of the country and it is possible that important issues related to your area may not be covered here.
©2015 - McGarry and Madsen Inspection.