How To Look At A House

McGarry and Madsen's home inspection blog for buyers of  

site-built, mobile/manufactured and modular homes

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

Saturday, October 6, 2018

Your sky-high water bill could be due to either a temporary jump in water usage or a leak. To find out if it’s a leak, first shut off all your water-using fixtures in the house, including the automatic ice maker.  Take the cover off your water meter box (typically somewhere along the front property line, often near a corner) and flip open the protective cover plate on the meter dial. You may have to dig down a little in the dirt to find it.

   If you’re lucky, the meter is a newer one, and has a small triangular or diamond-shaped low-flow indicator near the center, usually red--like in the photo above. It should not be turning. But if it is, there’s a leak somewhere in your plumbing system. At a meter without a low-flow indicator, note the meter reading and check back in an hour of so and see if it has changed. 

   Here’s a few places to check if the meter says you have water flow:

•• Faucets - Not just at the sinks. Also check the faucets at the washing machine hookup, water heater, tub/shower, and the outside hose faucets.

•• Toilet Tanks - A bad flapper valve that doesn’t seat properly at the bottom of the tank will cause a leak, along with a bad ballcock arm or a defective overflow tube. Drop a dye tablet (available in most hardware stores specifically for toilet testing) in the tank. Do not flush, and wait 15-minutes. If the color shows up in the bowl, the toilet needs repair.

•• TPR Valve at Water Heater - The small valve with a flip-up handle at the top or side of the water heater, called a Temperature and Pressure Release valve, is designed to open if the water gets too hot, to keep the tank from exploding. These valves sometimes fail by opening slightly and letting loose a slow trickle of hot water, which runs in a pipe to a discrete location near the ground at the exterior wall. Find the termination of the TPR valve and check for a drip. 

•• Under the Floor Slab - These are the hardest to detect until they get really bad. Walk around the perimeter of the home and look for any muddy areas at the base of the walls, and especially any areas where the soil has washed away a little under the slab, creating a pocket. Wet spots in the floor and moist, discolored baseboards are another clue.

•• Between the Water Meter and the House - Again, leaks here are difficult to detect until they become gushers and water starts bubbling up out of the ground. But some homes have a secondary water shut-off valve in the ground, usually near the front wall of the house. If your house has one (and it’s still functional, because they freeze up with age), try shutting the water off there. If the meter continues to show water flow then your problem, or at least part of it, is underground in the yard. 

   Two types of water supply piping tend to fail prematurely: galvanized steel and PB (polybutylene). Also, copper pipe can deteriorate early when the water is especially acidic--but that is a rare problem in the Gainesville area. So also take into consideration the type of piping you have. And, when all else fails, call a good plumber. 

    Also, see our blog post How do you accurately find a broken water pipe leak under the floor slab?

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

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

Can galvanized steel pipe still be used for new water lines in a house? 

How can I tell if I have cast iron pipes in my house? 

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

What is the difference between green and white sewer drain pipes?

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

What are the abandoned pipes sticking out of the wall in my house?  

What are the code requirements for plumbing vent terminations?

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

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

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

What is a building trap?  

What is a galvanized nipple?

What are the pipes sticking out near my water valves?

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

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

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

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

What is a dielectric union? 

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

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

What are the pipes on my roof? 

• How can I find out what type of water pipe runs underground from the water meter to the house (service pipe)?

What is a P-trap?

Why is old galvanized steel water pipe a problem for homebuyers?

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

• Which water pipes are an insurance problem and possibly uninsurable?

• Can you connect CPVC pipe directly to a gas water heater?  

     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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