How does a home inspector check a toilet?

Saturday, October 6, 2018

Both the tank and bowl of the toilet must be filled with water before a toilet can be tested. When the lever on the tank is pressed, it flips up a rubber stopper called a flapper, which releases the water in the tank to flow into the bowl. The water flushing action is accomplished by water shooting from small holes around the inner ring of the top of the bowl, in coordination with a siphoned jet hole at the bottom of the bowl. The bowl should be rinsed clean at the end of the flush, as the flapper resets itself over the opening at the bottom of the tank and the tank refills.

   Here’s what we check:

•• The tank and bowl should have a smooth, cleanable surface without any cracks.

•• The inspector will straddle the toilet bowl between his legs with a gentle rocking action to see if the connection to the floor is loose. A secure, bolted connection to floor is important: a loose bowl will eventually open the wax seal connection to the drain pipe in the floor, and allow slow leakage to spread across the floor. When the toilet is sitting on a wood floor structure, wood rot will weaken the floor over time. Also, he will confirm with a nudge that the connection between the tank and the bowl is not loose.

•• When flushed, the bowl should drain promptly and completely, and the tank should refill in a reasonable amount of time. We note if the toilet fill valve opens intermittently due to a small leak or runs continuously. If uncertain about a leak, we put a small dye tablet in the tank and wait a couple of minutes. Any dye color that shows up in the bowl indicates a problem. An infrared camera or moisture meter may also be used if we suspect moisture around the base of the toilet.

•• The interior of tank should be examined for mold, sand accumulation, cracks in porcelain, and damage to flush mechanism.

    The standard residential toilet is a called a gravity type. More sophisticated designs include the vacuum-assist and pressure-assist toilets, both of which have an enhanced--but noisier--flush. 

   A federal mandate in 1994 requires new toilets to have a maximum 1.6 gallon flush volume, but one variation on the standard toilet is a dual-flush, with a choice of two buttons for either a low-volume (1.0 gallons, for liquid only) or regular (1.6 gallons, for solid waste) flush. 

  Everyone in the building trades has a favorite toilet story. Ours is about an old-time builder we know who would push the merits of buying one of his brand-new homes versus an older one by saying: “You know, you shouldn’t have to sit on another man’s toilet!”

    Also, see our blog posts Why is there mold inside my toilet tank? and What are the pros and cons of a wall-mounted toilet? and Why is there sand in the bottom of my toilet tank? and Honey, who shrunk the toilet?


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Here’s links to a collection of our other blog posts about PLUMBING:

How can I protect my pipes to keep them from bursting during a hard winter freeze in North Florida?

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

Are drop-in toilet bowl cleaner tablets safe? 

What can I add to my septic tank to help it work better?

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

Why is there mold inside my toilet tank?  

What are the pros and cons of a wall-mounted toilet?

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

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

Are plastic pipes (PVC, CPVC, and PEX) safe for drinking water? 

Why is a backflow preventer required on lawn sprinkler systems? 

How can I locate my septic tank? 

Is a hot water faucet handle required to be on the left? 

Can you live in a house while the plumbing is being replaced? 

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

Why can't PVC be used for water pipe inside a house? 

What are the common problems to look for when the plumbing has been replaced in a house? 

What's that powdery crust on the pipe connections at the water heater? 

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

  What causes low water pressure in a house?

Should I call a plumber or septic tank contractor when my septic tank backs up into the house? 

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

What are the pipes on my roof? 

Should I wrap the water heater with an insulation blanket? 

My water bill went way up last month. How do I look for a leak?

Why does the water have a rotten-egg smell in some empty houses? 

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

Where is the septic tank? Are you going to inspect it? 

What does polybutylene pipe look like? Why is it a problem?

Which water pipes are an insurance problem and possibly uninsurable? 

• Does a home inspector check the plumbing under the floor slab?

• Is it alright to disconnect the washing machine drain from the septic tank and divert it to the ground in the yard?

      Visit our PLUMBING page for other related blog posts on this subject, or go to the INDEX for a complete listing of all our articles.  

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